Ole Begemann has created an interesting control for creating non-rectangular shaped buttons, OBShapedButton. Although UIButton can use images of various shapes, one key benefit of OBShapedButton is that a button of this type will only respond to touches in the areas of the button image that is visible.
The demo project included shows how OBShapedButton differs from a standard button, as the figure below indicates:
OBShapedButton also supports complex image shapes:
Download OBShapedButton
You can download OBShapedButton from github.
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