panGesture结合动画实现fling效果

// xxx.ets 
@Entry 
@Component 
struct PanGestureExample { 
  @State offsetX: number = 0 
  @State offsetY: number = 0 
  @State positionX: number = 0 
  @State positionY: number = 0 
  private panOption: PanGestureOptions = new PanGestureOptions({ direction: PanDirection.Up | PanDirection.Down }) 
  
  build() { 
    Column() { 
        Text('PanGesture offset:\nX: ' + this.offsetX + '\n' + 'Y: ' + this.offsetY) 
      } 
      .height(300) 
      .width(300) 
      .padding(20) 
      .border({ width: 3 }) 
      .margin(50) 
      .translate({ x: this.offsetX, y: this.offsetY, z: 0 }) // 以组件左上角为坐标原点进行移动 
      // 上下拖动触发该手势事件 
      .gesture( 
        PanGesture(this.panOption) 
          .onActionStart((event?: GestureEvent) => { 
            console.info('Pan start') 
          }) 
          .onActionUpdate((event?: GestureEvent) => { 
            if (event) { 
              // this.offsetX = this.positionX + event.offsetX 
              // this.offsetY = this.positionY + event.offsetY 
              console.log('yeyouzhi offsetY>>>'+event.offsetY) 
              animateTo({ 
                duration: 2000, 
                curve: Curve.EaseOut, 
                iterations: 1 , 
                playMode: PlayMode.Normal, 
                onFinish: () => { 
                  console.info('play end') 
                } 
              }, () => { 
  
                this.offsetX = this.positionX + event.offsetX 
                this.offsetY = this.positionY + event.offsetY 
              }) 
            } 
          }) 
          .onActionEnd(() => { 
            this.positionX = this.offsetX 
            this.positionY = this.offsetY 
            console.info('Pan end') 
          }) 
      ) 
  
    } 
  
}