HarmonyOS 如何实现list滑动编辑？

Question

如题：HarmonyOS 如何实现list滑动编辑？

Answer 1

参考下述demo：

@Entry
@Component
struct GridDemo {
  @State numbers: string[] = []
  scroller: Scroller = new Scroller()
  @State text: string = 'drag'
  @State currentIndex: number = -1
  @State x: number = 0
  @State y: number = 0
  @State itemWidth: number = 0

  @Builder
  pixelMapBuilder() { //拖拽过程样式
    Column() {
      Text(this.text)
        .fontSize(16)
        .backgroundColor(0xF9CF93)
        .width(this.itemWidth)
        .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
    let temp: string;
    temp = this.numbers[index1];
    this.numbers[index1] = this.numbers[index2];
    this.numbers[index2] = temp;
  }

  setCurrentIndex(index: number) {
    if (index === this.numbers.length) return
    this.x = this.scroller.getItemRect(index).x
    this.y = this.scroller.getItemRect(index).y
    console.log('this.x', this.x)
    console.log('this.y', this.y)
    this.currentIndex = index
  }

  build() {
    Column({ space: 5 }) {
      Column() {
        Column()
          .width(this.itemWidth)
          .height(80)
          .position({ x: this.x, y: this.y })
          .zIndex(2)
          .visibility(this.currentIndex === -1 ? Visibility.Hidden : Visibility.Visible)
          .border({
            width: 2,
            style: {
              left: BorderStyle.Dotted,
              right: BorderStyle.Dotted,
              top: BorderStyle.Dotted,
              bottom: BorderStyle.Dotted
            }, color: Color.Gray
          })
          .hitTestBehavior(HitTestMode.None)
        Grid(this.scroller) {
          ForEach(this.numbers, (day: string, index: number) => {
            GridItem() {
              Text(day)
                .fontSize(16)
                .backgroundColor(0xF9CF93)
                .width('100%')
                .height(80)
                .textAlign(TextAlign.Center)
            }
          })
        }
        .columnsTemplate('1fr 1fr')
        .columnsGap(10)
        .rowsGap(10)
        .onScrollIndex((first: number) => {
          console.info(first.toString())
        })
        .width('90%')
        .backgroundColor(0xFAEEE0)
        .supportAnimation(true)
        // .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。
          this.text = this.numbers[itemIndex]
          this.itemWidth = this.scroller.getItemRect(itemIndex).width
          this.setCurrentIndex(itemIndex)
          return this.pixelMapBuilder() //设置拖拽过程中显示的图片。
        })
        .onItemDragMove((event: ItemDragInfo, itemIndex: number, insertIndex: number) => {
          this.setCurrentIndex(insertIndex)
        })
        .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('beixiang' + itemIndex + '', insertIndex + '') //itemIndex拖拽起始位置，insertIndex拖拽插入位置
          this.currentIndex = -1
          this.changeIndex(itemIndex, insertIndex)
        })
      }
    }.width('100%').margin({ top: 5 })
  }
}