基于iview的tree组件拓展了树节点拖拽功能，默认使用了远程加载

src/components/tree-drag/index.js

@@ -0,0 +1,2 @@
+import Index from './index.vue'
+export default Index

src/components/tree-drag/index.vue

@@ -0,0 +1,242 @@
+<template>
+  <div>
+    <Tree
+      :data="[{
+        title: '',
+        nodeKey: 0,
+        loading: false,
+        children: []
+      }]"
+      :load-data="buildChild"
+      @on-select-change="handlerTreeSelected"
+      @on-toggle-expand="handlerTreeExpand"
+      :render="renderContent"
+    />
+  </div>
+</template>
+
+<script>
+const TREE_NODE_CLASS = 'ivu-tree-children'
+const TREE_NODE_HOVER_PREFIX = 'tree-hover-'
+const APPEND_BEFORE = 'before'
+const APPEND_INNER = 'inner'
+const APPEND_AFTER = 'after'
+let READY_TO_APPEND = null
+let APPEND_TO = null
+let APPEND_TARGET = null
+export default {
+  name: 'tree-drag',
+  props: {
+    getChild: {
+      type: Function,
+      default: null
+    }
+  },
+  data () {
+    return {
+    }
+  },
+  methods: {
+    handlerTreeSelected (nodeList, node) {
+      if (node.loading) return
+      if (!node.expand) {
+        this.buildChild(node)
+      }
+      this.$set(node, 'selected', true)
+      this.$set(node, 'expand', !node.expand)
+      nodeList.filter(n => n.node.selected && n.nodeKey !== node.nodeKey).map(n => {
+        this.$set(n.node, 'selected', false)
+      })
+      this.$emit('on-select', node)
+    },
+    handlerTreeExpand (node) {
+      if (node.loading) return
+      if (node.expand) {
+        this.buildChild(node)
+      }
+    },
+    async buildChild (node, child) {
+      if (node.loading === void (0)) {
+        if (child) {
+          if (node.children) {
+            if (node.children.length > 0) {
+              node.children.push(child)
+              return
+            }
+          } else {
+            this.$set(node, 'children', [child])
+            return
+          }
+        }
+        return
+      }
+      this.$set(node, 'loading', true)
+      // 接口获取数据加载子节点
+      const data = (await this.getChild(node)) || []
+      if (child) {
+        data.push(child)
+      }
+      if (data.length) {
+        this.$set(node, 'children', data)
+        this.$set(node, 'expand', true)
+      } else {
+        this.$delete(node, 'children')
+      }
+      this.$delete(node, 'loading')
+    },
+    handlerDragstart (e, { data }) {
+      const { target } = e
+      target.style.opacity = '.5'
+      READY_TO_APPEND = data
+    },
+    handlerDragOver (e, { data }) {
+      if (READY_TO_APPEND === data) {
+        APPEND_TARGET = null
+        return
+      }
+      const { offsetY, target } = e
+      const offset = offsetY / target.offsetHeight
+      if (offset <= 0.33) {
+        APPEND_TO = APPEND_BEFORE
+      } else if (offset > 0.33 && offset < 0.66) {
+        APPEND_TO = APPEND_INNER
+      } else if (offset >= 0.66) {
+        APPEND_TO = APPEND_AFTER
+      }
+      this.setBorderOffsetElement(target)
+      APPEND_TARGET = data
+    },
+    handlerDragend (e, { root, node, data }) {
+      const { target } = e
+      this.clearBorder()
+      target.style.opacity = '1'
+      if (!APPEND_TARGET || this.isChildren(data, APPEND_TARGET)) {
+        return
+      }
+      // 从树上移除节点，就是拖动的节点
+      const removeNode = () => {
+        const parent = root.find(el => el.children && el.children.indexOf(data.nodeKey) > -1).node
+        const index = parent.children.indexOf(data)
+        parent.children.splice(index, 1)
+      }
+      removeNode()
+
+      // 把移除的节点根据前后位置及父级关系添加回去
+      const doAppend = (isBefore) => {
+        const parent = root.find(el => el.children && el.children.indexOf(APPEND_TARGET.nodeKey) > -1).node
+        const index = parent.children.indexOf(APPEND_TARGET) + (isBefore ? 0 : 1)
+        parent.children.splice(index, 0, data)
+        if (parent.children.length === 0) {
+          delete parent.children
+        }
+      }
+
+      switch (APPEND_TO) {
+        case APPEND_BEFORE:
+          doAppend(true)
+          break
+        case APPEND_AFTER:
+          doAppend(false)
+          break
+        case APPEND_INNER:
+          // 先展开
+          this.$set(APPEND_TARGET, 'expand', true)
+          // 加载内容
+          this.buildChild(APPEND_TARGET, data)
+          break
+      }
+      this.$emit('on-drag', data, APPEND_TARGET, APPEND_TO, e)
+      READY_TO_APPEND = null
+      APPEND_TO = null
+      APPEND_TARGET = null
+    },
+    isChildren (node, child) {
+      const { children } = node
+      if (!children || !children.map) return false
+      let flag = children.some(c => c.nodeKey === child.nodeKey)
+      if (!flag) {
+        children.map(node => {
+          flag = this.isChildren(node, child)
+        })
+      }
+      return flag
+    },
+    setBorderOffsetElement (target) {
+      this.clearBorder()
+      let ul = target
+      while (ul.className !== TREE_NODE_CLASS) {
+        ul = ul.parentElement
+      }
+      ul.className = `${TREE_NODE_CLASS} ${TREE_NODE_HOVER_PREFIX}${APPEND_TO}`
+    },
+    clearBorder () {
+      let temp = document.querySelectorAll(`
+        .${TREE_NODE_HOVER_PREFIX}${APPEND_BEFORE},
+        .${TREE_NODE_HOVER_PREFIX}${APPEND_INNER},
+        .${TREE_NODE_HOVER_PREFIX}${APPEND_AFTER}
+      `)
+      for (let i = 0; i < temp.length; i++) {
+        temp[i].className = TREE_NODE_CLASS
+      }
+    },
+    renderContent (h, treeData) {
+      const { root, data } = treeData
+      const { handlerDragstart, handlerDragOver, handlerDragend } = this
+      if (root.length === 1) {
+        this.handlerTreeSelected(root, data)
+      }
+      if (data.nodeKey === 0) {
+        return null
+      } else {
+        return (
+          <span
+            draggable="true"
+            on-dragstart={(e) => handlerDragstart(e, treeData)}
+            on-dragover={(e) => handlerDragOver(e, treeData)}
+            on-dragend={(e) => handlerDragend(e, treeData)}
+            class={{ 'ivu-tree-title': true, 'ivu-tree-title-selected': data.selected }}
+            onClick={() => this.handlerTreeSelected(root, data)}
+          >
+            <Icon type={data.icon} size="18" />
+            {data.title}
+          </span>
+        )
+      }
+    }
+  }
+}
+</script>
+<style lang="less">
+// 隐藏根节点
+.ivu-tree > ul > li > span {
+  display: none;
+}
+// 去掉根节点下的padding
+.ivu-tree > ul > li > ul {
+  padding: 0;
+}
+.ivu-tree ul li{
+  margin: 0!important;
+}
+.ivu-tree-arrow, .ivu-tree-title{
+  padding: 5px 0!important;
+}
+.ivu-tree-title{
+  width: 100%;
+}
+.ivu-tree ul{
+  border: 1px solid transparent;
+}
+.tree-hover-before{
+  border-top-color: #2d8cf0!important;
+}
+.tree-hover-inner{
+  background-color: #2d8cf0;
+  span{
+    color: #fff;
+  }
+}
+.tree-hover-after {
+  border-bottom-color: #2d8cf0!important;
+}
+</style>

