adding a layer mask to UIToolBar/UINavigationBar/UITabBar breaks translucency <p>Im upgrading my UI to iOS 7, and have been using a custom tab bar which has a CAShapeLayer used as a mask. Ive been trying to add dynamic blur by having a UIToolBar underneath, but if i try setting the layer.mask property on the toolbar translucency is gone, and i just have it semi transparent (but masking works of course). Is there a way to get this working? Ive also seen this behavior when adding a subview to these classes.</p>