js-apis-animator.md

# @ohos.animator (Animator)

The **Animator** module provides APIs for applying animation effects, including defining animations, starting animations, and playing animations in reverse order.

> **NOTE**
>
> The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.
>
> This module cannot be used in the file declaration of the [UIAbility](./js-apis-app-ability-uiAbility.md). In other words, the APIs of this module can be used only after a component instance is created; they cannot be called in the lifecycle of the UIAbility.
>
> The functionality of this module depends on UI context. This means that the APIs of this module cannot be used where the UI context is unclear. For details, see [UIContext](./js-apis-arkui-UIContext.md#uicontext).
>
> Since API version 10, you can use the [createAnimator](./js-apis-arkui-UIContext.md#createanimator) API in [UIContext](./js-apis-arkui-UIContext.md#uicontext) to obtain the UI context.

## Modules to Import

```js
import animator from '@ohos.animator';
```
## create<sup>9+</sup>

create(options: AnimatorOptions): AnimatorResult

Creates an **Animator** object.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Parameters**

| Name    | Type                                 | Mandatory  | Description     |
| ------- | ----------------------------------- | ---- | ------- |
| options | [AnimatorOptions](#animatoroptions) | Yes   | Animator options.|

**Return value**

| Type                               | Description           |
| --------------------------------- | ------------- |
| [AnimatorResult](#animatorresult) | Animator result.|

**Example**

  ```js
import animator, { AnimatorOptions } from '@ohos.animator';

let options: AnimatorOptions = { // The explicit type AnimatorOptions does not need to be emphasized in the xxx.js file.
  duration: 1500,
  easing: "friction",
  delay: 0,
  fill: "forwards",
  direction: "normal",
  iterations: 3,
  begin: 200.0,
  end: 400.0
};
animator.create(options);
  ```

## AnimatorResult

Defines the animator result.

### reset<sup>9+</sup>

reset(options: AnimatorOptions): void

Updates this animator.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Parameters**

| Name    | Type                                 | Mandatory  | Description     |
| ------- | ----------------------------------- | ---- | ------- |
| options | [AnimatorOptions](#animatoroptions) | Yes   | Animator options.|

**Error codes**

For details about the error codes, see [Animator Error Codes](../errorcodes/errorcode-animator.md).

| ID  | Error Message|
| --------- | ------- |
| 100001    | if no page is found for pageId or fail to get object property list. |


**Example**

```js
let options: AnimatorOptions = { // The explicit type AnimatorOptions does not need to be emphasized in the xxx.js file.
  duration: 1500,
  easing: "friction",
  delay: 0,
  fill: "forwards",
  direction: "normal",
  iterations: 3,
  begin: 200.0,
  end: 400.0
};
try {
  animator.reset(options);
} catch(error) {
  console.error(`Animator reset failed, error code: ${error.code}, message: ${error.message}.`);
}
```

### play

play(): void

Plays this animation. The animation retains the previous playback state. For example, if the animation is set to **reverse** and paused, it will remain in **reverse** when resumed.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
animator.play();
```

### finish

finish(): void

Ends this animation.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
animator.finish();
```

### pause

pause(): void

Pauses this animation.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
animator.pause();
```

### cancel

cancel(): void

Cancels this animation.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
animator.cancel();
```

### reverse

reverse(): void

Plays this animation in reverse order.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
animator.reverse();
```

### onframe

onframe: (progress: number) => void

Called when a frame is received.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Parameters**

| Name     | Type    | Mandatory  | Description      |
| -------- | ------ | ---- | -------- |
| progress | number | Yes   | Current progress of the animation.|

**Example**

```js
let animatorResult = animator.create(options)
animatorResult.onframe = function(value) {
  console.info("onframe callback")
}
```

### onfinish

onfinish: () => void

Called when this animation is finished.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
let animatorResult = animator.create(options)
animatorResult.onfinish = function() {
  console.info("onfinish callback")
}
```

### oncancel

oncancel: () => void

Called when this animation is canceled.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
let animatorResult = animator.create(options)
animatorResult.oncancel = function() {
  console.info("oncancel callback")
}
```

### onrepeat

onrepeat: () => void

Called when this animation repeats.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Example**

