ts-canvasrenderingcontext2d.md 94.2 KB
Newer Older
Z
zengyawen 已提交
1 2
# CanvasRenderingContext2D

E
ester.zhou 已提交
3
Use **RenderingContext** to draw rectangles, text, images, and other objects on a canvas.
Z
zengyawen 已提交
4

E
ester.zhou 已提交
5 6
> **NOTE**
>
E
ester.zhou 已提交
7
> The APIs of this module are supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.
Z
zengyawen 已提交
8

E
esterzhou 已提交
9 10


Z
zengyawen 已提交
11 12 13 14
## APIs

CanvasRenderingContext2D(setting: RenderingContextSetting)

E
ester.zhou 已提交
15 16
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
17 18 19 20 21
**Parameters**

| Name    | Type                                    | Mandatory  | Description                                    |
| ------- | ---------------------------------------- | ---- | ---------------------------------------- |
| setting | [RenderingContextSettings](#renderingcontextsettings) | Yes   | See [RenderingContextSettings](#renderingcontextsettings).|
Z
zengyawen 已提交
22 23 24 25


### RenderingContextSettings

26
RenderingContextSettings(antialias?: boolean)
Z
zengyawen 已提交
27 28 29

Configures the settings of a **CanvasRenderingContext2D** object, including whether to enable antialiasing.

E
ester.zhou 已提交
30 31
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
32 33 34 35
**Parameters**

| Name      | Type   | Mandatory  | Description                         |
| --------- | ------- | ---- | ----------------------------- |
E
ester.zhou 已提交
36
| antialias | boolean | No   | Whether to enable antialiasing.<br>Default value: **false**|
Z
zengyawen 已提交
37 38 39 40


## Attributes

E
ester.zhou 已提交
41 42
| Name                                                 | Type                                                        | Description                                                        |
| ----------------------------------------------------- | ------------------------------------------------------------ | ------------------------------------------------------------ |
E
ester.zhou 已提交
43
| [fillStyle](#fillstyle)                               | string \|number<sup>10+</sup> \|[CanvasGradient](ts-components-canvas-canvasgradient.md) \| [CanvasPattern](#canvaspattern) | Style to fill an area.<br>- When the type is string, this attribute indicates the color of the fill area.<br>- When the type is number, this attribute indicates the color of the fill area.<br>- When the type is **CanvasGradient**, this attribute indicates a gradient object, which is created using the **[createLinearGradient](#createlineargradient)** API.<br>- When the type is **CanvasPattern**, this attribute indicates a pattern, which is created using the **[createPattern](#createpattern)** API.<br>Since API version 9, this API is supported in ArkTS widgets.|
E
ester.zhou 已提交
44
| [lineWidth](#linewidth)                               | number                                                       | Line width.                                        |
E
ester.zhou 已提交
45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
| [strokeStyle](#strokestyle)                           | string \|number<sup>10+</sup> \|[CanvasGradient](ts-components-canvas-canvasgradient.md) \| [CanvasPattern](#canvaspattern) | Stroke style.<br>- When the type is string, this attribute indicates the stroke color.<br>- When the type is number, this attribute indicates the stroke color.<br>- When the type is **CanvasGradient**, this attribute indicates a gradient object, which is created using the **[createLinearGradient](#createlineargradient)** API.<br>- When the type is **CanvasPattern**, this attribute indicates a pattern, which is created using the **[createPattern](#createpattern)** API.<br>Since API version 9, this API is supported in ArkTS widgets.|
| [lineCap](#linecap)                                   | CanvasLineCap                                                | Style of the line endpoints. The options are as follows:<br>- **'butt'**: The endpoints of the line are squared off.<br>- **'round'**: The endpoints of the line are rounded.<br>- **'square'**: The endpoints of the line are squared off by adding a box with an equal width and half the height of the line's thickness.<br>Default value: **'butt'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [lineJoin](#linejoin)                                 | CanvasLineJoin                                               | Style of the shape used to join line segments. The options are as follows:<br>- **'round'**: The shape used to join line segments is a sector, whose radius at the rounded corner is equal to the line width.<br>- **'bevel'**: The shape used to join line segments is a triangle. The rectangular corner of each line is independent.<br>- **'miter'**: The shape used to join line segments has a mitered corner by extending the outside edges of the lines until they meet. You can view the effect of this attribute in **miterLimit**.<br>Default value: **'miter'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [miterLimit](#miterlimit)                             | number                                                       | Maximum miter length. The miter length is the distance between the inner corner and the outer corner where two lines meet.<br>Default value: **10**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [font](#font)                                         | string                                                       | Font style.<br>Syntax: ctx.font='font-size font-family'<br>- (Optional) **font-size**: font size and row height. The unit can only be pixels.<br>- (Optional) **font-family**: font family.<br>Syntax: ctx.font='font-style font-weight font-size font-family'<br>- (Optional) **font-style**: font style. Available values are **'normal'** and **'italic'**.<br>- (Optional) **font-weight**: font weight. Available values are as follows: **'normal'**, **'bold'**, **'bolder'**, **'lighter'**, **'100'**, **'200'**, **'300'**, **'400'**, **'500'**, **'600'**, **'700'**, **'800'**, **'900'**.<br>- (Optional) **font-size**: font size and row height. The unit can only be pixels.<br>- (Optional) **font-family**: font family. Available values are **'sans-serif'**, **'serif'**, and **'monospace'**.<br>Default value: **'normal normal 14px sans-serif'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [textAlign](#textalign)                               | CanvasTextAlign                                              | Text alignment mode. Available values are as follows:<br>- **'left'**: The text is left-aligned.<br>- **'right'**: The text is right-aligned.<br>- **'center'**: The text is center-aligned.<br>- **'start'**: The text is aligned with the start bound.<br>- **'end'**: The text is aligned with the end bound.<br>In the **ltr** layout mode, the value **'start'** equals **'left'**. In the **rtl** layout mode, the value **'start'** equals **'right'**.<br>Default value: **'left'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [textBaseline](#textbaseline)                         | CanvasTextBaseline                                           | Horizontal alignment mode of text. Available values are as follows:<br>- **'alphabetic'**: The text baseline is the normal alphabetic baseline.<br>- **'top'**: The text baseline is on the top of the text bounding box.<br>- **'hanging'**: The text baseline is a hanging baseline over the text.<br>- **'middle'**: The text baseline is in the middle of the text bounding box.<br>**'ideographic'**: The text baseline is the ideographic baseline. If a character exceeds the alphabetic baseline, the ideographic baseline is located at the bottom of the excess character.<br>- **'bottom'**: The text baseline is at the bottom of the text bounding box. Its difference from the ideographic baseline is that the ideographic baseline does not consider letters in the next line.<br>Default value: **'alphabetic'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [globalAlpha](#globalalpha)                           | number                                                       | Opacity.<br>**0.0**: completely transparent.<br>**1.0**: completely opaque.<br>Since API version 9, this API is supported in ArkTS widgets.|
| [lineDashOffset](#linedashoffset)                     | number                                                       | Offset of the dashed line. The precision is float.<br>Default value: **0.0**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [globalCompositeOperation](#globalcompositeoperation) | string                                                       | Composition operation type. Available values are as follows: **'source-over'**, **'source-atop'**, **'source-in'**, **'source-out'**, **'destination-over'**, **'destination-atop'**, **'destination-in'**, **'destination-out'**, **'lighter'**, **'copy'**, and **'xor'**.<br>Default value: **'source-over'**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [shadowBlur](#shadowblur)                             | number                                                       | Blur level during shadow drawing. A larger value indicates a more blurred effect. The precision is float.<br>Default value: **0.0**<br>Since API version 9, this API is supported in ArkTS widgets.|
| [shadowColor](#shadowcolor)                           | string                                                       | Shadow color.<br>Since API version 9, this API is supported in ArkTS widgets.|
| [shadowOffsetX](#shadowoffsetx)                       | number                                                       | X-axis shadow offset relative to the original object.<br>Since API version 9, this API is supported in ArkTS widgets.|
| [shadowOffsetY](#shadowoffsety)                       | number                                                       | Y-axis shadow offset relative to the original object.<br>Since API version 9, this API is supported in ArkTS widgets.|
| [imageSmoothingEnabled](#imagesmoothingenabled)       | boolean                                                      | Whether to adjust the image smoothness during image drawing. The value **true** means to enable this feature, and **false** means the opposite.<br>Default value: **true**<br>Since API version 9, this API is supported in ArkTS widgets.|
E
ester.zhou 已提交
60 61 62 63

> **NOTE**
>
> The string-type value of **fillStyle**, **shadowColor**, and **strokeStyle** can be in 'rgb(255, 255, 255)', 'rgba(255, 255, 255, 1.0)', or '\#FFFFFF' format.
Z
zengyawen 已提交
64 65 66 67


### fillStyle

68 69
```ts
// xxx.ets
Z
zengyawen 已提交
70 71 72
@Entry
@Component
struct FillStyleExample {
E
ester.zhou 已提交
73 74
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
75 76 77 78 79 80 81 82 83

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.fillStyle = '#0000ff'
E
ester.zhou 已提交
84
          this.context.fillRect(20, 20, 150, 100)
Z
zengyawen 已提交
85 86 87 88 89 90 91 92
        })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
93 94 95 96
![en-us_image_0000001257058395](figures/en-us_image_0000001257058395.png)


### lineWidth
Z
zengyawen 已提交
97

98 99
```ts
// xxx.ets
Z
zengyawen 已提交
100 101 102
@Entry
@Component
struct LineWidthExample {
E
ester.zhou 已提交
103 104
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
        this.context.lineWidth = 5
        this.context.strokeRect(25, 25, 85, 105)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
123 124 125 126
![en-us_image_0000001212378408](figures/en-us_image_0000001212378408.png)


### strokeStyle
Z
zengyawen 已提交
127

128 129
```ts
// xxx.ets
Z
zengyawen 已提交
130 131 132
@Entry
@Component
struct StrokeStyleExample {
E
ester.zhou 已提交
133 134
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.lineWidth = 10
          this.context.strokeStyle = '#0000ff'
          this.context.strokeRect(25, 25, 155, 105)
        })
    }
    .width('100%')
    .height('100%')
  }
}
```


Z
zengyawen 已提交
155 156 157 158 159
![en-us_image_0000001212218446](figures/en-us_image_0000001212218446.png)


### lineCap

160 161
```ts
// xxx.ets
Z
zengyawen 已提交
162 163 164
@Entry
@Component
struct LineCapExample {
E
ester.zhou 已提交
165 166
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.lineWidth = 8
          this.context.beginPath()
          this.context.lineCap = 'round'
          this.context.moveTo(30, 50)
          this.context.lineTo(220, 50)
          this.context.stroke()
        })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
189 190 191 192
![en-us_image_0000001212378406](figures/en-us_image_0000001212378406.png)


### lineJoin
Z
zengyawen 已提交
193

194 195
```ts
// xxx.ets
Z
zengyawen 已提交
196 197 198
@Entry
@Component
struct LineJoinExample {
E
ester.zhou 已提交
199 200
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
        this.context.beginPath()
        this.context.lineWidth = 8
        this.context.lineJoin = 'miter'
        this.context.moveTo(30, 30)
        this.context.lineTo(120, 60)
        this.context.lineTo(30, 110)
        this.context.stroke()
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
224 225 226 227
![en-us_image_0000001212218438](figures/en-us_image_0000001212218438.png)


### miterLimit
Z
zengyawen 已提交
228

229 230
```ts
// xxx.ets
Z
zengyawen 已提交
231 232 233
@Entry
@Component
struct MiterLimit {
E
ester.zhou 已提交
234 235
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.lineWidth = 8
          this.context.lineJoin = 'miter'
          this.context.miterLimit = 3
          this.context.moveTo(30, 30)
          this.context.lineTo(60, 35)
          this.context.lineTo(30, 37)
          this.context.stroke()
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
259 260 261 262
![en-us_image_0000001212378398](figures/en-us_image_0000001212378398.png)


### font
Z
zengyawen 已提交
263

264 265
```ts
// xxx.ets
Z
zengyawen 已提交
266 267
@Entry
@Component
E
ester.zhou 已提交
268
struct Fonts {
E
ester.zhou 已提交
269 270
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.font = '30px sans-serif'
          this.context.fillText("Hello World", 20, 60)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
289 290 291 292
![en-us_image_0000001257058409](figures/en-us_image_0000001257058409.png)


