Unwanted Vertical Padding from iOS 6 on CATextLayer

Question

Background: I started my project in iOS 5 and built out a beautiful button with layer. I added a textLayer onto the button and center it using the following cod

Answer 1

It seems to me that iOS 6 has taken into account the Line Height (or other font related features that affects the actual vertical drawing position of the glyph) of the font when drawing the text contents of CATextLayer. The result is that in iOS 6.0, the text with certain font in CATextLayer is not displayed at the top edge of the frame of the CATextLayer. I found that some font has such vertical padding while others don't. While in iOS 5.0/5.1, the glyph of the text is actually displayed at the top edge of the frame of the CATextLayer.

So one possible solution I'm thinking may be to change the textLayer object in your code from CATextLayer to just CALayer (or subclass CALayer) and use Core Text to custom draw the contents such that you get to control of everything that will be consistent across iOS 5.0/5.1 and 6.0.