```js
let animatorResult = animator.create(options)
animatorResult.onrepeat = function() {
  console.info("onrepeat callback")
}
```



## AnimatorOptions

Defines animator options.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

| Name      | Type                                                       | Mandatory| Description                                                        |
| ---------- | ----------------------------------------------------------- | ---- | ------------------------------------------------------------ |
| duration   | number                                                      | Yes  | Duration for playing the animation, in milliseconds.                                  |
| easing     | string                                                      | Yes  | Animation interpolation curve. Only the following values are supported:<br>**"linear"**: The animation speed keeps unchanged.<br>**"ease"**: The animation starts slowly, accelerates, and then slows down towards the end. The cubic-bezier curve (0.25, 0.1, 0.25, 1.0) is used.<br>**"ease-in"**: The animation starts at a low speed and then picks up speed until the end. The cubic-bezier curve (0.42, 0.0, 1.0, 1.0) is used.<br>**"ease-out"**: The animation ends at a low speed. The cubic-bezier curve (0.0, 0.0, 0.58, 1.0) is used.<br>**"ease-in-out"**: The animation starts and ends at a low speed. The cubic-bezier curve (0.42, 0.0, 0.58, 1.0) is used.<br>**"fast-out-slow-in"**: The animation uses the standard cubic-bezier curve (0.4, 0.0, 0.2, 1.0).<br>**"linear-out-slow-in"**: The animation uses the deceleration cubic-bezier curve (0.0, 0.0, 0.2, 1.0).<br>**"friction"**: The animation uses the damping cubic-bezier curve (0.2, 0.0, 0.2, 1.0).<br>**"extreme-deceleration"**: The animation uses the extreme deceleration cubic-bezier curve (0.0, 0.0, 0.0, 1.0).<br>**"rhythm"**: The animation uses the rhythm cubic-bezier curve (0.7, 0.0, 0.2, 1.0).<br>**"sharp"**: The animation uses the sharp cubic-bezier curve (0.33, 0.0, 0.67, 1.0).<br>**"smooth"**: The animation uses the smooth cubic-bezier curve (0.4, 0.0, 0.4, 1.0).<br>**"cubic-bezier(x1,y1,x2,y2)"**: The animation uses the defined cubic bezier curve, where the value of **x1** and **x2** must range from 0 to 1. For example, **"cubic-bezier(0.42,0.0,0.58,1.0)"**.<br>**"steps(number,step-position)"**: The animation uses a step curve. The **number** parameter is mandatory and must be set to a positive integer. The **step-position** parameter is optional and can be set to **start** or **end** (default value). For example, **"steps(3,start)"**.|
| delay      | number                                                      | Yes  | Animation delay duration, in milliseconds. Value **0** means that there is no delay.         |
| fill       | "none" \| "forwards" \| "backwards" \| "both"               | Yes  | State of the animated target after the animation is executed.<br>**"none"**: No style is applied to the target before or after the animation is executed.<br>**"forwards"**: The target keeps the state at the end of the animation (defined in the last key frame) after the animation is executed.<br>**"backwards"**: The animation uses the value defined in the first key frame during the **animation-delay**. When **animation-direction** is set to **normal** or **alternate**, the value in the **from** key frame is used. When **animation-direction** is set to **reverse** or **alternate-reverse**, the value in the **to** key frame is used.<br>**"both"**: The animation follows the **forwards** and **backwards** rules.|
| direction  | "normal" \| "reverse" \| "alternate" \| "alternate-reverse" | Yes  | Animation playback mode.<br>**"normal"**: plays the animation in forward loop mode.<br>**"reverse"**: plays the animation in reverse loop mode.<br>**"alternate"**: plays the animation in alternating loop mode. When the animation is played for an odd number of times, the playback is in forward direction. When the animation is played for an even number of times, the playback is in reverse direction.<br>**"alternate-reverse"**: plays the animation in reverse alternating loop mode. When the animation is played for an odd number of times, the playback is in reverse direction. When the animation is played for an even number of times, the playback is in forward direction.|
| iterations | number                                                      | Yes  | Number of times that the animation is played. The value **0** means not to play the animation, and **-1** means to play the animation for an unlimited number of times.<br>**NOTE**<br>If this parameter is set to a negative value other than **-1**, the value is invalid. In this case, the animation is played once.|
| begin      | number                                                      | Yes  | Start point of the animation interpolation.                                              |
| end        | number                                                      | Yes  | End point of animation interpolation.                                              |


## Example
### JavaScript-compatible Web-like Development Paradigm

```html
<!-- hml -->
<div class="container">
  <div class="Animation" style="height: {{divHeight}}px; width: {{divWidth}}px; background-color: red;" onclick="Show">
  </div>
</div>
```