### textAlign
Z
zengyawen 已提交
293

294 295
```ts
// xxx.ets
Z
zengyawen 已提交
296 297
@Entry
@Component
E
ester.zhou 已提交
298
struct CanvasExample {
E
ester.zhou 已提交
299 300
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
        this.context.strokeStyle = '#0000ff'
        this.context.moveTo(140, 10)
        this.context.lineTo(140, 160)
        this.context.stroke()
        this.context.font = '18px sans-serif'
        this.context.textAlign = 'start'
        this.context.fillText('textAlign=start', 140, 60)
        this.context.textAlign = 'end'
        this.context.fillText('textAlign=end', 140, 80)
        this.context.textAlign = 'left'
        this.context.fillText('textAlign=left', 140, 100)
        this.context.textAlign = 'center'
        this.context.fillText('textAlign=center',140, 120)
        this.context.textAlign = 'right'
        this.context.fillText('textAlign=right',140, 140)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
332 333 334 335
![en-us_image_0000001256978351](figures/en-us_image_0000001256978351.png)


### textBaseline
Z
zengyawen 已提交
336

337 338
```ts
// xxx.ets
Z
zengyawen 已提交
339 340 341
@Entry
@Component
struct TextBaseline {
E
ester.zhou 已提交
342 343
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.strokeStyle = '#0000ff'
          this.context.moveTo(0, 120)
          this.context.lineTo(400, 120)
          this.context.stroke()
          this.context.font = '20px sans-serif'
          this.context.textBaseline = 'top'
          this.context.fillText('Top', 10, 120)
          this.context.textBaseline = 'bottom'
          this.context.fillText('Bottom', 55, 120)
          this.context.textBaseline = 'middle'
          this.context.fillText('Middle', 125, 120)
          this.context.textBaseline = 'alphabetic'
          this.context.fillText('Alphabetic', 195, 120)
          this.context.textBaseline = 'hanging'
          this.context.fillText('Hanging', 295, 120)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
375 376 377 378
![en-us_image_0000001212058462](figures/en-us_image_0000001212058462.png)


### globalAlpha
Z
zengyawen 已提交
379

380 381
```ts
// xxx.ets
Z
zengyawen 已提交
382 383 384
@Entry
@Component
struct GlobalAlpha {
E
ester.zhou 已提交
385 386
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
387 388 389 390 391 392 393 394
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
E
ester.zhou 已提交
395 396 397 398 399
          this.context.fillStyle = 'rgb(0,0,255)'
          this.context.fillRect(0, 0, 50, 50)
          this.context.globalAlpha = 0.4
          this.context.fillStyle = 'rgb(0,0,255)'
          this.context.fillRect(50, 50, 50, 50)
Z
zengyawen 已提交
400 401 402 403 404 405 406 407
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

E
ester.zhou 已提交
408
![en-us_image_0000001194192434](figures/en-us_image_0000001194192434.png)
Z
zengyawen 已提交
409 410 411


### lineDashOffset
Z
zengyawen 已提交
412

413 414
```ts
// xxx.ets
Z
zengyawen 已提交
415 416 417
@Entry
@Component
struct LineDashOffset {
E
ester.zhou 已提交
418 419
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
420 421 422 423 424 425 426 427 428 429
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.arc(100, 75, 50, 0, 6.28)
          this.context.setLineDash([10,20])
E
ester.zhou 已提交
430 431
          this.context.lineDashOffset = 10.0
          this.context.stroke()
Z
zengyawen 已提交
432 433 434 435 436 437 438 439
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

E
ester.zhou 已提交
440
![en-us_image_0000001194352434](figures/en-us_image_0000001194352434.png)
Z
zengyawen 已提交
441 442 443 444


### globalCompositeOperation

E
ester.zhou 已提交
445 446 447 448 449 450 451 452 453 454 455 456 457
| Name              | Description                      |
| ---------------- | ------------------------ |
| source-over      | Displays the new drawing above the existing drawing. This attribute is used by default.  |
| source-atop      | Displays the new drawing on the top of the existing drawing.       |
| source-in        | Displays the new drawing inside the existing drawing.        |
| source-out       | Displays part of the new drawing that is outside of the existing drawing.       |
| destination-over | Displays the existing drawing above the new drawing.       |
| destination-atop | Displays the existing drawing on the top of the new drawing.       |
| destination-in   | Displays the existing drawing inside the new drawing.        |
| destination-out  | Displays the existing drawing outside the new drawing.        |
| lighter          | Displays both the new and existing drawing.         |
| copy             | Displays the new drawing and neglects the existing drawing.       |
| xor              | Combines the new drawing and existing drawing using the XOR operation.|
Z
zengyawen 已提交
458

459 460
```ts
// xxx.ets
Z
zengyawen 已提交
461 462 463
@Entry
@Component
struct GlobalCompositeOperation {
E
ester.zhou 已提交
464 465
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(20, 20, 50, 50)
          this.context.globalCompositeOperation = 'source-over'
          this.context.fillStyle = 'rgb(0,0,255)'
          this.context.fillRect(50, 50, 50, 50)
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(120, 20, 50, 50)
          this.context.globalCompositeOperation = 'destination-over'
          this.context.fillStyle = 'rgb(0,0,255)'
          this.context.fillRect(150, 50, 50, 50)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
492 493 494 495
![en-us_image_0000001211898480](figures/en-us_image_0000001211898480.png)


### shadowBlur
Z
zengyawen 已提交
496

497 498
```ts
// xxx.ets
Z
zengyawen 已提交
499 500 501
@Entry
@Component
struct ShadowBlur {
E
ester.zhou 已提交
502 503
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.shadowBlur = 30
          this.context.shadowColor = 'rgb(0,0,0)'
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(20, 20, 100, 80)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
524 525 526 527
![en-us_image_0000001256978343](figures/en-us_image_0000001256978343.png)


### shadowColor
Z
zengyawen 已提交
528

529 530
```ts
// xxx.ets
Z
zengyawen 已提交
531 532 533
@Entry
@Component
struct ShadowColor {
E
ester.zhou 已提交
534 535
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.shadowBlur = 30
          this.context.shadowColor = 'rgb(0,0,255)'
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(30, 30, 100, 100)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
556 557 558 559
![en-us_image_0000001257138353](figures/en-us_image_0000001257138353.png)


### shadowOffsetX
Z
zengyawen 已提交
560

561 562
```ts
// xxx.ets
Z
zengyawen 已提交
563 564 565
@Entry
@Component
struct ShadowOffsetX {
E
ester.zhou 已提交
566 567
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.shadowBlur = 10
          this.context.shadowOffsetX = 20
          this.context.shadowColor = 'rgb(0,0,0)'
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(20, 20, 100, 80)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
589 590 591 592
![en-us_image_0000001212218436](figures/en-us_image_0000001212218436.png)


### shadowOffsetY
Z
zengyawen 已提交
593

594 595
```ts
// xxx.ets
Z
zengyawen 已提交
596 597 598
@Entry
@Component
struct ShadowOffsetY {
E
ester.zhou 已提交
599 600
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.shadowBlur = 10
          this.context.shadowOffsetY = 20
          this.context.shadowColor = 'rgb(0,0,0)'
          this.context.fillStyle = 'rgb(255,0,0)'
          this.context.fillRect(30, 30, 100, 100)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
621 622 623 624
![en-us_image_0000001212378410](figures/en-us_image_0000001212378410.png)


### imageSmoothingEnabled
Z
zengyawen 已提交
625

626 627
```ts
// xxx.ets
Z
zengyawen 已提交
628 629 630
@Entry
@Component
struct ImageSmoothingEnabled {
E
ester.zhou 已提交
631 632 633
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
  private img:ImageBitmap = new ImageBitmap("common/images/icon.jpg")
Z
zengyawen 已提交
634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651
  
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
          this.context.imageSmoothingEnabled = false
          this.context.drawImage( this.img,0,0,400,200)
      })
    }
    .width('100%')
    .height('100%')
  }
}
```

Z
zengyawen 已提交
652
![en-us_image_0000001211898472](figures/en-us_image_0000001211898472.png)
Z
zengyawen 已提交
653 654


Z
zengyawen 已提交
655
## Methods
Z
zengyawen 已提交
656

Z
zengyawen 已提交
657 658 659 660

### fillRect

fillRect(x: number, y: number, w: number, h: number): void
Z
zengyawen 已提交
661 662 663

Fills a rectangle on the canvas.

E
ester.zhou 已提交
664 665
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
666 667 668 669 670 671 672 673
**Parameters**

| Name    | Type    | Mandatory  | Default Value | Description           |
| ------ | ------ | ---- | ---- | ------------- |
| x      | number | Yes   | 0    | X-coordinate of the upper left corner of the rectangle.|
| y      | number | Yes   | 0    | Y-coordinate of the upper left corner of the rectangle.|
| width  | number | Yes   | 0    | Width of the rectangle.     |
| height | number | Yes   | 0    | Height of the rectangle.     |
Z
zengyawen 已提交
674

E
ester.zhou 已提交
675
**Example**
H
HelloCrease 已提交
676

677 678
  ```ts
  // xxx.ets
Z
zengyawen 已提交
679 680 681
  @Entry
  @Component
  struct FillRect {
E
ester.zhou 已提交
682 683
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
684 685 686 687 688 689 690 691
    
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
692
            this.context.fillRect(30,30,100,100)
Z
zengyawen 已提交
693
         })
Z
zengyawen 已提交
694
        }
Z
zengyawen 已提交
695 696 697 698 699 700 701 702 703 704 705 706 707 708 709
      .width('100%')
      .height('100%')
    }
  }
  ```

  ![en-us_image_0000001212218440](figures/en-us_image_0000001212218440.png)


### strokeRect

strokeRect(x: number, y: number, w: number, h: number): void

Draws an outlined rectangle on the canvas.

E
ester.zhou 已提交
710 711
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
712 713 714 715 716 717 718 719
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description          |
| ---- | ------ | ---- | ---- | ------------ |
| x    | number | Yes   | 0    | X-coordinate of the upper left corner of the rectangle.|
| y    | number | Yes   | 0    | Y-coordinate of the upper left corner of the rectangle.|
| w    | number | Yes   | 0    | Width of the rectangle.    |
| h    | number | Yes   | 0    | Height of the rectangle.    |
Z
zengyawen 已提交
720

E
ester.zhou 已提交
721
**Example**
H
HelloCrease 已提交
722

723 724
  ```ts
  // xxx.ets
Z
zengyawen 已提交
725 726 727
  @Entry
  @Component
  struct StrokeRect {
E
ester.zhou 已提交
728 729
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
730

Z
zengyawen 已提交
731 732 733 734 735 736 737 738 739
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.strokeRect(30, 30, 200, 150)
        })
Z
zengyawen 已提交
740
      }
Z
zengyawen 已提交
741 742
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
743
    }
Z
zengyawen 已提交
744 745
  }
  ```
Z
zengyawen 已提交
746

Z
zengyawen 已提交
747
  ![en-us_image_0000001257138359](figures/en-us_image_0000001257138359.png)
Z
zengyawen 已提交
748 749


Z
zengyawen 已提交
750
### clearRect
Z
zengyawen 已提交
751

Z
zengyawen 已提交
752
clearRect(x: number, y: number, w: number, h: number): void
Z
zengyawen 已提交
753 754 755

Clears the content in a rectangle on the canvas.

E
ester.zhou 已提交
756 757
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
758 759 760 761 762 763 764 765
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description           |
| ---- | ------ | ---- | ---- | ------------- |
| x    | number | Yes   | 0    | X-coordinate of the upper left corner of the rectangle.|
| y    | number | Yes   | 0    | Y-coordinate of the upper left corner of the rectangle.|
| w    | number | Yes   | 0    | Width of the rectangle.     |
| h    | number | Yes   | 0    | Height of the rectangle.     |
Z
zengyawen 已提交
766

E
ester.zhou 已提交
767
**Example**
H
HelloCrease 已提交
768

769 770
  ```ts
  // xxx.ets
Z
zengyawen 已提交
771 772 773
  @Entry
  @Component
  struct ClearRect {
E
ester.zhou 已提交
774 775
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
776

