将子视图添加到UIImageView，它是IB中UIViewController的视图出口

Question

I have a UIViewController object in a .xib file. I add a UIImageView to it, and then try to add a button as a subview of the UIImageView. It instead replaces the UIImageView. It works fine if both are subviews of a UIView. What gives? I thought this would work since UIImageView is a subclass of UIView?

Answer 1

Only Apple knows.

However, look at here for a workaround:

Apple Interface Builder: adding subview to UIImageView

Answer 2

A UIImageView is it's own object and a UIButton is its own object. A UIImageView is an outlet placeholder for an image. If you're trying to add a background image to a button you can use the background image property or if you'd like the background to span beyond the bounds of the button you can drop a UIView onto IB and style that using code or subclassing UIImageView .