This is part of my component's template:

{{#each displayResults}}
  <li {{action addSelection this}} {{bindAttr class=\":result active\"}}>
  {{#if controller.template}}
    {{yield}}
  {{else}}
    <span class=\"result-name\">{{displayHelper controller.searchPath}}</span>
  {{/if}}
  <\/li>
{{/each}}

I want the user to be able to customise the html that is used to display the results.

The problem is that the {{yield}} is called while in an {{#each}} helper and if the component is declared like this:

{{#auto-suggest source=controller.employees destination=controller.chosenEmployees}}
<span class=\"result-name\"><img src="img/small_avatar.png"/>{{fullName}}</span>
{{/auto-suggest}}

Then the block between the {{#auto-suggest}} does not have the context of the {{#each}} helper in the component.

Is there anything I can do or is this just the way it is?

This is part of my component's template:

{{#each displayResults}}
  <li {{action addSelection this}} {{bindAttr class=\":result active\"}}>
  {{#if controller.template}}
    {{yield}}
  {{else}}
    <span class=\"result-name\">{{displayHelper controller.searchPath}}</span>
  {{/if}}
  <\/li>
{{/each}}

I want the user to be able to customise the html that is used to display the results.

The problem is that the {{yield}} is called while in an {{#each}} helper and if the component is declared like this:

{{#auto-suggest source=controller.employees destination=controller.chosenEmployees}}
<span class=\"result-name\"><img src="img/small_avatar.png"/>{{fullName}}</span>
{{/auto-suggest}}

Then the block between the {{#auto-suggest}} does not have the context of the {{#each}} helper in the component.

Is there anything I can do or is this just the way it is?

• javascript
• ember.js

2 Answers 2

UPDATE

Now that ember 1.10 has landed, a new syntax was introduced called block params. So there is no need to override the _yield method. For instance inside of your component's template you do:

<ul>    
  {{#each item in source}}
    <li>
    {{! the component is being used in the block form, so we yield}}
    {{#if template.blockParams}}
      {{yield item}}
    {{! no block so just display the item}}
    {{else}}
      {{item}}
    {{/if}}
    </li>
  {{/each}}
</ul>

And then when using the component you get the params passed to {{yield}} using as |var|

{{! no block, the component will just display the item}}
{{auto-suggest source=model as |item|}}

{{! in the block form our custom html will be used for each item}}
{{#auto-suggest source=model as |item|}}
  <h1>{{item}}</h1>
{{/auto-suggest}}

Simple live example

Of course, you can yield any variables using {{yield name age occupation hobbies}} and catch them in the component with:

{{#x-foo user=model as |name age occupation hobbies|}}
  Hi my name is {{name}}, I am {{age}} years old. Major of the times I am {{occupation}}, but also love to {{hobbies}}.
{{/x-foo}}

FOR OLD VERSIONS

You can override the default _yield method, of Ember.Component, and change the context: get(parentView, 'context') to context: get(view, 'context').

App.AutoSuggestComponent = Ember.Component.extend({
  _yield: function(context, options) {      
    var get = Ember.get, 
    view = options.data.view,
    parentView = this._parentView,
    template = get(this, 'template');

    if (template) {
      Ember.assert("A Component must have a parent view in order to yield.", parentView);      
      view.appendChild(Ember.View, {
        isVirtual: true,
        tagName: '',
        _contextView: parentView,
        template: template,
        context: get(view, 'context'), // the default is get(parentView, 'context'),
        controller: get(parentView, 'controller'),
        templateData: { keywords: parentView.cloneKeywords() }
      });
    }
  }
});

Based on Marcio Junior's answer, you can augment _yield without recreating the entire function. Though instead of transparently changing the behaviour of _yield, i would recommend adding an option to your component. E.g.,

 {{#whatever-component useComponentContext=true}}

And in your component's JavaScript file:

  // duck-punch _yield to use the current view
  _yield: function(content, options) {
    var oldParentView = this._parentView;

    if (this.get('useComponentContext')) {
      // temporarily set _parentView to the view we want
      this.set('_parentView', options.data.view);

      // expose the original context via `_parent`
      options.data.view.get('context').set('_parent', oldParentView.get('context'));
    }

    // call the built-in _yield like normal
    var result = this._super.apply(this, arguments);

    // restore _parentView
    this.set('_parentView', oldParentView);

    return result;
  }

With this, something like

{{!-- whatever-component.hbs --}}
{{#each something in somethings}}
  <div {{bind-attr title=something.id}}>
    {{#with something}}
      {{yield}}
    {{/with}}
  </div>
{{/each}}

{{!-- some-view.hbs --}}
{{#whatever-component.hbs}}
  <h1>{{id}}</h1>
  <p>{{someField}}</p>
  <div>{{_parent.theContextTheComponentIsBeingRenderedIn}}</div>
{{/whatever-component.hbs}}

will work as expected