Z
zengyawen 已提交
777 778 779 780 781
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
E
ester.zhou 已提交
782
          .backgroundColor('#ffff00')
Z
zengyawen 已提交
783 784
          .onReady(() =>{
            this.context.fillStyle = 'rgb(0,0,255)'
E
esterzhou 已提交
785 786
            this.context.fillRect(20,20,200,200)
            this.context.clearRect(30,30,150,100)
Z
zengyawen 已提交
787
        })
Z
zengyawen 已提交
788
      }
Z
zengyawen 已提交
789 790
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
791
    }
Z
zengyawen 已提交
792 793
  }
  ```
Z
zengyawen 已提交
794

Z
zengyawen 已提交
795
  ![en-us_image_0000001211898482](figures/en-us_image_0000001211898482.png)
Z
zengyawen 已提交
796 797


Z
zengyawen 已提交
798
### fillText
Z
zengyawen 已提交
799

E
ester.zhou 已提交
800
fillText(text: string, x: number, y: number, maxWidth?: number): void
Z
zengyawen 已提交
801 802 803

Draws filled text on the canvas.

E
ester.zhou 已提交
804 805
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
806 807
**Parameters**

E
ester.zhou 已提交
808 809 810 811 812 813
| Name    | Type  | Mandatory| Default Value| Description                         |
| -------- | ------ | ---- | ------ | ----------------------------- |
| text     | string | Yes  | ''     | Text to draw.         |
| x        | number | Yes  | 0      | X-coordinate of the lower left corner of the text.|
| y        | number | Yes  | 0      | Y-coordinate of the lower left corner of the text.|
| maxWidth | number | No  | -      | Maximum width allowed for the text.     |
Z
zengyawen 已提交
814

E
ester.zhou 已提交
815
**Example**
H
HelloCrease 已提交
816

817 818
  ```ts
  // xxx.ets
Z
zengyawen 已提交
819 820 821
  @Entry
  @Component
  struct FillText {
E
ester.zhou 已提交
822 823
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
824

Z
zengyawen 已提交
825 826 827 828 829 830 831 832 833 834
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.font = '30px sans-serif'
            this.context.fillText("Hello World!", 20, 100)
        })
Z
zengyawen 已提交
835
      }
Z
zengyawen 已提交
836 837
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
838
    }
Z
zengyawen 已提交
839 840
  }
  ```
Z
zengyawen 已提交
841

Z
zengyawen 已提交
842
  ![en-us_image_0000001257058399](figures/en-us_image_0000001257058399.png)
Z
zengyawen 已提交
843 844


Z
zengyawen 已提交
845
### strokeText
Z
zengyawen 已提交
846

E
ester.zhou 已提交
847
strokeText(text: string, x: number, y: number, maxWidth?:number): void
Z
zengyawen 已提交
848 849 850

Draws a text stroke on the canvas.

E
ester.zhou 已提交
851 852
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
853 854
**Parameters**

E
ester.zhou 已提交
855 856 857 858 859 860
| Name    | Type  | Mandatory| Default Value| Description                         |
| -------- | ------ | ---- | ------ | ----------------------------- |
| text     | string | Yes  | ''     | Text to draw.         |
| x        | number | Yes  | 0      | X-coordinate of the lower left corner of the text.|
| y        | number | Yes  | 0      | Y-coordinate of the lower left corner of the text.|
| maxWidth | number | No  | -      | Maximum width of the text to be drawn.  |
Z
zengyawen 已提交
861

E
ester.zhou 已提交
862
**Example**
H
HelloCrease 已提交
863

864 865
  ```ts
  // xxx.ets
Z
zengyawen 已提交
866 867 868
  @Entry
  @Component
  struct StrokeText {
E
ester.zhou 已提交
869 870
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
871

Z
zengyawen 已提交
872 873 874 875 876 877 878 879 880 881
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.font = '55px sans-serif'
            this.context.strokeText("Hello World!", 20, 60)
        })
Z
zengyawen 已提交
882
      }
Z
zengyawen 已提交
883 884
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
885
    }
Z
zengyawen 已提交
886 887 888 889 890 891 892 893 894 895
  }
  ```

  ![en-us_image_0000001256978349](figures/en-us_image_0000001256978349.png)


### measureText

measureText(text: string): TextMetrics

E
ester.zhou 已提交
896 897
Measures the specified text to obtain its width. This API returns a **TextMetrics** object.

E
ester.zhou 已提交
898 899
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
900
**Parameters**
Z
zengyawen 已提交
901

E
ester.zhou 已提交
902 903 904
| Name| Type  | Mandatory| Default Value| Description                |
| ---- | ------ | ---- | ------ | -------------------- |
| text | string | Yes  | ''     | Text to be measured.|
Z
zengyawen 已提交
905

E
ester.zhou 已提交
906
**Return value**
Z
zengyawen 已提交
907

E
ester.zhou 已提交
908 909 910
| Type       | Description                                                        |
| ----------- | ------------------------------------------------------------ |
| TextMetrics | **TextMetrics** object.<br>Since API version 9, this API is supported in ArkTS widgets.|
Z
zengyawen 已提交
911

E
ester.zhou 已提交
912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933
**TextMetrics**

| Attribute                      | Type    | Description                                      |
| ------------------------ | ------ | ---------------------------------------- |
| width                    | number | Width of the text.                                 |
| height                   | number | Height of the text.                                 |
| actualBoundingBoxAscent  | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the top of the bounding rectangle used to render the text. The current value is **0**.|
| actualBoundingBoxDescent | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the bottom of the bounding rectangle used to render the text. The current value is **0**.|
| actualBoundingBoxLeft    | number | Distance parallel to the baseline from the alignment point determined by the **CanvasRenderingContext2D.textAlign** attribute to the left side of the bounding rectangle of the text. The current value is **0**.|
| actualBoundingBoxRight   | number | Distance parallel to the baseline from the alignment point determined by the **CanvasRenderingContext2D.textAlign** attribute to the right side of the bounding rectangle of the text. The current value is **0**.|
| alphabeticBaseline       | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the alphabetic baseline of the line box. The current value is **0**.|
| emHeightAscent           | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the top of the em square in the line box. The current value is **0**.|
| emHeightDescent          | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the bottom of the em square in the line box. The current value is **0**.|
| fontBoundingBoxAscent    | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the top of the highest bounding rectangle of all the fonts used to render the text. The current value is **0**.|
| fontBoundingBoxDescent   | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the bottom of the bounding rectangle of all the fonts used to render the text. The current value is **0**.|
| hangingBaseline          | number | Distance from the horizontal line specified by the **CanvasRenderingContext2D.textBaseline** attribute to the hanging baseline of the line box. The current value is **0**.|
| ideographicBaseline      | number | Distance from the horizontal line indicated by the **CanvasRenderingContext2D.textBaseline** attribute to the ideographic baseline of the line box. The current value is **0**.|

  


**Example**
H
HelloCrease 已提交
934

935 936
  ```ts
  // xxx.ets
Z
zengyawen 已提交
937 938 939
  @Entry
  @Component
  struct MeasureText {
E
ester.zhou 已提交
940 941
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
942

Z
zengyawen 已提交
943 944 945 946 947 948 949 950 951 952 953
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.font = '50px sans-serif'
            this.context.fillText("Hello World!", 20, 100)
            this.context.fillText("width:" + this.context.measureText("Hello World!").width, 20, 200)
        })
Z
zengyawen 已提交
954
      }
Z
zengyawen 已提交
955 956
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
957
    }
Z
zengyawen 已提交
958 959
  }
  ```
Z
zengyawen 已提交
960

Z
zengyawen 已提交
961
  ![en-us_image_0000001257138343](figures/en-us_image_0000001257138343.png)
Z
zengyawen 已提交
962 963


Z
zengyawen 已提交
964
### stroke
Z
zengyawen 已提交
965

Z
zengyawen 已提交
966
stroke(path?: Path2D): void
Z
zengyawen 已提交
967 968 969

Strokes a path.

E
ester.zhou 已提交
970 971
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
972 973 974 975 976
**Parameters**

| Name  | Type                                      | Mandatory  | Default Value | Description          |
| ---- | ---------------------------------------- | ---- | ---- | ------------ |
| path | [Path2D](ts-components-canvas-path2d.md) | No   | null | A **Path2D** path to draw.|
Z
zengyawen 已提交
977

E
ester.zhou 已提交
978
**Example**
H
HelloCrease 已提交
979

980 981
  ```ts
  // xxx.ets
Z
zengyawen 已提交
982 983 984
  @Entry
  @Component
  struct Stroke {
E
ester.zhou 已提交
985 986
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
987

Z
zengyawen 已提交
988 989 990 991 992 993 994 995 996
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.moveTo(25, 25)
            this.context.lineTo(25, 105)
E
esterzhou 已提交
997 998
            this.context.lineTo(75, 105)
            this.context.lineTo(75, 25)
Z
zengyawen 已提交
999 1000 1001
            this.context.strokeStyle = 'rgb(0,0,255)'
            this.context.stroke()
          })
Z
zengyawen 已提交
1002
      }
Z
zengyawen 已提交
1003 1004
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1005
    }
Z
zengyawen 已提交
1006 1007
  }
  ```
Z
zengyawen 已提交
1008

Z
zengyawen 已提交
1009
  ![en-us_image_0000001257058411](figures/en-us_image_0000001257058411.png)
Z
zengyawen 已提交
1010 1011


Z
zengyawen 已提交
1012
### beginPath
Z
zengyawen 已提交
1013

Z
zengyawen 已提交
1014
beginPath(): void
Z
zengyawen 已提交
1015 1016 1017

Creates a drawing path.

E
ester.zhou 已提交
1018 1019
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1020
**Example**
H
HelloCrease 已提交
1021

1022 1023
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1024 1025 1026
  @Entry
  @Component
  struct BeginPath {
E
ester.zhou 已提交
1027 1028
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1029

Z
zengyawen 已提交
1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
            this.context.lineWidth = 6
            this.context.strokeStyle = '#0000ff'
            this.context.moveTo(15, 80)
            this.context.lineTo(280, 160)
            this.context.stroke()
          })
Z
zengyawen 已提交
1044
      }
Z
zengyawen 已提交
1045 1046
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1047
    }
Z
zengyawen 已提交
1048 1049
  }
  ```
Z
zengyawen 已提交
1050

Z
zengyawen 已提交
1051
  ![en-us_image_0000001212058478](figures/en-us_image_0000001212058478.png)
Z
zengyawen 已提交
1052 1053


Z
zengyawen 已提交
1054
### moveTo
Z
zengyawen 已提交
1055

Z
zengyawen 已提交
1056
moveTo(x: number, y: number): void
Z
zengyawen 已提交
1057 1058 1059

Moves a drawing path to a target position on the canvas.

