树状表格子节点移动 - 在Vue.js中实现上下移动子节点的表格功能

功能介绍

本文介绍了如何在Vue.js框架下实现一个树状表格，其中支持选择子节点行的上下移动。通过这个功能，用户可以方便地改变子节点的顺序。代码示例和详细的实现步骤将展示如何使用Vue.js的相关特性和组件实现这个功能。通过本文的介绍，您可以轻松了解如何在您的Vue.js项目中应用这个功能，以满足您的特定需求。

示例

代码

视图部分

实现父节点选择的代码

在上次选中父节点的代码基础上加上操作行，生成上下移动的按钮：

html 复制代码

      <el-table-column align="center">
        <template slot-scope="scope" v-if="!scope.row.children">
          <el-button v-show="!validateOperate(scope.row, 'up')" size="mini" icon="el-icon-top" plain
            @click="handleSort(scope.row, 'up')">
          </el-button>
          <el-button v-show="!validateOperate(scope.row, 'down')" size="mini" icon="el-icon-bottom" plain
            @click="handleSort(scope.row, 'down')"></el-button>
        </template>
      </el-table-column>

新增列定义，用于显示上移和下移按钮。<template> 标签中定义了使用 slot-scope 来访问作用域插槽，在这个作用域下，使用了两个 <el-button> 元素来展示上移和下移按钮。为了使第一行与最后一行只有下移或上移，这里通过绑定 v-show 来控制按钮的显示与隐藏，根据 validateOperate() 方法的返回值确定按钮是否可见。@click 侦听器则会触发 handleSort() 方法来完成所在行的移动。

逻辑部分

组件数据和选中父节点的代码相同，获取tableData后，如果没有index，则自己遍历加上该属性。

methods对象新增方法：

getParent(id) 方法用于获取拥有指定子行 id 的父级行，它通过遍历 this.tableData 数组来寻找子行所属的父行。

javascript 复制代码

    getParent(id) {
      let result = [];
      this.tableData.some(item => {
        item.children.some(d => {
          if (d.id == id) result = item;
        })
      });
      return result;
    }

validateOperate(row, type) 方法用于根据指定的操作类型（上移或下移）检查当前行是否可进行该操作。首先判断是否最内层的子树，对于上移操作，当前行的索引为0时返回true，隐藏上移按钮；对于下移操作，当前行的索引等于自身所处children数组的长度减1时返回true，隐藏下移按钮。

javascript 复制代码

    validateOperate(row, type) {
      if (!row.children) {
        if (type == 'up' && row.index == 0) {
          return true;
        }
        else if (type == 'down') {
          return this.getParent(row.id).children.length - 1 == row.index;
        }
        else {
          return false;
        }
      }
    }

handleSort(row, type) 方法用于处理行的上移和下移操作。它首先获取该行的父级行和父级行的 ID，并定义一个标志变量 downFlag。然后通过遍历 parent.children 数组来查找需要进行上移或下移操作的行，并进行相应的移动和调整索引的操作。最后，更新父级行的子行列表和相关数据。

javascript 复制代码

    handleSort(row, type) {
      let parent = this.getParent(row.id);
      let parentId;
      let downFlag = true;

      this.tableData.forEach(item => {
        if (item.children === parent) parentId = item.id;
      });

      console.log(parent);
      parent.children.some(item => {
        if (type == 'up') {
          if (item.index == row.index - 1) {
            parent.children.splice(row.index, 1);
            parent.children.splice(item.index, 0, row);
            parent.children.forEach((child, index) => child.index = index);
            this.tableData.forEach(data => {
              if (data.id === parentId) data.children = parent.children;
            });
          }
        } else if (type == 'down' && downFlag) {
          if (item.index == row.index + 1) {
            parent.children.splice(row.index, 1);
            parent.children.splice(item.index, 0, row);
            parent.children.forEach((child, index) => child.index = index);
            this.tableData.forEach(data => {
              if (data.id === parentId) data.children = parent.children;
            });
            downFlag = false;
          }
        }
      })
    }

完整代码

javascript 复制代码

<template>
  <div>
    <el-table v-loading="loading" :data="tableData" style="width: 100%;margin: 20px;" row-key="id" border
      default-expand-all :tree-props="{ children: 'children' }">
      <el-table-column width="60" align="center">
        <template slot="header" slot-scope="scope">
          <el-checkbox :indeterminate="isIndeterminate" v-model="isFullChecked" @change="checkAllChange">
          </el-checkbox>
        </template>
        <template slot-scope="{row}" v-if="row.children">
          <el-checkbox :indeterminate="row.isIndeterminate" :value="row.checked" @change="checkRowChange(row)">
          </el-checkbox>
        </template>
      </el-table-column>

