HarmonyOS Grid 长按拖动 是否支持部分内容不支持拖动,部分支持？

Question

Grid 长按拖动 是否支持部分内容不支持拖动,部分支持

Answer 1

根据描述可以参考下面代码，代码中0-8不可交换也不可拖动：

@Entry
@Component
struct GridExample {
  @State numbers: string[] = []
  scroller: Scroller = new Scroller()
  @State text: string = 'drag'

  @Builder pixelMapBuilder() { //拖拽过程样式
    Column() {
      Text(this.text)
        .fontSize(16)
        .backgroundColor(0xF9CF93)
        .width(80)
        .height(80)
        .textAlign(TextAlign.Center)
    }
  }

  aboutToAppear() {
    for (let i = 1;i <= 15; i++) {
      this.numbers.push(i + '')
    }
  }

  changeIndex(index1: number, index2: number) { //交换数组位置
    if(index2 <= 8){//不运行与0-8的元素交换位置
      return
    }
    let temp: string;
    temp = this.numbers[index1];
    this.numbers[index1] = this.numbers[index2];
    this.numbers[index2] = temp;
  }

  build() {
    Column({ space: 5 }) {
      Grid(this.scroller) {
        ForEach(this.numbers, (day: string) => {
          GridItem() {
            Text(day)
              .fontSize(16)
              .backgroundColor(0xF9CF93)
              .width(80)
              .height(80)
              .textAlign(TextAlign.Center)
          }
        })
      }
      .columnsTemplate('1fr 1fr 1fr')
      .columnsGap(10)
      .rowsGap(10)
      .width('90%')
      .backgroundColor(0xFAEEE0)
      .height(300)
      .editMode(true) //设置Grid是否进入编辑模式，进入编辑模式可以拖拽Grid组件内部GridItem
      .onItemDragStart((event: ItemDragInfo, itemIndex: number) => { //第一次拖拽此事件绑定的组件时，触发回调。
        if (itemIndex <= 8) {//index 0-8的元素不允许拖动
          return
        }
        this.text = this.numbers[itemIndex]
        return this.pixelMapBuilder() //设置拖拽过程中显示的图片。
      })
      .onItemDrop((event: ItemDragInfo, itemIndex: number, insertIndex: number, isSuccess: boolean) => { //绑定此事件的组件可作为拖拽释放目标，当在本组件范围内停止拖拽行为时，触发回调。
        // isSuccess=false时，说明drop的位置在grid外部；insertIndex > length时，说明有新增元素的事件发生
        if (!isSuccess || insertIndex >= this.numbers.length) {
          return
        }
        console.info('tag' + itemIndex + '', insertIndex + '') //itemIndex拖拽起始位置，insertIndex拖拽插入位置

        this.changeIndex(itemIndex, insertIndex)
      })
    }.width('100%').margin({ top: 5 })
  }
}

