問題描述

<el-tree ref='permissions_tree' :data='permissions' :props='basicConfig.defaultProps' show-checkbox node-key='id' :render-content='renderNode'></el-tree>

mounted () { console.log(this.$refs.permissions_tree);}

在 mounted 中打印輸出的是undefined！這是為什么？

我在表格中渲染的按鈕，第一次點擊調用 console.log(this.$refs.permissions_tree);得到的也是 undefined，第二次就能正常獲取到組件了

{ title: ’操作’, key: ’action’, align: ’center’, render: (h, params) => { return h(’p’, [h(’Button’, { props: { type: ’primary’, size: ’small’ }, style: { marginRight: ’5px’ }, on: { click: () => { this.userForm.staffid = params.row.staffid; this.userForm.name = params.row.name; this.userForm.phoneticize = params.row.phoneticize; this.userForm.gender = params.row.gender; this.userForm.mobile = params.row.mobile; this.userForm.telephone = params.row.telephone; this.userForm.identification = params.row.identification; this.userForm.positions = params.row.positions; this.userForm.permissions = params.row.permissions; this.userFormShow = true; console.log(this.$refs.permissions_tree); //這里 } }}, ’編輯’) ]); }}

問題解答

可能你用v-if來切換組件展示，所以要在下一個tick才能獲取到

this.$nextTick(() => { console.log(this.$refs.permissions_tree);});回答2：

寫在

this.$nextTick(() => {})

里試一下

外層組件是不是使用了v-if，換成v-show 試一下

調用這個方法this.$nextTick(function () {

// 里面打印 })