E
ester.zhou 已提交
1060 1061
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1062 1063 1064 1065 1066 1067
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description       |
| ---- | ------ | ---- | ---- | --------- |
| x    | number | Yes   | 0    | X-coordinate of the target position.|
| y    | number | Yes   | 0    | Y-coordinate of the target position.|
Z
zengyawen 已提交
1068

E
ester.zhou 已提交
1069
**Example**
H
HelloCrease 已提交
1070

1071 1072
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1073 1074 1075
  @Entry
  @Component
  struct MoveTo {
E
ester.zhou 已提交
1076 1077
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1078

Z
zengyawen 已提交
1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
            this.context.moveTo(10, 10)
            this.context.lineTo(280, 160)
            this.context.stroke()
          })
Z
zengyawen 已提交
1091
      }
Z
zengyawen 已提交
1092 1093
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1094
    }
Z
zengyawen 已提交
1095 1096
  }
  ```
Z
zengyawen 已提交
1097

Z
zengyawen 已提交
1098
  ![en-us_image_0000001256858391](figures/en-us_image_0000001256858391.png)
Z
zengyawen 已提交
1099 1100


Z
zengyawen 已提交
1101
### lineTo
Z
zengyawen 已提交
1102

Z
zengyawen 已提交
1103
lineTo(x: number, y: number): void
Z
zengyawen 已提交
1104 1105 1106

Connects the current point to a target position using a straight line.

E
ester.zhou 已提交
1107 1108
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1109 1110 1111 1112 1113 1114
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description       |
| ---- | ------ | ---- | ---- | --------- |
| x    | number | Yes   | 0    | X-coordinate of the target position.|
| y    | number | Yes   | 0    | Y-coordinate of the target position.|
Z
zengyawen 已提交
1115

E
ester.zhou 已提交
1116
**Example**
H
HelloCrease 已提交
1117

1118 1119
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1120 1121 1122
  @Entry
  @Component
  struct LineTo {
E
ester.zhou 已提交
1123 1124
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1125

Z
zengyawen 已提交
1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
            this.context.moveTo(10, 10)
            this.context.lineTo(280, 160)
            this.context.stroke()
          })
Z
zengyawen 已提交
1138
      }
Z
zengyawen 已提交
1139 1140
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1141
    }
Z
zengyawen 已提交
1142 1143
  }
  ```
Z
zengyawen 已提交
1144

Z
zengyawen 已提交
1145
  ![en-us_image_0000001212378414](figures/en-us_image_0000001212378414.png)
Z
zengyawen 已提交
1146 1147


Z
zengyawen 已提交
1148
### closePath
Z
zengyawen 已提交
1149

Z
zengyawen 已提交
1150
closePath(): void
Z
zengyawen 已提交
1151 1152 1153

Draws a closed path.

E
ester.zhou 已提交
1154 1155
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1156
**Example**
H
HelloCrease 已提交
1157

1158 1159
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1160 1161 1162
  @Entry
  @Component
  struct ClosePath {
E
ester.zhou 已提交
1163 1164
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1165

Z
zengyawen 已提交
1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
              this.context.beginPath()
              this.context.moveTo(30, 30)
              this.context.lineTo(110, 30)
              this.context.lineTo(70, 90)
              this.context.closePath()
              this.context.stroke()
          })
Z
zengyawen 已提交
1180
      }
Z
zengyawen 已提交
1181 1182
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1183
    }
Z
zengyawen 已提交
1184 1185
  }
  ```
Z
zengyawen 已提交
1186

Z
zengyawen 已提交
1187
  ![en-us_image_0000001256978347](figures/en-us_image_0000001256978347.png)
Z
zengyawen 已提交
1188 1189


Z
zengyawen 已提交
1190
### createPattern
Z
zengyawen 已提交
1191

E
ester.zhou 已提交
1192
createPattern(image: ImageBitmap, repetition: string | null): CanvasPattern | null
Z
zengyawen 已提交
1193 1194 1195

Creates a pattern for image filling based on a specified source image and repetition mode.

E
ester.zhou 已提交
1196 1197
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1198 1199
**Parameters**

E
ester.zhou 已提交
1200 1201 1202
| Name      | Type                                              | Mandatory| Description                                                        |
| ---------- | -------------------------------------------------- | ---- | ------------------------------------------------------------ |
| image      | [ImageBitmap](ts-components-canvas-imagebitmap.md) | Yes  | Source image. For details, see **ImageBitmap**.                         |
E
ester.zhou 已提交
1203
| repetition | string                                             | Yes  | Repetition mode. The value can be **'repeat'**, **'repeat-x'**, **'repeat-y'**, **'no-repeat'**, **'clamp'**, or **'mirror'**.<br>Default value: **''**|
E
ester.zhou 已提交
1204 1205

**Return value**
Z
zengyawen 已提交
1206

E
ester.zhou 已提交
1207 1208 1209 1210 1211
| Type                             | Description                     |
| ------------------------------- | ----------------------- |
| [CanvasPattern](#canvaspattern) | Created pattern for image filling based on a specified source image and repetition mode.|

**Example**
H
HelloCrease 已提交
1212

1213 1214
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1215 1216 1217
  @Entry
  @Component
  struct CreatePattern {
E
ester.zhou 已提交
1218 1219 1220
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    private img:ImageBitmap = new ImageBitmap("common/images/icon.jpg")
H
HelloCrease 已提交
1221

Z
zengyawen 已提交
1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var pattern = this.context.createPattern(this.img, 'repeat')
            this.context.fillStyle = pattern
            this.context.fillRect(0, 0, 200, 200)
          })
Z
zengyawen 已提交
1233
      }
Z
zengyawen 已提交
1234 1235
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1236
    }
Z
zengyawen 已提交
1237 1238
  }
  ```
Z
zengyawen 已提交
1239

Z
zengyawen 已提交
1240
  ![en-us_image_0000001211898490](figures/en-us_image_0000001211898490.png)
Z
zengyawen 已提交
1241 1242


Z
zengyawen 已提交
1243
### bezierCurveTo
Z
zengyawen 已提交
1244

Z
zengyawen 已提交
1245
bezierCurveTo(cp1x: number, cp1y: number, cp2x: number, cp2y: number, x: number, y: number): void
Z
zengyawen 已提交
1246 1247 1248

Draws a cubic bezier curve on the canvas.

E
ester.zhou 已提交
1249 1250
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1251 1252 1253 1254 1255 1256 1257 1258 1259 1260
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description            |
| ---- | ------ | ---- | ---- | -------------- |
| cp1x | number | Yes   | 0    | X-coordinate of the first parameter of the bezier curve.|
| cp1y | number | Yes   | 0    | Y-coordinate of the first parameter of the bezier curve.|
| cp2x | number | Yes   | 0    | X-coordinate of the second parameter of the bezier curve.|
| cp2y | number | Yes   | 0    | Y-coordinate of the second parameter of the bezier curve.|
| x    | number | Yes   | 0    | X-coordinate of the end point on the bezier curve.   |
| y    | number | Yes   | 0    | Y-coordinate of the end point on the bezier curve.   |
Z
zengyawen 已提交
1261

E
ester.zhou 已提交
1262
**Example**
H
HelloCrease 已提交
1263

1264 1265
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1266 1267 1268
  @Entry
  @Component
  struct BezierCurveTo {
E
ester.zhou 已提交
1269 1270
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1271

Z
zengyawen 已提交
1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
            this.context.moveTo(10, 10)
            this.context.bezierCurveTo(20, 100, 200, 100, 200, 20)
            this.context.stroke()
          })
Z
zengyawen 已提交
1284
      }
Z
zengyawen 已提交
1285 1286
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1287
    }
Z
zengyawen 已提交
1288 1289
  }
  ```
Z
zengyawen 已提交
1290

Z
zengyawen 已提交
1291
  ![en-us_image_0000001257138349](figures/en-us_image_0000001257138349.png)
Z
zengyawen 已提交
1292 1293


Z
zengyawen 已提交
1294
### quadraticCurveTo
Z
zengyawen 已提交
1295

Z
zengyawen 已提交
1296
quadraticCurveTo(cpx: number, cpy: number, x: number, y: number): void
Z
zengyawen 已提交
1297 1298 1299

Draws a quadratic curve on the canvas.

E
ester.zhou 已提交
1300 1301
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1302
**Parameters**
Z
zengyawen 已提交
1303

E
ester.zhou 已提交
1304 1305 1306 1307 1308 1309 1310 1311
| Name  | Type    | Mandatory  | Default Value | Description         |
| ---- | ------ | ---- | ---- | ----------- |
| cpx  | number | Yes   | 0    | X-coordinate of the bezier curve parameter.|
| cpy  | number | Yes   | 0    | Y-coordinate of the bezier curve parameter.|
| x    | number | Yes   | 0    | X-coordinate of the end point on the bezier curve.|
| y    | number | Yes   | 0    | Y-coordinate of the end point on the bezier curve.|

**Example**
H
HelloCrease 已提交
1312

1313 1314
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1315 1316 1317
  @Entry
  @Component
  struct QuadraticCurveTo {
E
ester.zhou 已提交
1318 1319
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
ester.zhou 已提交
1320

Z
zengyawen 已提交
1321 1322 1323 1324 1325 1326 1327
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
1328 1329 1330 1331
            this.context.beginPath()
            this.context.moveTo(20, 20)
            this.context.quadraticCurveTo(100, 100, 200, 20)
            this.context.stroke()
Z
zengyawen 已提交
1332
        })
Z
zengyawen 已提交
1333
      }
Z
zengyawen 已提交
1334 1335
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1336
    }
Z
zengyawen 已提交
1337 1338
  }
  ```
Z
zengyawen 已提交
1339

Z
zengyawen 已提交
1340
  ![en-us_image_0000001257058397](figures/en-us_image_0000001257058397.png)
Z
zengyawen 已提交
1341 1342


Z
zengyawen 已提交
1343
### arc
Z
zengyawen 已提交
1344

E
ester.zhou 已提交
1345
arc(x: number, y: number, radius: number, startAngle: number, endAngle: number, counterclockwise?: boolean): void
Z
zengyawen 已提交
1346 1347 1348

Draws an arc on the canvas.

E
ester.zhou 已提交
1349 1350
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1351 1352 1353 1354 1355 1356 1357 1358 1359 1360
**Parameters**

| Name              | Type     | Mandatory  | Default Value  | Description        |
| ---------------- | ------- | ---- | ----- | ---------- |
| x                | number  | Yes   | 0     | X-coordinate of the center point of the arc.|
| y                | number  | Yes   | 0     | Y-coordinate of the center point of the arc.|
| radius           | number  | Yes   | 0     | Radius of the arc.   |
| startAngle       | number  | Yes   | 0     | Start radian of the arc.  |
| endAngle         | number  | Yes   | 0     | End radian of the arc.  |
| counterclockwise | boolean | No   | false | Whether to draw the arc counterclockwise.|
Z
zengyawen 已提交
1361

E
ester.zhou 已提交
1362
**Example**
H
HelloCrease 已提交
1363

E
ester.zhou 已提交
1364 1365
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1366 1367 1368
  @Entry
  @Component
  struct Arc {
E
ester.zhou 已提交
1369 1370
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1371

Z
zengyawen 已提交
1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
            this.context.arc(100, 75, 50, 0, 6.28)
            this.context.stroke()
          })
Z
zengyawen 已提交
1383
      }
Z
zengyawen 已提交
1384 1385
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1386
    }
Z
zengyawen 已提交
1387 1388
  }
  ```
Z
zengyawen 已提交
1389

Z
zengyawen 已提交
1390
  ![en-us_image_0000001212378404](figures/en-us_image_0000001212378404.png)
Z
zengyawen 已提交
1391 1392


Z
zengyawen 已提交
1393
### arcTo
Z
zengyawen 已提交
1394

Z
zengyawen 已提交
1395
arcTo(x1: number, y1: number, x2: number, y2: number, radius: number): void
Z
zengyawen 已提交
1396 1397 1398

Draws an arc based on the radius and points on the arc.

E
ester.zhou 已提交
1399 1400
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1401
**Parameters**
Z
zengyawen 已提交
1402

E
ester.zhou 已提交
1403 1404 1405 1406 1407 1408 1409 1410 1411
| Name    | Type    | Mandatory  | Default Value | Description             |
| ------ | ------ | ---- | ---- | --------------- |
| x1     | number | Yes   | 0    | X-coordinate of the first point on the arc.|
| y1     | number | Yes   | 0    | Y-coordinate of the first point on the arc.|
| x2     | number | Yes   | 0    | X-coordinate of the second point on the arc.|
| y2     | number | Yes   | 0    | Y-coordinate of the second point on the arc.|
| radius | number | Yes   | 0    | Radius of the arc.       |

**Example**
H
HelloCrease 已提交
1412

1413 1414
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1415 1416 1417
  @Entry
  @Component
  struct ArcTo {
E
ester.zhou 已提交
1418 1419
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1420

Z
zengyawen 已提交
1421 1422 1423 1424 1425 1426 1427
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
1428 1429 1430
            this.context.moveTo(100, 20)
            this.context.arcTo(150, 20, 150, 70, 50)
            this.context.stroke()
Z
zengyawen 已提交
1431
          })
Z
zengyawen 已提交
1432
      }
Z
zengyawen 已提交
1433 1434
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1435
    }
Z
zengyawen 已提交
1436 1437
  }
  ```
Z
zengyawen 已提交
1438

