Ember parent-child controller relationship

Question

I'm trying to set up a relationship between a parent ArrayController and a child ObjectController using the 'needs' syntax described in this Ember guide - http://emberjs.com/guides/controllers/dependencies-between-controllers/

When I try to access the controllers object to get a reference to the parent from the child I get a 'controllers object undefined' error. Any help appreciated!

Ember version RC4

Template:

<script type="text/x-handlebars" data-template-name="gigs">
<div> // code simplified
    {{#each controller itemController="gig"}}
        {{#view App.GigView contentBinding="this"}}
            <div class="tile">
                <img {{bindAttr src="photo_url"}} />
                {{#if widgetDisplayed}}
                    // widget view
                {{/if}}
            </div>
        {{/view}}
    {{/each}}
</div>  
</script>

Javascript:

App.GigsController = Ember.ArrayController.extend({
  anyWidgetDisplayed: false,

  isAnyWidgetDisplayed: function() {
      return anyWidgetDisplayed;
  }
});

App.GigController = Ember.ObjectController.extend({
  needs: ["gigs"],
  widgetDisplayed: false,

  displayWidget: function() {
    console.log(controllers.gigs);
    if (!controllers.gigs.isAnyWidgetDisplayed) {
      this.set("widgetDisplayed", true);
    }   
  }
});

Hyder Hyder · Accepted Answer · 2013-06-06T17:27:25

When you use a controller via needs, you should get the controller using the get function,

displayWidget: function() {
    var gigsController = this.get('controllers.gigs')
    console.log(gigsController);
    if (!gigsController.get('isAnyWidgetDisplayed')) {
      this.set("widgetDisplayed", true);
    }   
  }

Alternatively when you use itemController, you need not to use needs to get the parentController, you can use the parentController property

App.GigController = Ember.ObjectController.extend({
  widgetDisplayed: false,

  displayWidget: function() {
    var gigsController = this.get('parentController');
    console.log(gigsController);
    if (!gigsController.get('isAnyWidgetDisplayed')) {
      this.set("widgetDisplayed", true);
    }   
  }
});

Refer: this pull request

Ember parent-child controller relationship

1 Answers