title: setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key Using UICollectionView
body: <p>I have a UICollectionView populated with cells that has a custom class, every cell has 3 labels an image and I just added a button, Before adding the button Everything was working fine, now that I added the button and connected it to the custom cell class (where I connected also the labels and image) The app crashes when populating the UICollectionView.
  On the connection inspectors the button has only the Outlet that connects him to the custom cell class (like the other elements) so Why does the app crashes?
  This is my header file:</p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  
  
  @interface CollectionViewCell : UICollectionViewCell
  @property (weak, nonatomic) IBOutlet UIButton *TestButton; //this one is the button that causes the crash
  @property (weak, nonatomic) IBOutlet UILabel *titleP;
  @property (weak, nonatomic) IBOutlet UILabel *price;
  @property (weak, nonatomic) IBOutlet UILabel *codeP;
  @property (weak, nonatomic) IBOutlet UIImageView *img;
  
  @end
  </code></pre>
  
  <p>EDIT:
  I don't know what happend with the StoryBoard but I just had to clean the project and everything worked fine, thanks all for the help.</p>