uniappを使用してドラッグアンドドロップソート機能を実装する

<template>
  <view>
    <view class="list" v-for="(item, index) in list" :key="index" @touchstart="startDrag(index)" @touchmove="dragging($event, index)" @touchend="endDrag(index)">
      {{ item }}
    </view>
  </view>
</template>

<script>
export default {
  data() {
    return {
      list: [1, 2, 3, 4, 5],
      draggingIndex: -1,
      placeholderIndex: -1,
    };
  },
  methods: {
    startDrag(index) {
      this.draggingIndex = index;
      this.placeholderIndex = index;
    },
    dragging(event, index) {
      const touch = event.touches[0];
      const offsetY = touch.clientY;
      const draggingItemHeight = 25; // 拖拽项的高度
      const draggingItemIndex = Math.floor(offsetY / draggingItemHeight);
      if (draggingItemIndex !== this.placeholderIndex) {
        this.list.splice(this.placeholderIndex, 1); // 移除占位元素
        this.list.splice(draggingItemIndex, 0, this.list[this.draggingIndex]); // 将拖拽项插入新的位置
        this.placeholderIndex = draggingItemIndex; // 更新占位元素的位置
      }
    },
    endDrag(index) {
      this.draggingIndex = -1;
      this.placeholderIndex = -1;
    },
  },
};
</script>