How can I send a message / call a method on all itemController children instances in Ember?

Question

I'm trying to use the "Buffered Proxy" pattern on a collection of items in a form from a hasMany model. When complete, I'm trying to have a "Save" button, which triggers a save action, allow me to save all the as-yet unsaved changes I've made. More info on the BP in Ember:

http://coryforsyth.com/2013/06/27/ember-buffered-proxy-and-method-missing/

I can get all this to work fine with a top level model attribute, but I'm confused as to how to tell all my non-singleton itemControllers that I want them to save their buffers, then be able to call the grandparent to save the whole enchilada. I was hoping I'd be able to do something like this from the parent array controller:

actions: {

    saveStuff: function() {

        // Something like this possible?
        this.get('allTheNonSingletonItemControllerChildren').send('saveThoseBuffers'); 

    }

}

Child controller:

saveThoseBuffers: function() {

    var grandParent = this.get('parentController').get('parentController');

    this.applyBufferedChanges();
    grandParent.saveEntireRecord(); // Not sure how this would work yet - can't use 'needs' because none of these controllers are singletons.

}

Grandparent:

saveEntireRecord: function() {

    this.get('model').save().then(function() { 
        //other stuff;
    }

}

View is something like:

{{#each stuff in childitems itemController="childController"}}

    {{input type="text" value=stuff.name}}

{{/each}}

<button {{action 'saveStuff'}}>Save</button>

Nothing in the docs or SO has revealed the incantations for this.

UPDATE:

Based on a suggestion, I also tried:

children = this.get('content');

children.forEach(function(child) {

    child.send('saveThoseBuffers');

});

but received:

"Uncaught Error: Attempted to handle event saveThoseBuffers on while in state root.loaded.saved."

UPDATE 2:

Versions:

DEBUG: Ember      : 1.5.0-beta.2 ember.js:3496
DEBUG: Ember Data : 1.0.0-beta.7+canary.b45e23ba ember.js:3496
DEBUG: Handlebars : 1.3.0 ember.js:3496
DEBUG: jQuery     : 1.9.1 ember.js:3496

UPDATE 3:

Tried getting access to subcontrollers using:

var children = this.get('_subControllers');

That always returns an empty array, regardless of where itemController is set (in the ArrayController or in each loops using itemController=)

UPDATE 4:

I've created a JSFiddle that shows what I'm attempting is possible using _subControllers:

http://jsfiddle.net/spA9Q/5/

However, it only works by doing some setup in the route using setupController, which I don't see how I can use in my application (the controller in question cannot be named the same as the model, as it's for one 'mode' of viewing/editing that model using {{render}} and it uses an async hasMany relationship.)

J B J B · Accepted Answer · 2014-03-17T06:55:08

None of the above methods worked (hopefully Buffered Proxy will be fleshed out and officially support/integrated into Ember someday soon, as not saving nested models until buttons are pushed is a common use case) so I wound up with the following in the parent controller, which does the job:

childModels = this.get('child.content.content');

childModels.forEach(function(child) {

    child.rollback(); // or .save()

});

How can I send a message / call a method on all itemController children instances in Ember?

1 Answers