如何和何时使用Ember.Application注册和注入方法？ [英] How and when to use Ember.Application register and inject methods?

问题描述

我正在尝试了解如何使用Ember.Application 注册& 注入方法

I'm trying to understand how to use Ember.Application register & inject methods

这些函数的用例是什么？
他们如何使用和什么时候？

我真的很想知道！

推荐答案

默认情况下，Ember在使用主要约定启动应用程序时执行依赖注入，例如，如果您使用ember-data，那么 store 类注入到您的应用程序中的每个路由和控制器中，以便稍后获取通过在任何路由或控制器内简单地执行 this.get（'store'）的引用。

Ember by default does dependency injection when it boots your application using mostly conventions, for example if you use ember-data then an instance of the store class is injected in every route and controller in your application, so you can later get a reference by simply doing this.get('store') inside any route or controller.

是一个代码提取，其中默认的存储获取注册（取自源）

For example here is a code extract where the default store get's registered (taken from the source)

Ember.onLoad('Ember.Application', function(Application) {
  Application.initializer({
    name: "store",

    initialize: function(container, application) {
      application.register('store:main', application.Store);
      ...
    }

    container.lookup('store:main');
  }
});

然后注入（源）

Application.initializer({
  name: "injectStore",

  initialize: function(container, application) {
    application.inject('controller', 'store', 'store:main');
    application.inject('route', 'store', 'store:main');
    application.inject('dataAdapter', 'store', 'store:main');
  }
  ...
});

换句话说，注册和 inject 是注册依赖关系的方法，并自己注入。

In other words register and inject are methods to register dependencies and inject them yourself.

我们假设你有一个 Session 对象，您在应用程序启动后的服务器请求中填充对象，并且您希望在每个控制器中引用该对象，可以执行以下操作：

Let's assume you have a Session object which you populate after a server request on application start, and which you want to have a reference to in every controller, you could do something like this:

var App = Ember.Application.create({
  ready: function(){
    this.register('session:current', App.Session, {singleton: true});
    this.inject('controller', 'session', 'session:current');
  }
});

App.Session = Ember.Object.extend({
  sessionHash: ''
});

此代码将设置会话每个控制器实例到一个单例实例 App.Session ，所以你可以在任何控制器中执行 this.get（'session'）并获得引用，并且由于它被定义为单例，它将始终是相同的会话对象。

This code would set the session property of every controller instance to a singleton instance of App.Session, so you could in any controller do this.get('session') and get a reference to it, and since it's defined as a singleton it would be always the same session object.

使用注册可以注册控制器，模型，视图或任意对象类型。 inject ，另一方面，可以注入给定类的所有实例。例如 inject（'model'，'session'，'session：current'）也会注入 session 与会话：当前实例到所有模型。要注入会话对象，让我们说到 IndexView 你可以做 inject（'view ：index'，'session'，'session：current'）。

With register you can register controllers, models, views, or any arbitrary object type. inject, in the other hand, can inject onto all instances of a given class. For example inject('model', 'session', 'session:current') would also inject the session property with the session:current instance into all models. To inject the session object, let's say onto the IndexView you could do inject('view:index', 'session', 'session:current').

尽管注册和 inject 非常强大，你应该明智地使用它们，只有在你真的知道没有其他方法来实现你的目标的情况下，我猜缺乏文档一个沮丧的指标。

Although register and inject are very powerful you should use them wisely and only in the case you really know there is no other way to achieve your goal, I guess the lack of documentation is an indicator for discouragement.

由于它主要是必须的提供一个解释的工作示例，它会发生： http://jsbin.com/usaluc/6/edit 。请注意，在示例中，我们可以通过使用 {{controller.session.sessionHash}}引用当前控制器的会话对象来简单地访问所提到的 sessionHash / code>在我们所在的每个路由中，这是我们通过在应用程序的每个控制器中注册和注入 App.Session 对象所做的工作的优点

Since It's mostly a must to provide a working example with an explanation, there it goes: http://jsbin.com/usaluc/6/edit. Notice how in the example we can simply access the mentioned sessionHash by referring to the current controller's session object with {{controller.session.sessionHash}} in every route we are in, this is the merit of what we have done by registering and injecting the App.Session object in every controller in the application.

希望有帮助。

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