Z
zengyawen 已提交
1439
  ![en-us_image_0000001257058413](figures/en-us_image_0000001257058413.png)
Z
zengyawen 已提交
1440 1441


Z
zengyawen 已提交
1442
### ellipse
Z
zengyawen 已提交
1443

E
ester.zhou 已提交
1444
ellipse(x: number, y: number, radiusX: number, radiusY: number, rotation: number, startAngle: number, endAngle: number, counterclockwise?: boolean): void
Z
zengyawen 已提交
1445

E
ester.zhou 已提交
1446
Draws an ellipse in the specified rectangular region on the canvas.
Z
zengyawen 已提交
1447

E
ester.zhou 已提交
1448 1449
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1450
**Parameters**
Z
zengyawen 已提交
1451

E
ester.zhou 已提交
1452 1453 1454 1455 1456 1457 1458 1459 1460
| Name              | Type     | Mandatory  | Default Value  | Description               |
| ---------------- | ------- | ---- | ----- | ----------------- |
| x                | number  | Yes   | 0     | X-coordinate of the ellipse center.       |
| y                | number  | Yes   | 0     | Y-coordinate of the ellipse center.       |
| radiusX          | number  | Yes   | 0     | Ellipse radius on the x-axis.       |
| radiusY          | number  | Yes   | 0     | Ellipse radius on the y-axis.       |
| rotation         | number  | Yes   | 0     | Rotation angle of the ellipse. The unit is radian.   |
| startAngle       | number  | Yes   | 0     | Angle of the start point for drawing the ellipse. The unit is radian.|
| endAngle         | number  | Yes   | 0     | Angle of the end point for drawing the ellipse. The unit is radian.|
E
ester.zhou 已提交
1461
| counterclockwise | boolean | No   | false | Whether to draw the ellipse in the counterclockwise direction.<br>**true**: Draw the arc counterclockwise.<br>**false**: Draw the arc clockwise.    |
Z
zengyawen 已提交
1462

E
ester.zhou 已提交
1463
**Example**
H
HelloCrease 已提交
1464

1465 1466
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1467 1468 1469
  @Entry
  @Component
  struct CanvasExample {
E
ester.zhou 已提交
1470 1471
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1472

Z
zengyawen 已提交
1473 1474 1475 1476 1477 1478 1479 1480
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.beginPath()
E
esterzhou 已提交
1481
            this.context.ellipse(200, 200, 50, 100, Math.PI * 0.25, Math.PI * 0.5, Math.PI * 2)
Z
zengyawen 已提交
1482 1483
            this.context.stroke()
          })
Z
zengyawen 已提交
1484
      }
Z
zengyawen 已提交
1485 1486
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1487
    }
Z
zengyawen 已提交
1488 1489
  }
  ```
Z
zengyawen 已提交
1490

Z
zengyawen 已提交
1491
  ![en-us_image_0000001256978339](figures/en-us_image_0000001256978339.png)
Z
zengyawen 已提交
1492 1493


Z
zengyawen 已提交
1494
### rect
Z
zengyawen 已提交
1495

E
ester.zhou 已提交
1496 1497 1498
rect(x: number, y: number, w: number, h: number): void

Creates a rectangle on the canvas.
Z
zengyawen 已提交
1499

E
ester.zhou 已提交
1500 1501
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1502
**Parameters**
Z
zengyawen 已提交
1503

E
ester.zhou 已提交
1504 1505 1506 1507 1508 1509
| Name  | Type    | Mandatory  | Default Value | Description           |
| ---- | ------ | ---- | ---- | ------------- |
| x    | number | Yes   | 0    | X-coordinate of the upper left corner of the rectangle.|
| y    | number | Yes   | 0    | Y-coordinate of the upper left corner of the rectangle.|
| w    | number | Yes   | 0    | Width of the rectangle.     |
| h    | number | Yes   | 0    | Height of the rectangle.     |
Z
zengyawen 已提交
1510

E
ester.zhou 已提交
1511
**Example**
H
HelloCrease 已提交
1512

1513 1514
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1515 1516 1517
  @Entry
  @Component
  struct CanvasExample {
E
ester.zhou 已提交
1518 1519
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1520

Z
zengyawen 已提交
1521 1522 1523 1524 1525 1526 1527 1528 1529 1530
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.rect(20, 20, 100, 100) // Create a 100*100 rectangle at (20, 20)
            this.context.stroke()
          })
Z
zengyawen 已提交
1531
      }
Z
zengyawen 已提交
1532 1533
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1534
    }
Z
zengyawen 已提交
1535 1536
  }
  ```
Z
zengyawen 已提交
1537

Z
zengyawen 已提交
1538
  ![en-us_image_0000001256978341](figures/en-us_image_0000001256978341.png)
Z
zengyawen 已提交
1539 1540


Z
zengyawen 已提交
1541
### fill
Z
zengyawen 已提交
1542

E
ester.zhou 已提交
1543 1544 1545 1546
fill(fillRule?: CanvasFillRule): void

Fills the area inside a closed path on the canvas.

E
ester.zhou 已提交
1547 1548
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1549
**Parameters**
Z
zengyawen 已提交
1550

E
ester.zhou 已提交
1551 1552
| Name      | Type            | Mandatory  | Default Value      | Description                                      |
| -------- | -------------- | ---- | --------- | ---------------------------------------- |
E
esterzhou 已提交
1553
| fillRule | CanvasFillRule | No   | "nonzero" | Rule by which to determine whether a point is inside or outside the area to fill.<br>The options are **"nonzero"** and **"evenodd"**.|
Z
zengyawen 已提交
1554

E
ester.zhou 已提交
1555 1556

**Example**  
H
HelloCrease 已提交
1557

1558 1559
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1560 1561 1562
  @Entry
  @Component
  struct Fill {
E
ester.zhou 已提交
1563 1564
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1565

Z
zengyawen 已提交
1566 1567 1568 1569 1570 1571 1572 1573 1574 1575
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.rect(20, 20, 100, 100) // Create a 100*100 rectangle at (20, 20)
            this.context.fill()
          })
Z
zengyawen 已提交
1576
      }
Z
zengyawen 已提交
1577 1578
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1579
    }
Z
zengyawen 已提交
1580 1581
  }
  ```
Z
zengyawen 已提交
1582

Z
zengyawen 已提交
1583
  ![en-us_image_0000001256858389](figures/en-us_image_0000001256858389.png)
Z
zengyawen 已提交
1584 1585


E
ester.zhou 已提交
1586 1587 1588 1589
fill(path: Path2D, fillRule?: CanvasFillRule): void

Fills the area inside a closed path on the canvas.

E
ester.zhou 已提交
1590 1591
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616
**Parameters**

| Name      | Type            | Mandatory  | Default Value      | Description                                      |
| -------- | -------------- | ---- | --------- | ---------------------------------------- |
| path     | Path2D         | Yes   |           | A **Path2D** path to fill.                             |
| fillRule | CanvasFillRule | No   | "nonzero" | Rule by which to determine whether a point is inside or outside the area to fill.<br>The options are **"nonzero"** and **"evenodd"**.|


**Example**  

```ts
// xxx.ets
@Entry
@Component
struct Fill {
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffff00')
        .onReady(() =>{
E
ester.zhou 已提交
1617 1618 1619 1620 1621 1622 1623 1624
          let region = new Path2D()
          region.moveTo(30, 90)
          region.lineTo(110, 20)
          region.lineTo(240, 130)
          region.lineTo(60, 130)
          region.lineTo(190, 20)
          region.lineTo(270, 90)
          region.closePath()
E
ester.zhou 已提交
1625
          // Fill path
E
ester.zhou 已提交
1626
          this.context.fillStyle = '#00ff00'
E
ester.zhou 已提交
1627
          this.context.fill(region, "evenodd")
E
ester.zhou 已提交
1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638
        })
    }
    .width('100%')
    .height('100%')
  }
}
```

 ![en-us_image_000000127777774](figures/en-us_image_000000127777774.png)


Z
zengyawen 已提交
1639
### clip
Z
zengyawen 已提交
1640

E
ester.zhou 已提交
1641 1642 1643
clip(fillRule?: CanvasFillRule): void

Sets the current path to a clipping area.
Z
zengyawen 已提交
1644

E
ester.zhou 已提交
1645 1646
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1647
**Parameters**
Z
zengyawen 已提交
1648

E
ester.zhou 已提交
1649 1650 1651 1652 1653
| Name      | Type            | Mandatory  | Default Value      | Description                                      |
| -------- | -------------- | ---- | --------- | ---------------------------------------- |
| fillRule | CanvasFillRule | No   | "nonzero" | Rule by which to determine whether a point is inside or outside the area to clip.<br>The options are **"nonzero"** and **"evenodd"**.|

**Example**
H
HelloCrease 已提交
1654

1655 1656
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1657 1658 1659
  @Entry
  @Component
  struct Clip {
E
ester.zhou 已提交
1660 1661
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1662

Z
zengyawen 已提交
1663 1664 1665 1666 1667 1668 1669
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
esterzhou 已提交
1670
            this.context.rect(0, 0, 100, 200)
Z
zengyawen 已提交
1671 1672 1673
            this.context.stroke()
            this.context.clip()
            this.context.fillStyle = "rgb(255,0,0)"
E
esterzhou 已提交
1674
            this.context.fillRect(0, 0, 200, 200)
Z
zengyawen 已提交
1675
          })
Z
zengyawen 已提交
1676
      }
Z
zengyawen 已提交
1677 1678
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1679
    }
Z
zengyawen 已提交
1680 1681
  }
  ```
Z
zengyawen 已提交
1682

Z
zengyawen 已提交
1683
  ![en-us_image_0000001211898488](figures/en-us_image_0000001211898488.png)
Z
zengyawen 已提交
1684 1685


E
ester.zhou 已提交
1686 1687
clip(path: Path2D, fillRule?: CanvasFillRule): void

E
esterzhou 已提交
1688
Sets the current path to a clipping path.
E
ester.zhou 已提交
1689

E
ester.zhou 已提交
1690 1691
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1692 1693 1694 1695 1696 1697 1698 1699
**Parameters**

| Name      | Type            | Mandatory  | Default Value      | Description                                      |
| -------- | -------------- | ---- | --------- | ---------------------------------------- |
| path     | Path2D         | Yes   | -         | A **Path2D** path to use as a clipping area.                             |
| fillRule | CanvasFillRule | No   | "nonzero" | Rule by which to determine whether a point is inside or outside the area to clip.<br>The options are **"nonzero"** and **"evenodd"**.|


E
esterzhou 已提交
1700 1701 1702 1703
**Example**

  ```ts
  // xxx.ets
E
ester.zhou 已提交
1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730
  @Entry
  @Component
  struct Clip {
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            let region = new Path2D()
            region.moveTo(30, 90)
            region.lineTo(110, 20)
            region.lineTo(240, 130)
            region.lineTo(60, 130)
            region.lineTo(190, 20)
            region.lineTo(270, 90)
            region.closePath()
            this.context.clip(region,"evenodd")
            this.context.fillStyle = "rgb(0,255,0)"
            this.context.fillRect(0, 0, this.context.width, this.context.height)
          })
      }
      .width('100%')
      .height('100%')
E
esterzhou 已提交
1731 1732 1733 1734 1735 1736
    }
  }
  ```

  ![en-us_image_000000127777779](figures/en-us_image_000000127777779.png)

E
ester.zhou 已提交
1737 1738 1739 1740 1741

### filter

filter(filter: string): void

E
esterzhou 已提交
1742
Provides filter effects. This API is a void API.
E
ester.zhou 已提交
1743

E
ester.zhou 已提交
1744 1745
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756
**Parameters**

| Name    | Type    | Mandatory  | Default Value | Description          |
| ------ | ------ | ---- | ---- | ------------ |
| filter | string | Yes   | -    | Filter functions.|


### getTransform

getTransform(): Matrix2D

E
esterzhou 已提交
1757
Obtains the current transformation matrix being applied to the context. This API is a void API.
E
ester.zhou 已提交
1758

E
ester.zhou 已提交
1759 1760
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1761 1762 1763 1764 1765

### resetTransform

resetTransform(): void

E
esterzhou 已提交
1766
Resets the current transform to the identity matrix. This API is a void API.
E
ester.zhou 已提交
1767

E
ester.zhou 已提交
1768 1769
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1770 1771 1772 1773 1774

### direction

direction(direction: CanvasDirection): void

E
esterzhou 已提交
1775
Sets the current text direction used to draw text. This API is a void API.
E
ester.zhou 已提交
1776

E
ester.zhou 已提交
1777 1778
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1779

Z
zengyawen 已提交
1780
### rotate
Z
zengyawen 已提交
1781

E
ester.zhou 已提交
1782
rotate(angle: number): void
Z
zengyawen 已提交
1783 1784 1785

Rotates a canvas clockwise around its coordinate axes.