      <el-table-column prop="series" label="系列" align="center"></el-table-column>
      <el-table-column prop="num" label="编号" align="center"></el-table-column>
      <el-table-column prop="name" label="名字" align="center"></el-table-column>
      <el-table-column align="center">
        <template slot-scope="scope" v-if="!scope.row.children">
          <el-button v-show="!validateOperate(scope.row, 'up')" size="mini" icon="el-icon-top" plain
            @click="handleSort(scope.row, 'up')">
          </el-button>
          <el-button v-show="!validateOperate(scope.row, 'down')" size="mini" icon="el-icon-bottom" plain
            @click="handleSort(scope.row, 'down')"></el-button>
        </template>
      </el-table-column>
    </el-table>
  </div>
</template>

<script>
export default {
  data() {
    return {
      isFullChecked: false,
      isIndeterminate: false,
      loading: true,
      tableData: []
    }
  },
  mounted() {
    this.getList()
  },
  watch: {
    tableData() {
      this.isFullChecked = false;
      this.isIndeterminate = false;
    }
  },
  methods: {
    getList() {
      const tableData = [
        {
          id: 1,
          series: 'DDLC',
          children: [
            {
              id: 11,
              num: '1',
              name: 'monika',
              index: 0,
            },
            {
              id: 12,
              num: '2',
              name: 'nasuki',
              index: 1,
            },
            {
              id: 13,
              num: '3',
              name: 'sayori',
              index: 2,
            },
            {
              id: 14,
              num: '4',
              name: 'yuri',
              index: 3,
            }
          ]
        },
        {
          id: 2,
          series: 'Bloom Into You',
          children: [
            {
              id: 21,
              num: '11',
              name: 'nanami',
              index: 0,
            },
            {
              id: 22,
              num: '12',
              name: 'yuu',
              index: 1,
            }
          ]
        },
      ];
      tableData.forEach(item => {
        item.checked = false;
        item.isIndeterminate = false;
      })
      this.tableData = tableData;
      this.total = this.tableData.length;
      this.loading = false;
    },

    checkAllChange() {
      const recursionSetChecked = (item, checked) => {
        item.checked = checked;
        item.isIndeterminate = false;
      }
      this.isIndeterminate = false;
      this.tableData.forEach(item => recursionSetChecked(item, this.isFullChecked));
    },

    checkRowChange(data) {
      data.checked = !data.checked;
      const recursion = node => {
        if (node.children && node.children.length > 0)
          node.isIndeterminate = false;
        return node;
      };
      this.tableData.forEach(item => recursion(item));

      if (this.tableData.every(item => item.checked)) {
        this.isFullChecked = true;
      }
      else if (this.tableData.every(item => !item.checked)) {
        this.isFullChecked = false;
      }

      this.isIndeterminate = this.tableData.some(item => item.isIndeterminate)
        ? true
        : this.tableData.some(item => !item.checked) && this.tableData.some(item => item.checked);
    },

    getParent(id) {
      let result = [];
      this.tableData.some(item => {
        item.children.some(d => {
          if (d.id == id) result = item;
        })
      });
      return result;
    },

    validateOperate(row, type) {
      if (!row.children) {
        if (type == 'up' && row.index == 0) {
          return true;
        }
        else if (type == 'down') {
          return this.getParent(row.id).children.length - 1 == row.index;
        }
        else {
          return false;
        }
      }
    },

    handleSort(row, type) {
      let parent = this.getParent(row.id);
      let parentId;
      let downFlag = true;

      this.tableData.forEach(item => {
        if (item.children === parent) parentId = item.id;
      });

      console.log(parent);
      parent.children.some(item => {
        if (type == 'up') {
          if (item.index == row.index - 1) {
            parent.children.splice(row.index, 1);
            parent.children.splice(item.index, 0, row);
            parent.children.forEach((child, index) => child.index = index);
            this.tableData.forEach(data => {
              if (data.id === parentId) data.children = parent.children;
            });
          }
        } else if (type == 'down' && downFlag) {
          if (item.index == row.index + 1) {
            parent.children.splice(row.index, 1);
            parent.children.splice(item.index, 0, row);
            parent.children.forEach((child, index) => child.index = index);
            this.tableData.forEach(data => {
              if (data.id === parentId) data.children = parent.children;
            });
            downFlag = false;
          }
        }
      })
    }
  }
}
</script>