UIView

Returns the first responder or nil if nothing is currently first responder.

Returns a list of all the receiver’s subviews, computed recursively.

Returns the receiver’s owning view controller or if it cannot be found.

Adds the provided subviews to the receiver.

Removes all the receiver’s subviews.

Starts a shake animation that will last duration seconds.

Stops any in progress shake animation.

Returns the first view of class walking up the view hierarchy or nil if one cannot be found.