E
ester.zhou 已提交
1786 1787
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1788
**Parameters**
Z
zengyawen 已提交
1789

E
ester.zhou 已提交
1790 1791 1792 1793 1794
| Name   | Type    | Mandatory  | Default Value | Description                                      |
| ----- | ------ | ---- | ---- | ---------------------------------------- |
| angle | number | Yes   | 0    | Clockwise rotation angle. You can use **Math.PI / 180** to convert the angle to a radian.|

**Example**
H
HelloCrease 已提交
1795

1796 1797
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1798 1799 1800
  @Entry
  @Component
  struct Rotate {
E
ester.zhou 已提交
1801 1802
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1803

Z
zengyawen 已提交
1804 1805 1806 1807 1808 1809 1810
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
1811
            this.context.rotate(45 * Math.PI / 180)
Z
zengyawen 已提交
1812 1813
            this.context.fillRect(70, 20, 50, 50)
          })
Z
zengyawen 已提交
1814
      }
Z
zengyawen 已提交
1815 1816
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1817
    }
Z
zengyawen 已提交
1818 1819 1820 1821 1822 1823 1824 1825 1826 1827
  }
  ```

  ![en-us_image_0000001212218442](figures/en-us_image_0000001212218442.png)


### scale

scale(x: number, y: number): void

E
ester.zhou 已提交
1828
Scales the canvas based on the given scale factors.
Z
zengyawen 已提交
1829

E
ester.zhou 已提交
1830 1831
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1832
**Parameters**
Z
zengyawen 已提交
1833

E
ester.zhou 已提交
1834 1835 1836 1837 1838 1839
| Name  | Type    | Mandatory  | Default Value | Description         |
| ---- | ------ | ---- | ---- | ----------- |
| x    | number | Yes   | 0    | Horizontal scale factor.|
| y    | number | Yes   | 0    | Vertical scale factor.|

**Example**
H
HelloCrease 已提交
1840

1841 1842
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1843 1844 1845
  @Entry
  @Component
  struct Scale {
E
ester.zhou 已提交
1846 1847
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1848

Z
zengyawen 已提交
1849 1850 1851 1852 1853 1854 1855
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
esterzhou 已提交
1856 1857
            this.context.lineWidth = 3
            this.context.strokeRect(30, 30, 50, 50)
Z
zengyawen 已提交
1858
            this.context.scale(2, 2) // Scale to 200%
E
esterzhou 已提交
1859
            this.context.strokeRect(30, 30, 50, 50)
Z
zengyawen 已提交
1860
          })
Z
zengyawen 已提交
1861
      }
Z
zengyawen 已提交
1862 1863
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1864
    }
Z
zengyawen 已提交
1865 1866
  }
  ```
Z
zengyawen 已提交
1867

Z
zengyawen 已提交
1868
  ![en-us_image_0000001257138347](figures/en-us_image_0000001257138347.png)
Z
zengyawen 已提交
1869 1870


Z
zengyawen 已提交
1871
### transform
Z
zengyawen 已提交
1872

E
ester.zhou 已提交
1873
transform(a: number, b: number, c: number, d: number, e: number, f: number): void
Z
zengyawen 已提交
1874 1875 1876

Defines a transformation matrix. To transform a graph, you only need to set parameters of the matrix. The coordinates of the graph are multiplied by the matrix values to obtain new coordinates of the transformed graph. You can use the matrix to implement multiple transform effects.

E
ester.zhou 已提交
1877 1878
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1879
> **NOTE**
E
ester.zhou 已提交
1880
>
Z
zengyawen 已提交
1881
> The following formulas calculate coordinates of the transformed graph. **x** and **y** represent coordinates before transformation, and **x'** and **y'** represent coordinates after transformation.
H
HelloCrease 已提交
1882
>
Z
zengyawen 已提交
1883
> - x' = scaleX \* x + skewY \* y + translateX
H
HelloCrease 已提交
1884
>
Z
zengyawen 已提交
1885 1886
> - y' = skewX \* x + scaleY \* y + translateY

E
ester.zhou 已提交
1887 1888 1889 1890 1891 1892 1893 1894 1895 1896
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description                  |
| ---- | ------ | ---- | ---- | -------------------- |
| a    | number | Yes   | 0    | X-axis scale.    |
| b    | number | Yes   | 0    | X-axis skew.     |
| c    | number | Yes   | 0    | Y-axis skew.     |
| d    | number | Yes   | 0    | Y-axis scale.    |
| e    | number | Yes   | 0    | X-axis translation.|
| f    | number | Yes   | 0    | Y-axis translation.|
Z
zengyawen 已提交
1897

E
ester.zhou 已提交
1898
**Example**
H
HelloCrease 已提交
1899

1900 1901
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1902 1903 1904
  @Entry
  @Component
  struct Transform {
E
ester.zhou 已提交
1905 1906
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1907

Z
zengyawen 已提交
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.fillStyle = 'rgb(0,0,0)'
            this.context.fillRect(0, 0, 100, 100)
            this.context.transform(1, 0.5, -0.5, 1, 10, 10)
            this.context.fillStyle = 'rgb(255,0,0)'
            this.context.fillRect(0, 0, 100, 100)
            this.context.transform(1, 0.5, -0.5, 1, 10, 10)
            this.context.fillStyle = 'rgb(0,0,255)'
            this.context.fillRect(0, 0, 100, 100)
          })
Z
zengyawen 已提交
1924
      }
Z
zengyawen 已提交
1925 1926
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1927
    }
Z
zengyawen 已提交
1928 1929 1930 1931 1932 1933 1934 1935
  }
  ```

  ![en-us_image_0000001256858393](figures/en-us_image_0000001256858393.png)


### setTransform

E
ester.zhou 已提交
1936
setTransform(a: number, b: number, c: number, d: number, e: number, f: number): void
Z
zengyawen 已提交
1937

E
ester.zhou 已提交
1938
Resets the existing transformation matrix and creates a new transformation matrix by using the same parameters as the **transform()** API.
Z
zengyawen 已提交
1939

E
ester.zhou 已提交
1940 1941
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
1942
**Parameters**
Z
zengyawen 已提交
1943

E
ester.zhou 已提交
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953
| Name  | Type    | Mandatory  | Default Value | Description                  |
| ---- | ------ | ---- | ---- | -------------------- |
| a    | number | Yes   | 0    | X-axis scale.    |
| b    | number | Yes   | 0    | X-axis skew.     |
| c    | number | Yes   | 0    | Y-axis skew.     |
| d    | number | Yes   | 0    | Y-axis scale.    |
| e    | number | Yes   | 0    | X-axis translation.|
| f    | number | Yes   | 0    | Y-axis translation.|

**Example**
H
HelloCrease 已提交
1954

1955 1956
  ```ts
  // xxx.ets
Z
zengyawen 已提交
1957 1958 1959
  @Entry
  @Component
  struct SetTransform {
E
ester.zhou 已提交
1960 1961
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
1962

Z
zengyawen 已提交
1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.fillStyle = 'rgb(255,0,0)'
            this.context.fillRect(0, 0, 100, 100)
            this.context.setTransform(1,0.5, -0.5, 1, 10, 10)
            this.context.fillStyle = 'rgb(0,0,255)'
            this.context.fillRect(0, 0, 100, 100)
          })
Z
zengyawen 已提交
1976
      }
Z
zengyawen 已提交
1977 1978
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
1979
    }
Z
zengyawen 已提交
1980 1981
  }
  ```
Z
zengyawen 已提交
1982

Z
zengyawen 已提交
1983
  ![en-us_image_0000001256858395](figures/en-us_image_0000001256858395.png)
Z
zengyawen 已提交
1984 1985


E
ester.zhou 已提交
1986 1987
setTransform(transform?: Matrix2D): void

E
esterzhou 已提交
1988
Resets the current transformation to the identity matrix, and then creates a new transformation matrix based on the specified **Matrix2D** object. This API is a void API.
E
ester.zhou 已提交
1989

E
ester.zhou 已提交
1990
Since API version 9, this API is supported in ArkTS widgets.
E
ester.zhou 已提交
1991

E
ester.zhou 已提交
1992

Z
zengyawen 已提交
1993
### translate
Z
zengyawen 已提交
1994

Z
zengyawen 已提交
1995
translate(x: number, y: number): void
Z
zengyawen 已提交
1996 1997 1998

Moves the origin of the coordinate system.

E
ester.zhou 已提交
1999 2000
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2001 2002 2003 2004 2005 2006
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description      |
| ---- | ------ | ---- | ---- | -------- |
| x    | number | Yes   | 0    | X-axis translation.|
| y    | number | Yes   | 0    | Y-axis translation.|
Z
zengyawen 已提交
2007

E
ester.zhou 已提交
2008
**Example**
H
HelloCrease 已提交
2009

2010 2011
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2012 2013 2014
  @Entry
  @Component
  struct Translate {
E
ester.zhou 已提交
2015 2016
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
2017

Z
zengyawen 已提交
2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.fillRect(10, 10, 50, 50)
            this.context.translate(70, 70)
            this.context.fillRect(10, 10, 50, 50)
          })
Z
zengyawen 已提交
2029
      }
Z
zengyawen 已提交
2030 2031
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2032
    }
Z
zengyawen 已提交
2033 2034
  }
  ```
Z
zengyawen 已提交
2035

Z
zengyawen 已提交
2036
  ![en-us_image_0000001257138357](figures/en-us_image_0000001257138357.png)
Z
zengyawen 已提交
2037 2038


Z
zengyawen 已提交
2039
### drawImage
Z
zengyawen 已提交
2040

2041
drawImage(image: ImageBitmap | PixelMap, dx: number, dy: number): void
Z
zengyawen 已提交
2042

E
ester.zhou 已提交
2043 2044 2045
drawImage(image: ImageBitmap | PixelMap, dx: number, dy: number, dw: number, dh: number): void

drawImage(image: ImageBitmap | PixelMap, sx: number, sy: number, sw: number, sh: number, dx: number, dy: number, dw: number, dh: number):void
Z
zengyawen 已提交
2046

E
ester.zhou 已提交
2047
Draws an image on the canvas.
Z
zengyawen 已提交
2048

E
ester.zhou 已提交
2049
Since API version 9, this API is supported in ArkTS widgets, except that **PixelMap** objects are not supported.
E
ester.zhou 已提交
2050

