How to know the current scale of a UIView?

ios objective-c uiview zoom scale
Jonathan picture Jonathan · Aug 20, 2012 · Viewed 15.1k times · Source

How do you find the current scale (zoom level) of a UIView?

Answer

Tim picture Tim · Aug 20, 2012

If you're applying a scale transform to your view, that transform will be available (appropriately enough) through the transform property on UIView. According to the CGAffineTransform docs, scale transforms will have nonzero values at coordinates (1,1) and (2,2) in the transform matrix; you can therefore get your x- and y-scale factors by doing:

CGFloat xScale = view.transform.a;
CGFloat yScale = view.transform.d;

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