how can i detect the touch event of an UIImageView

A UIImageView is derived from a UIView which is derived from UIResponder so it's ready to handle touch events. You'll want to provide the touchesBegan, touchesMoved, andtouchesEnded methods and they'll get called if the user taps the image. If all you want is a tap event, it's easier to just use a custom button with the image set as the button image. But if you want finer-grain control over taps, moves, etc. this is the way to go.

You'll also want to look at a few more things:

• Override canBecomeFirstResponder and return YES to indicate that the view can become the focus of touch events (the default is NO).

• Set the userInteractionEnabled property to YES. The default for UIViews is YES, but forUIImageViews is NO so you have to explicitly turn it on.

• If you want to respond to multi-touch events (i.e. pinch, zoom, etc) you'll want to setmultipleTouchEnabled to YES.