I'm working on building a UICollectionView subclass to cover up more convenient layouts in a simple way. It needs to have another delegate property to handle messages from custom UICollectionViewLayout class, which the UICollectionView class already has, so I wish the delegate property of UICollectionView handles both UICollectionViewDelegate and another custom delegate protocol.
More specifically, I'd like to build something like the followings.
@interface CPGridCollectionView : UICollectionView <CPGridLayoutDelegate>
// add protocol declaration to existing delegate property
@property (nonatomic, weak, nullable) id<UICollectionViewDelegate, CPGridLayoutDelegate> delegate;
// more additional features
@end
But warning came up as:
Auto property synthesis will not synthesize property 'delegate'; it will be implemented by its superclass, use @dynamic to acknowledge intention
It seems that I need to add attributes to existing property of UICollectionView, without breaking the functionality of UICollectionViewDelegate. Is this possible in Obj-C, and how can this warning be avoided?