自定义loading指令
directives/MyLoading/index.vue:
<template> <div class="loading-wrapper"> <div class="loading-content"> <img width="50" height="50" src="./loading.gif" /> <!-- 需要一个gif图片 --> <p class="title">{{ title }}</p> </div> </div> </template> <script> export default { data() { return { title: '正在加载中...' } } } </script> <style lang="less" scoped> .loading-wrapper { position: absolute; top: 50%; left: 50%; transform: translate3d(-50%, -50%, 0); .loading-content { width: 100%; text-align: center; .title { line-height: 20px; font-size: 12px; margin: 0; } } } </style>
directives/MyLoading/index.js:
import Vue from 'vue' import MyLoading from './index.vue' const myLoading = { inserted(el, binding) { const Loading = Vue.extend(MyLoading) const loading = new Loading().$mount() el.instance = loading if (binding.value) append(el) }, update(el, binding) { if (binding.value !== binding.oldValue) binding.value ? append(el) : remove(el) } } function append(el) { el.appendChild(el.instance.$el) } function remove(el) { el.removeChild(el.instance.$el) } export default myLoading
main.js:
import myLoading from '@/directives/MyLoading/index'
Vue.directive('myLoading', myLoading)
使用:(App.vue)
<template> <div id="app"> <ul v-myLoading="!list.length"> <li v-for="item in list" :key="item.id"> {{ item.title }} </li> </ul> </div> </template> <script> import axios from 'axios' export default { data() { return { list: [] } }, async created() { const res = await axios.get('https://jsonplaceholder.typicode.com/todos?_limit=5') this.list = res.data } } </script>
效果:当接口数据未返回时显示loading,返回结果时关闭loading
注意:用length去判断不够准确,因为length可能为0,应该以接收返回code码或其他标识为准