E
ester.zhou 已提交
2051
**Parameters**
Z
zengyawen 已提交
2052

E
ester.zhou 已提交
2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063
| Name   | Type                                      | Mandatory  | Default Value | Description                                      |
| ----- | ---------------------------------------- | ---- | ---- | ---------------------------------------- |
| image | [ImageBitmap](ts-components-canvas-imagebitmap.md) or [PixelMap](../apis/js-apis-image.md#pixelmap7)| Yes   | null | Image resource. For details, see **ImageBitmap** or PixelMap.           |
| sx    | number                                   | No   | 0    | X-coordinate of the upper left corner of the rectangle used to crop the source image.                    |
| sy    | number                                   | No   | 0    | Y-coordinate of the upper left corner of the rectangle used to crop the source image.                    |
| sw    | number                                   | No   | 0    | Target width to crop the source image.                          |
| sh    | number                                   | No   | 0    | Target height to crop the source image.                          |
| dx    | number                                   | Yes   | 0    | X-coordinate of the upper left corner of the drawing area on the canvas.                          |
| dy    | number                                   | Yes   | 0    | Y-coordinate of the upper left corner of the drawing area on the canvas.                    |
| dw    | number                                   | No   | 0    | Width of the drawing area. If the width of the drawing area is different from that of the cropped image, the latter will be stretched or compressed to the former.|
| dh    | number                                   | No   | 0    | Height of the drawing area. If the height of the drawing area is different from that of the cropped image, the latter will be stretched or compressed to the former.|
Z
zengyawen 已提交
2064 2065


E
ester.zhou 已提交
2066
**Example**
H
HelloCrease 已提交
2067

2068 2069
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2070 2071 2072
  @Entry
  @Component
  struct ImageExample {
E
ester.zhou 已提交
2073 2074 2075
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    private img:ImageBitmap = new ImageBitmap("common/images/example.jpg")
E
ester.zhou 已提交
2076

Z
zengyawen 已提交
2077 2078 2079 2080 2081 2082 2083
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
2084
            this.context.drawImage( this.img,0,0,500,500,0,0,400,200)
Z
zengyawen 已提交
2085
        })
Z
zengyawen 已提交
2086
      }
Z
zengyawen 已提交
2087 2088
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2089
    }
Z
zengyawen 已提交
2090 2091 2092 2093 2094 2095 2096 2097
  }
  ```

  ![en-us_image_0000001212058466](figures/en-us_image_0000001212058466.png)


### createImageData

E
ester.zhou 已提交
2098
createImageData(sw: number, sh: number): ImageData
Z
zengyawen 已提交
2099

E
esterzhou 已提交
2100
Creates an **[ImageData](ts-components-canvas-imagedata.md)** object with the specified dimensions.
Z
zengyawen 已提交
2101

E
ester.zhou 已提交
2102 2103
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2104 2105 2106 2107 2108 2109
**Parameters**

| Name  | Type    | Mandatory  | Default Value  | Description           |
| ---- | ------ | ---- | ---- | ------------- |
| sw   | number | Yes   | 0    | Width of the **ImageData** object.|
| sh   | number | Yes   | 0    | Height of the **ImageData** object.|
Z
zengyawen 已提交
2110 2111


E
ester.zhou 已提交
2112
createImageData(imageData: ImageData): ImageData
Z
zengyawen 已提交
2113

E
esterzhou 已提交
2114
Creates an **[ImageData](ts-components-canvas-imagedata.md)** object.
Z
zengyawen 已提交
2115

E
ester.zhou 已提交
2116 2117
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2118 2119 2120 2121
**Parameters**

| Name       | Type                                      | Mandatory  | Default Value  | Description               |
| --------- | ---------------------------------------- | ---- | ---- | ----------------- |
E
esterzhou 已提交
2122
| imagedata | [ImageData](ts-components-canvas-imagedata.md) | Yes   | null | **ImageData** object with the same width and height copied from the original **ImageData** object.|
E
ester.zhou 已提交
2123 2124 2125 2126 2127

  **Return value**

| Type                                      | Description            |
| ---------------------------------------- | -------------- |
E
esterzhou 已提交
2128
| [ImageData](ts-components-canvas-imagedata.md) | New **ImageData** object.|
E
ester.zhou 已提交
2129

Z
zengyawen 已提交
2130

2131 2132 2133 2134 2135
### getPixelMap

getPixelMap(sx: number, sy: number, sw: number, sh: number): PixelMap

Obtains the **[PixelMap](../apis/js-apis-image.md#pixelmap7)** object created with the pixels within the specified area on the canvas.
E
ester.zhou 已提交
2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150

**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description             |
| ---- | ------ | ---- | ---- | --------------- |
| sx   | number | Yes   | 0    | X-coordinate of the upper left corner of the output area.|
| sy   | number | Yes   | 0    | Y-coordinate of the upper left corner of the output area.|
| sw   | number | Yes   | 0    | Width of the output area.    |
| sh   | number | Yes   | 0    | Height of the output area.    |

**Return value**

| Type                                      | Description           |
| ---------------------------------------- | ------------- |
| [PixelMap](../apis/js-apis-image.md#pixelmap7) | **PixelMap** object.|
Z
zengyawen 已提交
2151 2152 2153

### getImageData

E
ester.zhou 已提交
2154
getImageData(sx: number, sy: number, sw: number, sh: number): ImageData
Z
zengyawen 已提交
2155

E
esterzhou 已提交
2156
Obtains the **[ImageData](ts-components-canvas-imagedata.md)** object created with the pixels within the specified area on the canvas.
E
ester.zhou 已提交
2157

E
ester.zhou 已提交
2158 2159
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description             |
| ---- | ------ | ---- | ---- | --------------- |
| sx   | number | Yes   | 0    | X-coordinate of the upper left corner of the output area.|
| sy   | number | Yes   | 0    | Y-coordinate of the upper left corner of the output area.|
| sw   | number | Yes   | 0    | Width of the output area.    |
| sh   | number | Yes   | 0    | Height of the output area.    |

  **Return value**

| Type                                      | Description            |
| ---------------------------------------- | -------------- |
E
esterzhou 已提交
2173 2174 2175 2176 2177 2178 2179
| [ImageData](ts-components-canvas-imagedata.md) | New **ImageData** object.|


**Example**

  ```ts
  // xxx.ets
E
ester.zhou 已提交
2180 2181 2182 2183 2184 2185
  @Entry
  @Component
  struct GetImageData {
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    private img:ImageBitmap = new ImageBitmap("/common/images/1234.png")
E
esterzhou 已提交
2186

E
ester.zhou 已提交
2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.drawImage(this.img,0,0,130,130)
            var imagedata = this.context.getImageData(50,50,130,130)
            this.context.putImageData(imagedata,150,150)
          })
      }
      .width('100%')
      .height('100%')
E
esterzhou 已提交
2201 2202 2203 2204 2205
    }
  }
  ```

  ![en-us_image_000000127777780](figures/en-us_image_000000127777780.png)
Z
zengyawen 已提交
2206 2207 2208 2209


### putImageData

E
ester.zhou 已提交
2210 2211 2212 2213
putImageData(imageData: ImageData, dx: number, dy: number): void

putImageData(imageData: ImageData, dx: number, dy: number, dirtyX: number, dirtyY: number, dirtyWidth: number, dirtyHeight: number): void

E
esterzhou 已提交
2214
Puts an **[ImageData](ts-components-canvas-imagedata.md)** object onto a rectangular area on the canvas.
Z
zengyawen 已提交
2215

E
ester.zhou 已提交
2216 2217
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2218
**Parameters**
Z
zengyawen 已提交
2219

E
ester.zhou 已提交
2220 2221
| Name         | Type                                      | Mandatory  | Default Value         | Description                           |
| ----------- | ---------------------------------------- | ---- | ------------ | ----------------------------- |
E
esterzhou 已提交
2222
| imagedata   | [ImageData](ts-components-canvas-imagedata.md) | Yes   | null         | **ImageData** object with pixels to put onto the canvas.           |
E
ester.zhou 已提交
2223 2224 2225 2226 2227 2228
| dx          | number                                   | Yes   | 0            | X-axis offset of the rectangular area on the canvas.               |
| dy          | number                                   | Yes   | 0            | Y-axis offset of the rectangular area on the canvas.               |
| dirtyX      | number                                   | No   | 0            | X-axis offset of the upper left corner of the rectangular area relative to that of the source image.|
| dirtyY      | number                                   | No   | 0            | Y-axis offset of the upper left corner of the rectangular area relative to that of the source image.|
| dirtyWidth  | number                                   | No   | Width of the **ImageData** object| Width of the rectangular area to crop the source image.              |
| dirtyHeight | number                                   | No   | Height of the **ImageData** object| Height of the rectangular area to crop the source image.              |
Z
zengyawen 已提交
2229

E
ester.zhou 已提交
2230
**Example**
H
HelloCrease 已提交
2231

2232 2233
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2234 2235 2236
  @Entry
  @Component
  struct PutImageData {
E
ester.zhou 已提交
2237 2238
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
2239

Z
zengyawen 已提交
2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var imageData = this.context.createImageData(100, 100)
            for (var i = 0; i < imageData.data.length; i += 4) {
              imageData.data[i + 0] = 255
              imageData.data[i + 1] = 0
              imageData.data[i + 2] = 255
              imageData.data[i + 3] = 255
            }
            this.context.putImageData(imageData, 10, 10)
          })
Z
zengyawen 已提交
2256
      }
Z
zengyawen 已提交
2257 2258
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2259
    }
Z
zengyawen 已提交
2260 2261
  }
  ```
Z
zengyawen 已提交
2262

Z
zengyawen 已提交
2263
  ![en-us_image_0000001212378396](figures/en-us_image_0000001212378396.png)
Z
zengyawen 已提交
2264 2265


E
ester.zhou 已提交
2266 2267 2268 2269 2270 2271
### setLineDash

setLineDash(segments: number[]): void

Sets the dash line style.

E
ester.zhou 已提交
2272 2273
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298
**Parameters**

| Name      | Type      | Description                 |
| -------- | -------- | ------------------- |
| segments | number[] | An array of numbers that specify distances to alternately draw a line and a gap.|

**Example**

  ```ts
  // xxx.ets
  @Entry
  @Component
  struct SetLineDash {
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            this.context.arc(100, 75, 50, 0, 6.28)
            this.context.setLineDash([10,20])
E
esterzhou 已提交
2299
            this.context.stroke()
E
ester.zhou 已提交
2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316
          })
      }
      .width('100%')
      .height('100%')
    }
  }
  ```

  ![en-us_image_000000127777771](figures/en-us_image_000000127777771.png)


### getLineDash

getLineDash(): number[]

Obtains the dash line style.

E
ester.zhou 已提交
2317 2318
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2319 2320 2321 2322 2323 2324
**Return value**

| Type      | Description                      |
| -------- | ------------------------ |
| number[] | An array of numbers that specify distances to alternately draw a line and a gap.|

E
esterzhou 已提交
2325

E
ester.zhou 已提交
2326 2327 2328 2329
**Example**

  ```ts
  // xxx.ets
E
ester.zhou 已提交
2330 2331 2332 2333 2334 2335
  @Entry
  @Component
  struct CanvasGetLineDash {
    @State message: string = 'Hello World'
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
esterzhou 已提交
2336

E
ester.zhou 已提交
2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359
    build() {
      Row() {
        Column() {
          Text(this.message)
            .fontSize(50)
            .fontWeight(FontWeight.Bold)
            .onClick(()=>{
              console.error('before getlinedash clicked')
              let res = this.context.getLineDash()
              console.error(JSON.stringify(res))
            })
          Canvas(this.context)
            .width('100%')
            .height('100%')
            .backgroundColor('#ffff00')
            .onReady(() => {
              this.context.arc(100, 75, 50, 0, 6.28)
              this.context.setLineDash([10,20])
              this.context.stroke()
              let res = this.context.getLineDash()
            })
        }
        .width('100%')
E
ester.zhou 已提交
2360
      }
E
ester.zhou 已提交
2361
      .height('100%')
E
ester.zhou 已提交
2362 2363 2364
    }
  }
  ```
E
esterzhou 已提交
2365 2366
![en-us_image_000000127777778](figures/en-us_image_000000127777778.png) 

E
ester.zhou 已提交
2367 2368 2369 2370 2371 2372


### imageSmoothingQuality

imageSmoothingQuality(quality: imageSmoothingQuality)

E
esterzhou 已提交
2373
Sets the quality of image smoothing. This API is a void API.
E
ester.zhou 已提交
2374

E
ester.zhou 已提交
2375 2376
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390
 **Parameters**

| Name     | Type                   | Description                                      |
| ------- | --------------------- | ---------------------------------------- |
| quality | imageSmoothingQuality | The options are as follows: '**low'**, **'medium'**, and **'high'**.|



### transferFromImageBitmap

transferFromImageBitmap(bitmap: ImageBitmap): void

Displays the specified **ImageBitmap** object.

