javascript - 如何将输入的值添加到 li 列表？

Question

我正在尝试将输入值添加为 <li>到 <ul>列表。

我可以通过将值绑定(bind)到 lis 的数组列表来添加它。但是，当我清理输入字段时，它不会留在那里。我该如何解决这个问题？

HTML 代码:

<div id="app">
  <h1>{{ message }}</h1>
  <form v-on:submit.prevent="addNewTodo">
    <input type="text" v-model="todo.task">
    <button type="submit">Add todo</button>
  </form>

  <ul>
    <li v-for="todo in todos" :class="{ completed: todo.isActive }" @click="$set(todo, 'isActive', !todo.isActive)">
     {{ todo.task }} <span v-on:click="deleteTodo">{{ todo.delete }}</span>
    </li>
  </ul>
</div>

JS 代码:

var app = new Vue({
  el: '#app',
  data: {
    message: 'List of things to do today',
    todos: [
      { task: 'Have breakfast', delete:'(x)'},
      { task: 'Go to the gym', delete:'(x)'},
      { task: 'Study Vuejs', delete:'(x)'}
    ],
    todo: {task: '', delete: '(x)'}
  },
  methods: {
    addNewTodo: function(){
      this.todos.push( this.todo );
    },
    deleteTodo: function(){
      this.todos.shift( this.todo )
    },
  }
});

这里有一个 JSfiddle 示例:https://jsfiddle.net/mercenariomode/gwd34815/1/

Answer 1

您需要更改对象引用，但在您的情况下，最好将“v-model”绑定(bind)到“task”属性

HTML 代码:

<form v-on:submit.prevent="addNewTodo">
    <input type="text" v-model="task">
    <button type="submit">Add todo</button>
</form>

JS 代码:

el: '#app',
  data: {
    message: 'List of things to do today',
    todos: [
      { task: 'Have breakfast', delete:'(x)'},
      { task: 'Go to the gym', delete:'(x)'},
      { task: 'Study Vuejs', delete:'(x)'}
    ],
    task: '',
}

并在addNewTodo方法中实现向数组添加对象的逻辑

addNewTodo: function(){
        let todo = {task: this.task, delete: '(x)'};
        this.todos.push(todo);

        this.task = ''; // clear data in input
},

JSFiddle:https://jsfiddle.net/nm29yq7d/1/