问题
set a UIImageView.image property to a UIImage is unable add the image to the view,however if i set the imageview frame property,it works.can anyone tell me how it's happen? and what will happen when i apply the UIImage instance method[drawInRect:] redraw the image frame which is larger than the view frame?i have tried but nothing happen,and what is this function doing actual?
回答1:
Generally, how it works is, you add an Image to a UIImageView and then add the UIImageView to a UIView to display it on the screen. You can do this programmatically, or using Interface Builder. Optionally, you can create a CGRect (based on a frame, if you like), use this as the bounds for the UIImageView (or you can frame the UIView). There are several ways to do what you want to do.
It's hard to tell without seeing your code. It could be a number of things. You could be inserting the view with the image behind the currentView? You may not be retaining the UIImageView. We can't read minds here necessarily, (sometimes we do). But you'll need to be more helpful if you want a solid answer.
Or just take a look at this:
UIImageView Docs
来源：https://stackoverflow.com/questions/680109/uiimage-and-uiimageview-problem