Get size of IBOutlet UIImageView

I need to get the size of an IBOutlet UIImageView drawn in Interface Builder.

But if I read the IBOutlet UIIMageView.image.size.width or .height in the viewDidLoad, viewWillAppear or view开发者_Go百科DidAppear method I always get 0 !!!

Where (which method) and how (may be an other variable ?) can I get this information ?

Thank you for your help

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does

UIImageView *iv;  
width = iv.frame.size.width;

work any better? Instead of the image, get the size of the UIImageView.

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You will get the size value, if "Use Autolayout" option in file inspector is unchecked