当我在终端中键入open <this_filename.html>时，它会打开页面，并且该页面上已经显示了todolist模型列表。怎么样？
这是代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<title>To-do App in Backbone.js</title>
<!-- ========= -->
<!-- CSS -->
<!-- ========= -->
<style type="text/css">
/* Hides bullet points from todo list */
#todoapp ul {
list-style-type: none;
}
</style>
</head>
<body>
<!-- ========= -->
<!-- Your HTML -->
<!-- ========= -->
<section id="todoapp">
<header id="header">
<h1>Todos</h1>
<input id="new-todo" placeholder="What needs to be done?" autofocus>
</header>
<section id="main">
<ul id="todo-list"></ul>
</section>
</section>
<div>
<p>Find the tutorial and code in <a href="http://adrianmejia.com/blog/2012/09/11/backbone-dot-js-for-absolute-beginners-getting-started/">here</a></p>
</div>
<!-- Templates -->
<script type="text/template" id="item-template">
<div class="view">
<input class="toggle" type="checkbox">
<label><%- title %></label>
</div>
</script>
<!-- ========= -->
<!-- Libraries -->
<!-- ========= -->
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.3.3/underscore-min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone.js/0.9.2/backbone-min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone-localstorage.js/1.0/backbone.localStorage-min.js" type="text/javascript"></script>
<!-- =============== -->
<!-- Javascript code -->
<!-- =============== -->
<script type="text/javascript">
'use strict';
var app = {}; // create namespace for our app
//--------------
// Models
//--------------
app.Todo = Backbone.Model.extend({
defaults: {
title: '',
completed: false
}
});
//--------------
// Collections
//--------------
app.TodoList = Backbone.Collection.extend({
model: app.Todo,
localStorage: new Store("backbone-todo")
});
// instance of the Collection
app.todoList = new app.TodoList();
//--------------
// Views
//--------------
// renders individual todo items list (li)
app.TodoView = Backbone.View.extend({
tagName: 'li',
template: _.template($('#item-template').html()),
render: function(){
this.$el.html(this.template(this.model.toJSON()));
return this; // enable chained calls
}
});
// renders the full list of todo items calling TodoView for each one.
app.AppView = Backbone.View.extend({
el: '#todoapp',
initialize: function () {
this.input = this.$('#new-todo');
app.todoList.on('add', this.addAll, this);
app.todoList.on('reset', this.addAll, this);
app.todoList.fetch(); // Loads list from local storage
},
events: {
'keypress #new-todo': 'createTodoOnEnter'
},
createTodoOnEnter: function(e){
if ( e.which !== 13 || !this.input.val().trim() ) { // ENTER_KEY = 13
return;
}
app.todoList.create(this.newAttributes());
this.input.val(''); // clean input box
},
addOne: function(todo){
var view = new app.TodoView({model: todo});
$('#todo-list').append(view.render().el);
},
addAll: function(){
this.$('#todo-list').html(''); // clean the todo list
app.todoList.each(this.addOne, this);
},
newAttributes: function(){
return {
title: this.input.val().trim(),
completed: false
}
}
});
//--------------
// Initializers
//--------------
app.appView = new app.AppView();
</script>
</body>
</html>
在代码底部，此行：
app.appView = new app.AppView();实例化AppView。是否自动调用reset函数？我想我了解
addAll和addOne方法是如何定义的，但是我想知道首先是什么调用它们的？ todoList如何在页面上呈现？ 最佳答案
new app.AppView();
这将调用
initialize的app.AppView函数。initialize: function () {
// this is where addAll is called
app.todoList.on('add', this.addAll, this);
app.todoList.on('reset', this.addAll, this);
app.todoList.fetch(); // Loads list from local storage
},
侦听器绑定到集合
add的reset和app.todoList事件，并使用this.addAll作为回调。在集合上调用
.fetch()时，它将向其中添加新模型，从而触发add事件，该事件随后触发回调this.addAll。但是我认为，对于最新的Backbone版本，它应该使用
listenTo，这是on的更好版本：initialize: function () {
this.listenTo(app.todoList, {
'add': this.addOne, // on the add event, only use addOne
'reset': this.addAll // on collection reset, re-render everything
});
app.todoList.fetch(); // Loads list from local storage
},
listenTo vs on