```js
export default {
  data: {
    divWidth: 200,
    divHeight: 200,
    animator: null
  },
  onInit() {
    let options = {
      duration: 1500,
      easing: "friction",
      delay: 0,
      fill: "forwards",
      direction: "normal",
      iterations: 2,
      begin: 200.0,
      end: 400.0
    };
    this.animator = animator.create(options);
  },
  Show() {
    let options1 = {
      duration: 1500,
      easing: "friction",
      delay: 0,
      fill: "forwards",
      direction: "normal",
      iterations: 2,
      begin: 0,
      end: 400.0,
    };
    try {
      this.animator.reset(options1);
    } catch(error) {
      console.error(`Animator reset failed, error code: ${error.code}, message: ${error.message}.`);
    }
    let _this = this;
    this.animator.onframe = function(value) {
      _this.divWidth = value;
      _this.divHeight = value;
    };
    this.animator.play();
  }
}
```

  ![en-us_image_00007](figures/en-us_image_00007.gif)

### ArkTS-based Declarative Development Paradigm

```ts
import animator from '@ohos.animator';

@Entry
@Component
struct AnimatorTest {
  private TAG: string = '[AnimatorTest]'
  private backAnimator: any = undefined
  private flag: boolean = false
  @State wid: number = 100
  @State hei: number = 100

  create() {
    let _this = this
    this.backAnimator = animator.create({
      duration: 2000,
      easing: "ease",
      delay: 0,
      fill: "none",
      direction: "normal",
      iterations: 1,
      begin: 100,
      end: 200
    })
    this.backAnimator.onfinish = function () {
      _this.flag = true
      console.info(_this.TAG, 'backAnimator onfinish')
    }
    this.backAnimator.onrepeat = function () {
      console.info(_this.TAG, 'backAnimator repeat')
    }
    this.backAnimator.oncancel = function () {
      console.info(_this.TAG, 'backAnimator cancel')
    }
    this.backAnimator.onframe = function (value) {
      _this.wid = value
      _this.hei = value
    }
  }

  build() {
    Column() {
      Column() {
        Column()
          .width(this.wid)
          .height(this.hei)
          .backgroundColor(Color.Red)
      }
      .width('100%')
      .height(300)

      Column() {
        Row() {
          Button('create')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.create()
            })
        }
        .padding(10)

        Row() {
          Button('play')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.flag = false
              this.backAnimator.play()
            })
        }
        .padding(10)

        Row() {
          Button('pause')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.backAnimator.pause()
            })
        }
        .padding(10)

        Row() {
          Button('finish')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.flag = true
              this.backAnimator.finish()
            })
        }
        .padding(10)

        Row() {
          Button('reverse')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.flag = false
              this.backAnimator.reverse()
            })
        }
        .padding(10)

        Row() {
          Button('cancel')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              this.backAnimator.cancel()
            })
        }
        .padding(10)

        Row() {
          Button('reset')
            .fontSize(30)
            .fontColor(Color.Black)
            .onClick(() => {
              if (this.flag) {
                this.flag = false
                this.backAnimator.reset({
                  duration: 5000,
                  easing: "ease-in",
                  delay: 0,
                  fill: "none",
                  direction: "normal",
                  iterations: 4,
                  begin: 100,
                  end: 300
                })
              } else {
                console.info(this.TAG, 'Animation not ended')
              }
            })
        }
        .padding(10)
      }
    }
  }
}
```

## update<sup>(deprecated)</sup>

update(options: AnimatorOptions): void

Updates this animator.

This API is deprecated since API version 9. You are advised to use [reset<sup>9+</sup>](#reset9) instead.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Parameters**

| Name    | Type                                 | Mandatory  | Description     |
| ------- | ----------------------------------- | ---- | ------- |
| options | [AnimatorOptions](#animatoroptions) | Yes   | Animator options.|

**Example**

```js
animator.update(options);
```

## createAnimator<sup>(deprecated)</sup>

createAnimator(options: AnimatorOptions): AnimatorResult

Creates an **Animator** object.

This API is deprecated since API version 9. You are advised to use [create<sup>9+</sup>](#create9) instead.

**System capability**: SystemCapability.ArkUI.ArkUI.Full

**Parameters**

| Name    | Type                                 | Mandatory  | Description     |
| ------- | ----------------------------------- | ---- | ------- |
| options | [AnimatorOptions](#animatoroptions) | Yes   | Animator options.|

**Return value**

| Type                               | Description           |
| --------------------------------- | ------------- |
| [AnimatorResult](#animatorresult) | Animator result.|

**Example**

```js
let options: AnimatorOptions = { // The explicit type AnimatorOptions does not need to be emphasized in the xxx.js file.
  duration: 1500,
  easing: "friction",
  delay: 0,
  fill: "forwards",
  direction: "normal",
  iterations: 3,
  begin: 200.0,
  end: 400.0,
};
this.animator = animator.createAnimator(options);
```