src/locale/lang/en-US.js

@@ -28,6 +28,7 @@ export default {
   'export-excel': 'Export Excel',
   tools_methods_page: 'Tools Methods',
   drag_list_page: 'Drag-list',
+  tree_drag: 'Tree Dragger',
   i18n_page: 'Internationalization',
   modalTitle: 'Modal Title',
   content: 'This is the modal box content.',

src/locale/lang/zh-CN.js

@@ -28,6 +28,7 @@ export default {
   'export-excel': '导出excel',
   tools_methods_page: '工具函数',
   drag_list_page: '拖拽列表',
+  tree_drag: '树节点拖拽',
   i18n_page: '多语言',
   modalTitle: '模态框题目',
   content: '这是模态框内容',

src/locale/lang/zh-TW.js

@@ -28,6 +28,7 @@ export default {
   'export-excel': '導出excel',
   tools_methods_page: '工具函數',
   drag_list_page: '拖拽列表',
+  tree_drag: '树节点拖拽',
   i18n_page: '多語言',
   modalTitle: '模態框題目',
   content: '這是模態框內容',

src/router/routers.js

@@ -134,6 +134,15 @@ export default [
         },
         component: () => import('@/view/components/drag-list/drag-list.vue')
       },
+      {
+        path: 'tree_drag',
+        name: 'tree_drag',
+        meta: {
+          icon: 'ios-expand',
+          title: '树节点拖拽'
+        },
+        component: () => import('@/view/components/tree-drag/index.vue')
+      },
       {
         path: 'drag_drawer_page',
         name: 'drag_drawer_page',

src/view/components/tree-drag/index.vue

@@ -0,0 +1,77 @@
+<template>
+  <div class="tree-drag">
+    <div>
+      <p>选择了：{{selected.title}}</p>
+      <TreeDrag :getChild="getChild" @on-select="handlerSelect" @on-drag="handlerDrag"/>
+    </div>
+    <div>
+      <p>拖拽历史</p>
+      <p v-for="(json, index) in dragHis" :key="index">
+        ID: {{json.from.id}}({{json.from.title}}) --->> ID: {{json.to.id}}({{json.to.title}})
+        <strong>Position: {{json.position}}</strong>
+      </p>
+    </div>
+  </div>
+</template>
+
+<script>
+import TreeDrag from '_c/tree-drag'
+export default {
+  name: 'tree-drag-demo',
+  components: { TreeDrag },
+  data () {
+    return {
+      selected: {},
+      dragHis: []
+    }
+  },
+  methods: {
+    getChild (node) {
+      return new Promise((resolve, reject) => {
+        setTimeout(() => {
+          const data = []
+          // 接口获取数据加载子节点
+          for (let i = 0; i < 10; i++) {
+            const child = {
+              title: `测试节点${node.nodeKey}-${i}`,
+              id: `${node.nodeKey}${i}`,
+              loading: false,
+              children: []
+            }
+            // 模拟标记第5个开始没有子节点
+            // 不包含loading和children属性则不会有展开的箭头，遵循官方tree使用
+            if (i >= 5) {
+              delete child.loading
+              delete child.children
+            }
+            data.push(child)
+          }
+          resolve(data)
+        }, 1000)
+      })
+    },
+    handlerSelect (node) {
+      this.selected = node
+    },
+    handlerDrag (from, to, position, e) {
+      this.dragHis.push({
+        from, to, position, e
+      })
+    }
+  }
+}
+</script>
+<style lang="less">
+.tree-drag {
+  display: flex;
+  &>div{
+    flex: 1;
+  }
+  &>div:first-child{
+    border-right: 1px solid #dcdee2;
+  }
+  &>div:last-child{
+    padding-left: 16px;
+  }
+}
+</style>