Why didInsertElement hook trigger before elements rendered inside {{#each}} block? - ember.js

Question

I'm new to Ember, I want to add some query DOM manipulation code to the element in the {{#each}} block. So I google it up and found the solution from this guide:
views/products/index.js
import Spinner from 'appkit/utils/someJqueryCode';
Ember.View.reopen({
didInsertElement : function(){
this._super();
Ember.run.scheduleOnce('afterRender', this, this.afterRenderEvent);
},
afterRenderEvent : function(){
// implement this hook in your own subclasses and run your jQuery logic there
}
});
export default Ember.View.extend({
afterRenderEvent: function() {
Spinner();
}
});
templates/products/index.hbs
<div class='panel panel-default products'>
<div class='panel-heading'>
<h2 class='panel-title'>Our Prodcuts</h2>
</div>
<div class='panel-body'>
<ul class='row'>
{{#each}}
<li class='col-md-4'>
<div class='thumbnail'>
<img {{bind-attr src=url alt=alt}} />
</div>
<div class='caption'>
<h3 class='name-me'>{{name}}</h3>
<p>{{description}}</p>
<div class='row no-gutter'>
<div class='col-xs-3'>
<button class='btn btn-primary'>Buy</button>
</div>
</div>
</div>
</li>
{{/each}}
</li>
</div>
</div>
But I seems after the point when afterRenderEvent() is triggered, all the elements in the {{#each}} block hasn't been rendered to the DOM yet, thus, the jQuery code return undefined
What's the right way to do it?

Answer 1

Your view's didInsertElement hook will fire as soon as the application route is rendered, which happens before the index route. You might think that putting it in the index.js file will work, but it's going to just extend the default application view behavior.
You need to create a more focused view that lives within your index.hbs file. One that is only concerned with your spinner jQuery doohickey. That, and an each/else conditional could work nicely here. For example:
{{#each}}
{{#view App.SpinnerDoohickeyView}}
<li class='col-md-4'>
<div class='thumbnail'>
<img {{bind-attr src=url alt=alt}} />
</div>
<div class='caption'>
<h3 class='name-me'>{{name}}</h3>
<p>{{description}}</p>
<div class='row no-gutter'>
<div class='col-xs-3'>
<button class='btn btn-primary'>Buy</button>
</div>
</div>
</div>
</li>
{{/view}}
{{else}}
<li>Empty collection!</li>
{{/each}}
Notice that I've wrapped each list item in its own view. You could wrap the whole ul if you wanted... this is just an example. The idea is that you are only creating views when you have a model.
And now you can define the view, and simply use the didInsertElement hook to work with jQuery:
App.SpinnerDoohickeyView = Ember.View.extend({
didInsertElement: function () {
this.$('li').css('background', 'blue');
}
});
If you have a model to render, jQuery should be able to safely access it this way. Good luck!
Here's some further reading and some code from the Ember folks that looks like what I've shown you here: http://emberjs.com/guides/views/handling-events/