3 回答this.todos.filter(todo => completed === todo.completed)

2 回答completed在什么地方被置為true的？

5 回答todo => completed === todo.completed這是什么寫法

3 回答all active completed 標(biāo)簽切換的時(shí)候，filteredTodos方法不起作用呢？

1 回答 <div :class="['todo-item', todo.completed ? 'completed':'']">