Vue之directives所遇小bug

自己在利用vue写todoList的时候遇到一个小bug,记录一下

写个指令,当双击进行编辑todo,让其自动聚焦,结果效果如下,

代码如下:

directives: {
    focus(el,bindings) {
        if(bindings.value) {
              el.focus();
         }
     }
}
<input v-focus="todo == t" type="text" v-show="todo == t"  v-model="todo.title" @blur="reset" @keyup.13="reset" >

多方查找原因,把自定义v-focus指令放末尾,就好了,代码如下:

<input type="text" v-show="todo == t"  v-model="todo.title" @blur="reset" @keyup.13="reset" v-focus="todo == t">

是否自定义指令都应放后面呢?这就需要以后验证了

完整代码如下:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <link rel="stylesheet" href="../node_modules/bootstrap/dist/css/bootstrap.css">
    <style>
        .del{
            text-decoration: line-through;
            color: #ccc!important;
        }
    </style>
</head>
<body>
    <div id="app">
        <div class="container">
            <div class="row">
                <div class="col-md-12">
                    <div class="panel panel-warning">
                        <div class="panel-heading">
                            <input type="text" v-model="value" class="form-control" @keydown.enter="add">
                        </div>
                        <div class="panel-body">
                            <ul class="list-group">
                                <li class="list-group-item" @dblclick="change(todo)" v-for="(todo,index) in todos" :key="index">
                                    <div v-show="todo != t" :class="{del: todo.isSelected}">
                                        <input type="checkbox" v-model="todo.isSelected">{{todo.title}}
                                        <button class="pull-right btn btn-danger btn-xs" @click="remove(index)">&bigotimes;</button>
                                    </div>
                                    <input type="text" v-show="todo == t"  v-model="todo.title" @blur="reset" @keyup.13="reset" v-focus="todo == t">
                                    <!-- 下面是错误代码,可以把上面的注释掉打开下面的对比下 -->
                                    <!-- <input v-focus="todo == t" type="text" v-show="todo == t"  v-model="todo.title" @blur="reset" @keyup.13="reset" > -->
                                </li>
                            </ul>
                        </div>
                        <div class="panel-footer">
                            <ul class="nav nav-pills">
                                <li role="presentation" class="active"><a href="#">全部</a></li>
                                <li role="presentation"><a href="#">已完成</a></li>
                                <li role="presentation"><a href="#">未完成</a></li>
                            </ul>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
    <script src="../node_modules/vue/dist/vue.js"></script>
    <script>
        let vm = new Vue({
            el:'#app',
            data:{
                todos:[],
                hash:'complete',//路径切换时 获取的hash值
                value:'',// 输入框中需要增加的内容,
                t:''//当前点击的那一个
            },
            created(){ //当vue创建时执行的方法
                //如果storage有 就用这里的值 没有就是空数组
                this.todos = JSON.parse(localStorage.getItem('todos')) || [{isSelected:true,title:'晚上回去睡觉'}];
            },
            watch:{  //watch默认 只监控一层,例如 todos 可以监控数组的变化,监控不到对象的变化
                todos:{
                    handler(){
                        localStorage.setItem('todos',JSON.stringify(this.todos));
                    },
                    deep:true
                }
            },
            methods:{
                addTodo(){
                    let todo = {isSelected:false,title:this.value};
                    this.todos.push(todo);
                    this.value = '';
                },
                remove(todo){
                    this.todos = this.todos.filter(item=>todo!==item);
                },
                change(todo){
                    //todo代表的是我当前点击的是哪一个,存储当前点击的这一项
                    this.t = todo;
                },
                reset(){
                    this.t = '';
                }
            },
            computed:{
                lists(){
                    if(this.hash === 'complete'){
                        return this.todos;
                    }
                    if(this.hash === 'finish'){
                        return this.todos.filter(item=>item.isSelected)
                    }
                    if(this.hash === 'unfinish'){
                        return this.todos.filter(item=>!item.isSelected)
                    }
                },
                total(){
                    //求出数组中为false的个数
                    //将数组中的true全部干掉,求出剩余length
                    return this.todos.filter(item=>!item.isSelected).length;
                }
            },
            directives:{ //指令,就是操作dom
                focus(el,bindings){
                    //bindings中有一个value属性 代表的是指令对应的值v-auto-focus="值"
                    if(bindings.value){
                        el.focus();
                    }
                    //console.log(el,bindings);
                }
            }
        });

        let listener = () => {
            let hash = window.location.hash.slice(1) || 'complete'; //如果打开页面没有hash默认是全部
            vm.hash = hash;
        };
        listener(); //页面一加载 就需要获取一次hash值,否则可能导致 回到默认hash
        window.addEventListener('hashchange',listener,false);
    </script>
</body>
</html>

 

posted @ 2019-02-19 22:54  卑面派对  阅读(757)  评论(0编辑  收藏  举报