HarmonyOS API：手势处理

// 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.Left | PanDirection.Right })

  build() {
    Column() {
      Column() {
        Text('PanGesture offset:\nX: ' + this.offsetX + '\n' + 'Y: ' + this.offsetY)
      }
      .height(200)
      .width(300)
      .padding(20)
      .border({ width: 3 })
      .margin(50)
      .translate({ x: this.offsetX, y: this.offsetY, z: 0 })
      // 左右拖动触发该手势事件
      .gesture(
      PanGesture(this.panOption)
        .onActionStart((event: GestureEvent) => {
          console.info('Pan start')
        })
        .onActionUpdate((event: GestureEvent) => {
          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')
        })
      )

      Button('修改PanGesture触发条件')
        .onClick(() => {
          // 将PanGesture手势事件触发条件改为双指以任意方向拖动
          this.panOption.setDirection(PanDirection.All)
          this.panOption.setFingers(2)
        })
    }
  }
}

// xxx.ets
@Entry
@Component
struct PinchGestureExample {
  @State scaleValue: number = 1
  @State pinchValue: number = 1
  @State pinchX: number = 0
  @State pinchY: number = 0

  build() {
    Column() {
      Column() {
        Text('PinchGesture scale:\n' + this.scaleValue)
        Text('PinchGesture center:\n(' + this.pinchX + ',' + this.pinchY + ')')
      }
      .height(200)
      .width(300)
      .padding(20)
      .border({ width: 3 })
      .margin({ top: 100 })
      .scale({ x: this.scaleValue, y: this.scaleValue, z: 1 })
      // 三指捏合触发该手势事件
      .gesture(
      PinchGesture({ fingers: 3 })
        .onActionStart((event: GestureEvent) => {
          console.info('Pinch start')
        })
        .onActionUpdate((event: GestureEvent) => {
          this.scaleValue = this.pinchValue * event.scale
          this.pinchX = event.pinchCenterX
          this.pinchY = event.pinchCenterY
        })
        .onActionEnd(() => {
          this.pinchValue = this.scaleValue
          console.info('Pinch end')
        })
      )
    }.width('100%')
  }
}

// xxx.ets
@Entry
@Component
struct RotationGestureExample {
  @State angle: number = 0
  @State rotateValue: number = 0

  build() {
    Column() {
      Column() {
        Text('RotationGesture angle:' + this.angle)
      }
      .height(200)
      .width(300)
      .padding(20)
      .border({ width: 3 })
      .margin(80)
      .rotate({ angle: this.angle })
      // 双指旋转触发该手势事件
      .gesture(
      RotationGesture()
        .onActionStart((event: GestureEvent) => {
          console.info('Rotation start')
        })
        .onActionUpdate((event: GestureEvent) => {
          this.angle = this.rotateValue + event.angle
        })
        .onActionEnd(() => {
          this.rotateValue = this.angle
          console.info('Rotation end')
        })
      )
    }.width('100%')
  }
}

// xxx.ets
@Entry
@Component
struct SwipeGestureExample {
  @State rotateAngle: number = 0
  @State speed: number = 1

  build() {
    Column() {
      Column() {
        Text("SwipeGesture speed\n" + this.speed)
        Text("SwipeGesture angle\n" + this.rotateAngle)
      }
      .border({ width: 3 })
      .width(300)
      .height(200)
      .margin(100)
      .rotate({ angle: this.rotateAngle })
      // 单指竖直方向滑动时触发该事件
      .gesture(
      SwipeGesture({ direction: SwipeDirection.Vertical })
        .onAction((event: GestureEvent) => {
          this.speed = event.speed
          this.rotateAngle = event.angle
        })
      )
    }.width('100%')
  }
}

// xxx.ets
@Entry
@Component
struct GestureGroupExample {
  @State count: number = 0
  @State offsetX: number = 0
  @State offsetY: number = 0
  @State positionX: number = 0
  @State positionY: number = 0
  @State borderStyles: BorderStyle = BorderStyle.Solid

  build() {
    Column() {
      Text('sequence gesture\n' + 'LongPress onAction:' + this.count + '\nPanGesture offset:\nX: ' + this.offsetX + '\n' + 'Y: ' + this.offsetY)
    }
    .translate({ x: this.offsetX, y: this.offsetY, z: 0 })
    .height(150)
    .width(200)
    .padding(20)
    .margin(20)
    .border({ width: 3, style: this.borderStyles })
    .gesture(
      // 以下组合手势为顺序识别，当长按手势事件未正常触发时则不会触发拖动手势事件
    GestureGroup(GestureMode.Sequence,
    LongPressGesture({ repeat: true })
      .onAction((event: GestureEvent) => {
        if (event.repeat) {
          this.count++
        }
        console.info('LongPress onAction')
      })
      .onActionEnd(() => {
        console.info('LongPress end')
      }),
    PanGesture()
      .onActionStart(() => {
        this.borderStyles = BorderStyle.Dashed
        console.info('pan start')
      })
      .onActionUpdate((event: GestureEvent) => {
        this.offsetX = this.positionX + event.offsetX
        this.offsetY = this.positionY + event.offsetY
        console.info('pan update')
      })
      .onActionEnd(() => {
        this.positionX = this.offsetX
        this.positionY = this.offsetY
        this.borderStyles = BorderStyle.Solid
        console.info('pan end')
      })
    )
      .onCancel(() => {
        console.info('sequence gesture canceled')
      })
    )
  }
}