add a collection view controller to another controller as subview
<p>I am trying to add a <code>collectionViewController</code> to another controller as subview.</p>

<p><code>datasource</code> and <code>delegate</code> methods are called.</p>

<p>I can interact with the cells i.e, I can call <code>didSelectItemAtIndexpath</code>, but i can't see anything.</p>

<p>Please let me know if I did anything wrong.</p>

<pre><code> HairTypeFilterController *htfvc=[self.storyboard instantiateViewControllerWithIdentifier:@"hairTypeFilterSBID"];

[self addChildViewController:htfvc];

[htfvc didMoveToParentViewController:self];

htfvc.view.frame=CGRectMake(0, 0, _filterDetailsOutlet.frame.size.width, _filterDetailsOutlet.frame.size.height);
[_filterDetailsOutlet addSubview:htfvc.collectionView];
</code></pre>