vue element el-transfer增加拖拽功能

芯资管项目要求el-transfer增加拖拽排序，左右上下互相拖拽功能；
原来的组件不支持拖拽，这里要用个第三方脱宅组件sortablejs

首先安装

 sudo npm i sortablejs --save-dev

html代码

  <template>
  <el-transfer ref="transfer" id="transfer" v-model="value" :data="data">
   <span slot-scope="{ option }" :draggable="!option.disabled" @dragstart="drag($event,option)">{{ option.key }} - {{ option.label }}</span>
  </el-transfer>
</template>```

create

  <script>

   import Sortable from 'sortablejs'

   export default {
      data() {
        const generateData = _ => {
          const data = []; for (let i = 1; i <= 15; i++) {
            data.push({
              key: i,
              label: `备选项 ${i}`,
              disabled: i % 4 === 0 });
          } return data;
        }; return {
          data: generateData(),
          value: [1, 4],
          draggingKey : null }
      },
      mounted() {
        const transfer = this.$refs.transfer.$el
        const leftPanel = transfer.getElementsByClassName("el-transfer-panel")[0].getElementsByClassName("el-transfer-panel__body")[0];
        const rightPanel = transfer.getElementsByClassName("el-transfer-panel")[1].getElementsByClassName("el-transfer-panel__body")[0];
        const rightEl = rightPanel.getElementsByClassName("el-transfer-panel__list")[0]
        Sortable.create(rightEl,{
          onEnd: (evt) => {
            const {oldIndex,newIndex} = evt;
            const temp = this.value[oldIndex] 
            if (!temp || temp === 'undefined') {
              return
            }// 解决右边最后一项从右边拖左边，有undefined的问题
            this.$set(this.value,oldIndex,this.value[newIndex])  
            this.$set(this.value,newIndex,temp)
          }
        })
        const leftEl = leftPanel.getElementsByClassName("el-transfer-panel__list")[0]
        Sortable.create(leftEl,{
          onEnd: (evt) => {
            const {oldIndex,newIndex} = evt;
            const temp = this.data[oldIndex] 
            if (!temp || temp === 'undefined') {
              return
            } // 解决右边最后一项从右边拖左边，有undefined的问题
            this.$set(this.data,oldIndex,this.data[newIndex]) 
            this.$set(this.data,newIndex,temp)
          }
        })
        leftPanel.ondragover = (ev) => {
          ev.preventDefault()
        }
        leftPanel.ondrop = (ev) => {
          ev.preventDefault();
          const index = this.value.indexOf(this.draggingKey) if(index !== -1){ this.value.splice(index,1)
          }
        }
        rightPanel.ondragover = (ev) => {
          ev.preventDefault()
        }
        rightPanel.ondrop = (ev) => {
          ev.preventDefault();  if(this.value.indexOf(this.draggingKey) === -1){ this.value.push(this.draggingKey)
          }
        }
      },
      methods: {
        drag(ev,option) { this.draggingKey = option.key
        }
      }

    } 
</script>

到此这篇关于vue element el-transfer增加拖拽功能的文章就介绍到这了,更多相关element el-transfer拖拽内容请搜索猪先飞以前的文章或继续浏览下面的相关文章希望大家以后多多支持猪先飞！