如下demo，其中，前面两个item是固定的

import curves from '@ohos.curves'
// xxx.ets
@Entry
@Component
struct GridItemExample {
  @State numbers: number[] = []
  @State dragItem: number = -1
  @State scaleItem: number = -1
  @State item: number = -1
  private dragRefOffsetx: number = 0
  private dragRefOffsety: number = 0
  @State offsetX: number = 0
  @State offsetY: number = 0
  private FIX_VP_X: number = 108
  private FIX_VP_Y: number = 120
  aboutToAppear() {
    for (let i = 1; i <= 11; i++) {
      this.numbers.push(i)
    }
  }
  itemMove(index: number, newIndex: number): void {
    console.info('index:' + index + ' newIndex:' + newIndex)
    if (!this.isDraggable(newIndex)) {
      return
    }
    let tmp = this.numbers.splice(index, 1)
    this.numbers.splice(newIndex, 0, tmp[0])
  }
  //向下滑
  down(index: number): void {
    // 指定固定GridItem不响应事件
    if (!this.isDraggable(index + 3)) {
      return
    }
    this.offsetY -= this.FIX_VP_Y
    this.dragRefOffsety += this.FIX_VP_Y
    this.itemMove(index, index + 3)
  }
  //向下滑(右下角为空)
  down2(index: number): void {
    if (!this.isDraggable(index + 3)) {
      return
    }
    this.offsetY -= this.FIX_VP_Y
    this.dragRefOffsety += this.FIX_VP_Y
    this.itemMove(index, index + 3)
  }
  //向上滑
  up(index: number): void {
    if (!this.isDraggable(index - 3)) {
      return
    }
    this.offsetY += this.FIX_VP_Y
    this.dragRefOffsety -= this.FIX_VP_Y
    this.itemMove(index, index - 3)
  }
  //向左滑
  left(index: number): void {
    if (!this.isDraggable(index - 1)) {
      return
    }
    this.offsetX += this.FIX_VP_X
    this.dragRefOffsetx -= this.FIX_VP_X
    this.itemMove(index, index - 1)
  }
  //向右滑
  right(index: number): void {
    if (!this.isDraggable(index + 1)) {
      return
    }
    this.offsetX -= this.FIX_VP_X
    this.dragRefOffsetx += this.FIX_VP_X
    this.itemMove(index, index + 1)
  }
  //向右下滑
  lowerRight(index: number): void {
    if (!this.isDraggable(index + 4)) {
      return
    }
    this.offsetX -= this.FIX_VP_X
    this.dragRefOffsetx += this.FIX_VP_X
    this.offsetY -= this.FIX_VP_Y
    this.dragRefOffsety += this.FIX_VP_Y
    this.itemMove(index, index + 4)
  }
  //向右上滑
  upperRight(index: number): void {
    if (!this.isDraggable(index - 2)) {
      return
    }
    this.offsetX -= this.FIX_VP_X
    this.dragRefOffsetx += this.FIX_VP_X
    this.offsetY += this.FIX_VP_Y
    this.dragRefOffsety -= this.FIX_VP_Y
    this.itemMove(index, index - 2)
  }
  //向左下滑
  lowerLeft(index: number): void {
    if (!this.isDraggable(index + 2)) {
      return
    }
    this.offsetX += this.FIX_VP_X
    this.dragRefOffsetx -= this.FIX_VP_X
    this.offsetY -= this.FIX_VP_Y
    this.dragRefOffsety += this.FIX_VP_Y
    this.itemMove(index, index + 2)
  }
  //向左上滑
  upperLeft(index: number): void {
    if (!this.isDraggable(index - 4)) {
      return
    }
    this.offsetX += this.FIX_VP_X
    this.dragRefOffsetx -= this.FIX_VP_X
    this.offsetY += this.FIX_VP_Y
    this.dragRefOffsety -= this.FIX_VP_Y
    this.itemMove(index, index - 4)
  }
  isDraggable(index: number): boolean {
    console.info('index:' + index)
    return index > 1
  }
  build() {
    Column() {
      Grid() {
        ForEach(this.numbers, (item: number) => {
          GridItem() {
            Text(item + '')
              .fontSize(16)
              .width('100%')
              .textAlign(TextAlign.Center)
              .height(100)
              .borderRadius(10)
              .backgroundColor(0xFFFFFF)
              .shadow(this.scaleItem == item ? {
                radius: 70,
                color: '#15000000',
                offsetX: 0,
                offsetY: 0
              } :
                {
                  radius: 0,
                  color: '#15000000',
                  offsetX: 0,
                  offsetY: 0
                })
              .animation({ curve: Curve.Sharp, duration: 300 })
          }
          // 指定固定GridItem不响应事件
          .hitTestBehavior(this.isDraggable(this.numbers.indexOf(item)) ? HitTestMode.Default : HitTestMode.None)
          .scale({ x: this.scaleItem == item ? 1.05 : 1, y: this.scaleItem == item ? 1.05 : 1 })
          .zIndex(this.dragItem == item ? 1 : 0)
          .translate(this.dragItem == item ? { x: this.offsetX, y: this.offsetY } : { x: 0, y: 0 })
          .padding(10)
          .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) => {
                  animateTo({ curve: Curve.Friction, duration: 300 }, () => {
                    this.scaleItem = item
                  })
                })
                .onActionEnd(() => {
                  animateTo({ curve: Curve.Friction, duration: 300 }, () => {
                    this.scaleItem = -1
                  })
                }),
              PanGesture({ fingers: 1, direction: null, distance: 0 })
                .onActionStart(() => {
                  this.dragItem = item
                  this.dragRefOffsetx = 0
                  this.dragRefOffsety = 0
                })
                .onActionUpdate((event: GestureEvent) => {
                  this.offsetY = event.offsetY - this.dragRefOffsety
                  this.offsetX = event.offsetX - this.dragRefOffsetx
                  // console.log('X:' + this.offsetX.toString())
                  // console.log('Y:' + this.offsetY.toString())
                  animateTo({ curve: curves.interpolatingSpring(0, 1, 400, 38) }, () => {
                    let index = this.numbers.indexOf(this.dragItem)
                    if (this.offsetY >= this.FIX_VP_Y / 2 && (this.offsetX <= 44 && this.offsetX >= -44)
                      && ![8, 9, 10].includes(index)) {
                      //向下滑
                      this.down(index)
                    } else if (this.offsetY <= -this.FIX_VP_Y / 2 && (this.offsetX <= 44 && this.offsetX >= -44)
                      && ![0, 1, 2].includes(index)) {
                      //向上滑
                      this.up(index)
                    } else if (this.offsetX >= this.FIX_VP_X / 2 && (this.offsetY <= 50 && this.offsetY >= -50)
                      && ![2, 5, 8, 10].includes(index)) {
                      //向右滑
                      this.right(index)
                    } else if (this.offsetX <= -this.FIX_VP_X / 2 && (this.offsetY <= 50 && this.offsetY >= -50)
                      && ![0, 3, 6, 9].includes(index)) {
                      //向左滑
                      this.left(index)
                    } else if (this.offsetX >= this.FIX_VP_X / 2 && this.offsetY >= this.FIX_VP_Y / 2
                      && ![2, 5, 7, 8, 9, 10].includes(index)) {
                      //向右下滑
                      this.lowerRight(index)
                    } else if (this.offsetX >= this.FIX_VP_X / 2 && this.offsetY <= -this.FIX_VP_Y / 2
                      && ![0, 1, 2, 5, 8].includes(index)) {
                      //向右上滑
                      this.upperRight(index)
                    } else if (this.offsetX <= -t