vue实现拖拽，可实现排序拖拽和自由拖拽（vuedraggable）

vuedraggable是一个vue的拖拽插件，可实现排序拖拽和自由拖拽，使用步骤和代码示例如下：

1、安装vuedraggable

npm install vuedraggable

2、页面引入

import draggable from 'vuedraggable';

3、示例：

 实现顺序拖拽：

这种是最常规的简单用法。可用于列表拖拽排序等。拖拽后的componentList就是按照顺序排列好的。

<template>
  <div class='testPage' ref='testPage'>
    <draggable
      :list="componentList"
      ghost-class="ghost"
      chosen-class="chosenClass"
      animation="300"
      @start="onStart"
      @end="onEnd"
      class="draggable"
    >
      <template #item="{ element }">
        <div class='item' style='width: 200px; height: 40px; border: 1px solid #EEEEEE;'>
           {{element.name}}
        </div>
      </template>
    </draggable>
  </div>
</template>

import draggable from 'vuedraggable';

export default {
  name: 'wel',
  components: {draggable},
  data() {
    return {
      componentList: [
        {
          id: 1,
          name: '测试1'
        },
        {
          id: 2,
          name: '测试2'
        },
        {
          id: 3,
          name: '测试3'
        },
        {
          id: 4,
          name: '测试4'
        },
        {
          id: 5,
          name: '测试5'
        }
      ],
      offsetX: 0,
      offsetY: 0,
      pageY: 0,
      pageX: 0
    };
  },
  computed: {},
  created() {},
  methods: {
    onStart() {

    },
    onEnd(e) {

    }
  },
};

.testPage {
  .draggable {
    width: 100%;
    height: 100%;
    position: relative;
  }
  .item {
    background: #FFFFFF;
  }
  .item:hover {
    cursor: move;
  }
  .ghost {
    border: solid 1px rgb(19, 41, 239);
  }
  .chosenClass {
    background-color: #f1f1f1;
  }
}

实现随意位置拖拽：

可随意位置拖拽，不用相邻，也不用排序，其实就是在原基础上把所有元素绝对定位，然后动态计算出移动后元素的位置，动态设置top和left值。

<template>
  <div class='testPage' ref='testPage'>
    <draggable
      :list="componentList"
      ghost-class="ghost"
      chosen-class="chosenClass"
      animation="300"
      @start="onStart"
      @end="onEnd"
      class="draggable"
      :sort='false'
    >
      <template #item="{ element }">
        <div class='item' style='width: 200px; height: 200px; position: absolute;  border: 1px solid #EEEEEE;' @mousedown='mousedownHandle'>
        {{element.name}}
        </div>
      </template>
    </draggable>
  </div>
</template>

import draggable from 'vuedraggable';

export default {
  name: 'wel',
  components: {draggable},
  data() {
    return {
      componentList: [
        {
          id: 1,
          name: '测试1'
        },
        {
          id: 2,
          name: '测试2'
        },
        {
          id: 3,
          name: '测试3'
        },
        {
          id: 4,
          name: '测试4'
        },
        {
          id: 5,
          name: '测试5'
        }
      ],
      offsetX: 0,
      offsetY: 0,
      pageY: 0,
      pageX: 0
    };
  },
  computed: {},
  created() {},
  methods: {
    onStart() {

    },
    onEnd(e) {
      e.item.style.top = e.originalEvent.pageY - this.offsetY - this.pageY + 'px';
      e.item.style.left = e.originalEvent.pageX - this.offsetX - this.pageX + 'px';
    },
    mousedownHandle(e) {
      this.offsetX = e.offsetX;
      this.offsetY = e.offsetY;
      var rectInfo = this.$refs.testPage.getBoundingClientRect();
      this.pageX = rectInfo.left;
      this.pageY = rectInfo.top;
    }
  },
};

.testPage {
  background: url("@/assets/images/map_bg.png") no-repeat center center !important;
  background-size: 100% 100%;
  position: relative;
  .draggable {
    width: 100%;
    height: 100%;
    position: relative;
  }
  .item {
    background: #FFFFFF;
  }
  .item:hover {
    cursor: move;
  }
  .ghost {
    border: solid 1px rgb(19, 41, 239);
  }
  .chosenClass {
    background-color: #f1f1f1;
  }
}