控制器策略/垃圾收集（销毁） [英] Controller Strategy / Garbage Collection (destroy)
问题描述
我将以User为例：
我想要做的是获取来自数据库的用户模型...然后将其包装在UserController中，并将模型设置为content属性...然后在View中，我想绑定到控制器功能，以及针对模型级数据的 controller.content 。所以控制器可能看起来像：
App.UserViewController = Em.Object.create（{
content：userRecord ，
isFollowingBinding：'content.you_follow'，
toggleFollow：function（）{
使服务器调用更改以下标志
}
}）;
然后视图可以绑定到 {{controller.content.name}} 或 {{＃if controller.isFollowing}} 或 {{actiontoggleFollowingtarget =controller}}
，但是说我从数据库中获取用户模型的列表...我觉得应该发生的是每个模型都应该用控制器包装， 应该作为列表返回...所以该视图将有一个UserController的列表
顺便提一句，我已经做了这个..并且它工作得很好....除了每当我重新加载列表，我用新的控制器包装所有新的模型对象...随着时间的推移，内存中的控制器数量越来越大。在我的基础控制器类，我正在记录调用摧毁，我不会看到它有发生
当涉及到Em.View ...我知道每次从屏幕上删除它时，.destroy（）都会得到调用（我也记录它们）。所以如果我把我的代码移动到一个视图，我知道它会被毁坏和重建每一次...但我不觉得像toggleFollow（）应该是在视图中的功能...
这些问题：
- MVC是如何工作的？每个模型的实例包裹在该模型的控制器中？哪里可以为一个屏幕创建大量的控制器实例？
- 如果我按照这种方法，那么我负责destroy（）我创建的所有控制器？或者是我上面描述的功能真的意味着一个View，而Ember会创建/销毁它们，因为它们被添加/从屏幕上删除？还允许模板设计者决定他们需要什么功能（如果他们只需要 {{user.name}} ，那么无需实例化其他控制器/视图类...但如果他们需要切换按钮，那么他们可以在 {{＃查看App.UserViewController contentBinding =this}} ）
$ b
我重写了几次...希望这是有道理的。
我不会将每个用户包装到自己的控制器中。
而是将用户绑定到一个视图，例如 App.UserView ，并处理该视图上的 toggleFollow 。然后，此操作将将其操作委托给将处理服务器调用的控制器，请参阅 http://jsfiddle.net/ pangratz666 / hSwEZ /
Handlebars ：
< script type =text / x-handlebars>
{{#each App.usersController}}
{{#view App.UserView userBinding =thiscontrollerBinding =App.usersController}}
{{user.name}}
{{#if isFollowing}}
< a {{actiontoggle以下}} class =clickable> stop following< / a>
{{else}}
< a {{actiontoggle以下}} class =clickable>开始跟随< / a>
{{/ if}}
{{#if user.isSaving}}保存... {{/ if}}
{{/ view}}
{{/每个}}
< / script>
JavaScript ：
App.usersController = Ember.ArrayProxy.create（{
content： ]，
toggleFollowing：function（user）{
user.set（'isSaving'，true）;
Ember.run.later（function（）{
user.toggleProperty（'you_follow'）;
user.set（'isSaving'，false）;
}，1000）;
}
}）;
App.UserView = Ember.View.extend（{
isFollowingBinding：'user.you_follow'，
toggleFollowing：function（）{
var user = this。 get（'user'）;
var controller = this.get（'controller'）;
controller.toggleFollowing（user）;
}
}）;
Trying to figure out the "ember best practices" for my app, regarding MVC. also for reference, I'm using ember-data, ember-layout, and ember-route-manager.
I'll use User as an example:
what I feel like I want to do is to get a User model from the database... then wrap it in a UserController, and set the model on a "content" property... then in a View, I want to bind to the controller for some functionality, and to the controller.content for model-level data. so a controller might look something like:
App.UserViewController = Em.Object.create({
content: userRecord,
isFollowingBinding : 'content.you_follow',
toggleFollow: function() {
make server call to change following flag
}
});
then the view could bind to the {{controller.content.name}}, or {{#if controller.isFollowing}}, or {{action "toggleFollowing" target="controller"}}
but say I get a list of User models back from the database... I feel like what should happen is that each of those models should be wrapped with a controller, and that should be returned as a list... so the view would have a list of UserControllers
Incidentally, I've done this... and it is working nicely.... except that everytime I reload the list, I wrap all of the new model objects with new controllers... and over time, the # of controllers in memory get larger and larger. on my base Controller class, I'm logging calls to "destroy", and I dont see it ever happening
when it comes to Em.View... I know that everytime it is removed from the screen, .destroy() gets calls (I am logging those as well). so if I were to move my code into a view, i know it will get destroyed and recreated everytime... but I dont feel like the functionality like toggleFollow() is supposed to be in view...
SO QUESTIONS:
- is this how MVC is supposed to work? every instance of a model wrapped in a controller for that model? where there could be lots of controller instances created for one screen?
- if I go down this approach, then I'm responsible for destroy()ing all of the controllers I create?
- or is the functionality I've described above really meant for a View, and them Ember would create/destroy them as they are added/removed from the screen? also allowing template designers to decide what functionality they need (if they just need the {{user.name}}, theres no need to instantiate other controller/view classes... but if they need a "toggle" button, then they could wrap that part of the template in {{#view App.UserViewController contentBinding="this"}} )
I re-wrote this a few times... hopefully it makes sense....
I wouldn't wrap every user into an own controller.
Instead I would bind the user to a view, say App.UserView and handle the action toggleFollow on that view. This action will then delegate it's action to a controller which will handle the server call, see http://jsfiddle.net/pangratz666/hSwEZ/
Handlebars:
<script type="text/x-handlebars" >
{{#each App.usersController}}
{{#view App.UserView userBinding="this" controllerBinding="App.usersController"}}
{{user.name}}
{{#if isFollowing}}
<a {{action "toggleFollowing"}} class="clickable" >stop following</a>
{{else}}
<a {{action "toggleFollowing"}} class="clickable" >start following</a>
{{/if}}
{{#if user.isSaving}}saving ...{{/if}}
{{/view}}
{{/each}}
</script>
JavaScript:
App.usersController = Ember.ArrayProxy.create({
content: [],
toggleFollowing: function(user) {
user.set('isSaving', true);
Ember.run.later(function() {
user.toggleProperty('you_follow');
user.set('isSaving', false);
}, 1000);
}
});
App.UserView = Ember.View.extend({
isFollowingBinding: 'user.you_follow',
toggleFollowing: function() {
var user = this.get('user');
var controller = this.get('controller');
controller.toggleFollowing(user);
}
});
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