WaterFlow组件如何实现拖拽交换功能

// 导入必要的模块
import {
  Component,
  DragEvent,
  DragEventInfo,
  WaterFlow,
  Column,
  Text,
  DragFlag,
  DragState,
  ForEach,
  state
} from '@ohos/ui-components';

@Component
struct WaterFlowDragSwap {
  @state items: string[] = ['Item 1', 'Item 2', 'Item 3', 'Item 4'];
  @state draggedIndex: number = -1;

  onDragStart(event: DragEventInfo, index: number) {
    this.draggedIndex = index;
    event.setDragData({ index: index });
    event.setDragFlags(DragFlag.MOVE);
    return true;
  }

  onDragEnter(event: DragEventInfo) {
    return true;
  }

  onDragLeave(event: DragEventInfo) {
    return true;
  }

  onDragOver(event: DragEventInfo) {
    return true;
  }

  onDrop(event: DragEventInfo, targetIndex: number) {
    if (this.draggedIndex !== -1) {
      const draggedItem = this.items[this.draggedIndex];
      this.items.splice(this.draggedIndex, 1);
      this.items.splice(targetIndex, 0, draggedItem);
      this.draggedIndex = -1;
    }
    return true;
  }

  onDragEnd(event: DragEventInfo) {
    this.draggedIndex = -1;
    return true;
  }

  build() {
    Column({ space: 50 }) {
      WaterFlow({
        space: 10,
        columns: 2
      }) {
        ForEach(this.items, (item, index) => {
          Text(item)
            .width('100%')
            .height(100)
            .backgroundColor('#FFA500')
            .onDragStart((event) => this.onDragStart(event, index))
            .onDragEnter(this.onDragEnter)
            .onDragLeave(this.onDragLeave)
            .onDragOver(this.onDragOver)
            .onDrop((event) => this.onDrop(event, index))
            .onDragEnd(this.onDragEnd)
        }, item => item)
      }
    }
  }
}