E
ester.zhou 已提交
2391 2392
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2393 2394 2395 2396
**Parameters**

| Name    | Type                                      | Description                |
| ------ | ---------------------------------------- | ------------------ |
E
esterzhou 已提交
2397
| bitmap | [ImageBitmap](ts-components-canvas-imagebitmap.md) | **ImageBitmap** object to display.|
E
ester.zhou 已提交
2398 2399 2400 2401 2402 2403 2404

**Example**

  ```ts
  // xxx.ets
  @Entry
  @Component
E
esterzhou 已提交
2405
  struct TransferFromImageBitmap {
E
ester.zhou 已提交
2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
    private offContext: OffscreenCanvasRenderingContext2D = new OffscreenCanvasRenderingContext2D(600, 600, this.settings)

    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var imageData = this.offContext.createImageData(100, 100)
            for (var i = 0; i < imageData.data.length; i += 4) {
              imageData.data[i + 0] = 255
              imageData.data[i + 1] = 0
              imageData.data[i + 2] = 255
              imageData.data[i + 3] = 255
            }
            this.offContext.putImageData(imageData, 10, 10)
            var image = this.offContext.transferToImageBitmap()
            this.context.transferFromImageBitmap(image)
          })
      }
      .width('100%')
      .height('100%')
    }
  }
  ```
  ![en-us_image_000000127777773](figures/en-us_image_000000127777773.png)  

E
esterzhou 已提交
2436

E
ester.zhou 已提交
2437 2438 2439 2440 2441 2442
### toDataURL

toDataURL(type?: string, quality?: number): string

Generates a URL containing image display information.

E
ester.zhou 已提交
2443 2444
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461
**Parameters**

| Name    | Type  | Mandatory  | Description                                      |
| ------- | ------ | ---- | ---------------------------------------- |
| type    | string | No   | Image format. The default value is **image/png**.           |
| quality | number | No   | Image quality, which ranges from 0 to 1, when the image format is **image/jpeg** or **image/webp**. If the set value is beyond the value range, the default value **0.92** is used.|

**Return value**

| Type    | Description       |
| ------ | --------- |
| string | Image URL.|

**Example**

  ```ts
  // xxx.ets
E
ester.zhou 已提交
2462 2463 2464 2465 2466
  @Entry
  @Component
  struct ToDataURL {
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
E
ester.zhou 已提交
2467

E
ester.zhou 已提交
2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var dataURL = this.context.toDataURL()
          })
      }
      .width('100%')
      .height('100%')
E
ester.zhou 已提交
2480 2481 2482 2483 2484
    }
  }
  ```


Z
zengyawen 已提交
2485
### restore
Z
zengyawen 已提交
2486

Z
zengyawen 已提交
2487
restore(): void
Z
zengyawen 已提交
2488 2489 2490

Restores the saved drawing context.

E
ester.zhou 已提交
2491 2492
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2493
**Example**
H
HelloCrease 已提交
2494

2495 2496
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2497 2498 2499
  @Entry
  @Component
  struct CanvasExample {
E
ester.zhou 已提交
2500 2501
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
2502

Z
zengyawen 已提交
2503 2504 2505 2506 2507 2508 2509
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
2510
            this.context.save() // save the default state
E
ester.zhou 已提交
2511
            this.context.fillStyle = "#00ff00"
E
ester.zhou 已提交
2512 2513 2514
            this.context.fillRect(20, 20, 100, 100)
            this.context.restore() // restore to the default state
            this.context.fillRect(150, 75, 100, 100)
Z
zengyawen 已提交
2515
          })
Z
zengyawen 已提交
2516
      }
Z
zengyawen 已提交
2517 2518
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2519
    }
Z
zengyawen 已提交
2520 2521
  }
  ```
E
esterzhou 已提交
2522
  ![en-us_image_000000127777781](figures/en-us_image_000000127777781.png)
Z
zengyawen 已提交
2523 2524


Z
zengyawen 已提交
2525
### save
Z
zengyawen 已提交
2526

Z
zengyawen 已提交
2527
save(): void
Z
zengyawen 已提交
2528

E
ester.zhou 已提交
2529
Saves all states of the canvas in the stack. This API is usually called when the drawing state needs to be saved.
Z
zengyawen 已提交
2530

E
ester.zhou 已提交
2531 2532
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2533
**Example**
H
HelloCrease 已提交
2534

2535 2536
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2537 2538 2539
  @Entry
  @Component
  struct CanvasExample {
E
ester.zhou 已提交
2540 2541
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
H
HelloCrease 已提交
2542

Z
zengyawen 已提交
2543 2544 2545 2546 2547 2548 2549
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
E
ester.zhou 已提交
2550
            this.context.save() // save the default state
E
ester.zhou 已提交
2551
            this.context.fillStyle = "#00ff00"
E
ester.zhou 已提交
2552 2553 2554
            this.context.fillRect(20, 20, 100, 100)
            this.context.restore() // restore to the default state
            this.context.fillRect(150, 75, 100, 100)
E
esterzhou 已提交
2555
          })
Z
zengyawen 已提交
2556
      }
Z
zengyawen 已提交
2557 2558
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2559
    }
Z
zengyawen 已提交
2560 2561
  }
  ```
E
esterzhou 已提交
2562
  ![en-us_image_000000127777781](figures/en-us_image_000000127777781.png)
Z
zengyawen 已提交
2563 2564


Z
zengyawen 已提交
2565
### createLinearGradient
Z
zengyawen 已提交
2566

Z
zengyawen 已提交
2567
createLinearGradient(x0: number, y0: number, x1: number, y1: number): void
Z
zengyawen 已提交
2568 2569 2570

Creates a linear gradient.

E
ester.zhou 已提交
2571 2572
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2573 2574 2575 2576 2577 2578 2579 2580
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description      |
| ---- | ------ | ---- | ---- | -------- |
| x0   | number | Yes   | 0    | X-coordinate of the start point.|
| y0   | number | Yes   | 0    | Y-coordinate of the start point.|
| x1   | number | Yes   | 0    | X-coordinate of the end point.|
| y1   | number | Yes   | 0    | Y-coordinate of the end point.|
Z
zengyawen 已提交
2581

E
ester.zhou 已提交
2582
**Example**
H
HelloCrease 已提交
2583

2584 2585
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2586 2587 2588
  @Entry
  @Component
  struct CreateLinearGradient {
E
ester.zhou 已提交
2589 2590
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
2591
    
Z
zengyawen 已提交
2592 2593 2594 2595 2596 2597 2598 2599
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var grad = this.context.createLinearGradient(50,0, 300,100)
E
ester.zhou 已提交
2600 2601 2602
            grad.addColorStop(0.0, '#ff0000')
            grad.addColorStop(0.5, '#ffffff')
            grad.addColorStop(1.0, '#00ff00')
Z
zengyawen 已提交
2603
            this.context.fillStyle = grad
E
ester.zhou 已提交
2604
            this.context.fillRect(0, 0, 400, 400)
Z
zengyawen 已提交
2605
          })
Z
zengyawen 已提交
2606
      }
Z
zengyawen 已提交
2607 2608
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2609
    }
Z
zengyawen 已提交
2610 2611
  }
  ```
Z
zengyawen 已提交
2612

Z
zengyawen 已提交
2613
  ![en-us_image_0000001212378412](figures/en-us_image_0000001212378412.png)
Z
zengyawen 已提交
2614 2615


Z
zengyawen 已提交
2616
### createRadialGradient
Z
zengyawen 已提交
2617

Z
zengyawen 已提交
2618
createRadialGradient(x0: number, y0: number, r0: number, x1: number, y1: number, r1: number): void
Z
zengyawen 已提交
2619 2620 2621

Creates a linear gradient.

E
ester.zhou 已提交
2622 2623
Since API version 9, this API is supported in ArkTS widgets.

E
ester.zhou 已提交
2624 2625 2626 2627 2628 2629 2630 2631 2632 2633
**Parameters**

| Name  | Type    | Mandatory  | Default Value | Description               |
| ---- | ------ | ---- | ---- | ----------------- |
| x0   | number | Yes   | 0    | X-coordinate of the center of the start circle.        |
| y0   | number | Yes   | 0    | Y-coordinate of the center of the start circle.        |
| r0   | number | Yes   | 0    | Radius of the start circle, which must be a non-negative finite number.|
| x1   | number | Yes   | 0    | X-coordinate of the center of the end circle.        |
| y1   | number | Yes   | 0    | Y-coordinate of the center of the end circle.        |
| r1   | number | Yes   | 0    | Radius of the end circle, which must be a non-negative finite number.|
Z
zengyawen 已提交
2634

E
ester.zhou 已提交
2635
**Example**
H
HelloCrease 已提交
2636

2637 2638
  ```ts
  // xxx.ets
Z
zengyawen 已提交
2639 2640 2641
  @Entry
  @Component
  struct CreateRadialGradient {
E
ester.zhou 已提交
2642 2643
    private settings: RenderingContextSettings = new RenderingContextSettings(true)
    private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)
Z
zengyawen 已提交
2644 2645 2646 2647 2648 2649 2650 2651 2652
    
    build() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .backgroundColor('#ffff00')
          .onReady(() =>{
            var grad = this.context.createRadialGradient(200,200,50, 200,200,200)
E
ester.zhou 已提交
2653 2654 2655
            grad.addColorStop(0.0, '#ff0000')
            grad.addColorStop(0.5, '#ffffff')
            grad.addColorStop(1.0, '#00ff00')
Z
zengyawen 已提交
2656
            this.context.fillStyle = grad
E
ester.zhou 已提交
2657
            this.context.fillRect(0, 0, 440, 440)
Z
zengyawen 已提交
2658
          })
Z
zengyawen 已提交
2659
      }
Z
zengyawen 已提交
2660 2661
      .width('100%')
      .height('100%')
Z
zengyawen 已提交
2662
    }
Z
zengyawen 已提交
2663 2664
  }
  ```
Z
zengyawen 已提交
2665

Z
zengyawen 已提交
2666
  ![en-us_image_0000001257058405](figures/en-us_image_0000001257058405.png)
Z
zengyawen 已提交
2667

E
ester.zhou 已提交
2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713
### createConicGradient<sup>10+</sup>

createConicGradient(startAngle: number, x: number, y: number): CanvasGradient

Creates a conic gradient.

**Parameters**

| Name      | Type  | Mandatory| Default Value| Description                                                        |
| ---------- | ------ | ---- | ------ | ------------------------------------------------------------ |
| startAngle | number | Yes  | 0      | Angle at which the gradient starts, in radians. The angle measurement starts horizontally from the right side of the center and moves clockwise.|
| x          | number | Yes  | 0      | X-coordinate of the center of the conic gradient, in vp.                             |
| y          | number | Yes  | 0      | Y-coordinate of the center of the conic gradient, in vp.                             |

**Example**

```ts
// xxx.ets
@Entry
@Component
struct CanvasExample {
  private settings: RenderingContextSettings = new RenderingContextSettings(true)
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings)

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Canvas(this.context)
        .width('100%')
        .height('100%')
        .backgroundColor('#ffffff')
        .onReady(() => {
          var grad = this.context.createConicGradient(0, 50, 80)
          grad.addColorStop(0.0, '#ff0000')
          grad.addColorStop(0.5, '#ffffff')
          grad.addColorStop(1.0, '#00ff00')
          this.context.fillStyle = grad
          this.context.fillRect(0, 30, 100, 100)
        })
    }
    .width('100%')
    .height('100%')
  }
}
```

  ![en-us_image_0000001239032419](figures/en-us_image_0000001239032420.png)
Z
zengyawen 已提交
2714

Z
zengyawen 已提交
2715
## CanvasPattern
Z
zengyawen 已提交
2716

E
ester.zhou 已提交
2717
Defines an object created using the **[createPattern](#createpattern)** API.
E
ester.zhou 已提交
2718 2719

Since API version 9, this API is supported in ArkTS widgets.