ts-components-canvas-canvasgradient.md 1.7 KB
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# CanvasGradient
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**CanvasGradient** provides a canvas gradient object.
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>  **NOTE**
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>  The APIs of this module are supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.
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## addColorStop
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addColorStop(offset: number, color: string): void
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Adds a color stop for the **CanvasGradient** object based on the specified offset and gradient color.
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- Parameters
  | Name    | Type    | Mandatory  | Default Value      | Description                          |
  | ------ | ------ | ---- | --------- | ---------------------------- |
  | offset | number | Yes   | 0         | Relative position of the gradient stop along the gradient vector. The value ranges from 0 to 1.|
  | color  | string | Yes   | '#ffffff' | Gradient color to set.                    |

- Example

  ```ts
  // xxx.ets
  @Entry
  @Component
  struct Page45 {
    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(() =>{
            var grad = this.context.createLinearGradient(50,0, 300,100)
            grad.addColorStop(0.0, 'red')
            grad.addColorStop(0.5, 'white')
            grad.addColorStop(1.0, 'green')
            this.context.fillStyle = grad
            this.context.fillRect(0, 0, 500, 500)
          })
      }
      .width('100%')
      .height('100%')
    }}
  ```




  ![en-us_image_0000001256858381](figures/en-us_image_0000001256858381.png)