HarmonyOS 如何在长图展示时加入滑动手势？

@Entry  
@Component  
struct Index {  
  @State offsetX: number = 0  
  @State offsetY: number = 0  
  @State positionX: number = 0  
  @State positionY: number = 0  
  private panOption: PanGestureOptions = new PanGestureOptions({ direction: PanDirection.All })  
  @State vX: number = 0  
  @State vY: number = 0  
  
  build() {  
    Column() {  
      Text('PanGesture offset:\nX: ' + this.offsetX + '\n' + 'Y: ' + this.offsetY)  
      Text('PanGesture speed:\nVX: ' + this.vX + '\n' + 'VY: ' + this.vY)  
    }  
    .height(150)  
    .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  
    .gesture(  
      PanGesture(this.panOption)  
        .onActionStart((event?: GestureEvent) => {  
          console.info('Pan start')  
        })  
        .onActionUpdate((event: GestureEvent) => {  
          animateTo({  
            duration: 0,  
            curve: Curve.EaseOut,  
            iterations: 1,  
            playMode: PlayMode.Normal,  
          }, () => {  
          })  
          if (event) {  
            this.offsetX = this.positionX + event.offsetX  
            this.offsetY = this.positionY + event.offsetY  
            console.info('Pan Update')  
          }  
        })  
        .onActionEnd((event: GestureEvent) => {  
          this.vX = event.velocityX  
          this.vY = event.velocityY  
          if (Math.abs(this.vX) < 50 && Math.abs(this.vY) < 50) {  
            this.positionX = this.offsetX  
            this.positionY = this.offsetY  
            return  
          }  
          animateTo({  
            duration: 1000,  
            curve: Curve.EaseOut,  
            iterations: 1,  
            playMode: PlayMode.Normal,  
          }, () => {  
            this.offsetX = this.positionX + this.vX / 2  
            this.offsetY = this.positionY + this.vY / 2  
            this.positionX = this.offsetX  
            this.positionY = this.offsetY  
          })  
          console.info('Pan end')  
        })  
    )  
  }  
}