Android : Place Controls At Absolute Positions - Custom ViewGroup

I have a custom ViewGroup. The idea is to be able to place controls at absolute positions and then have the ViewGroup scale those controls based on the difference in the screen dimensions with respect to the original design dimensions. I am using the code below. In response to the 'onMeasure' message, I am storing the width and height of the view. Then on the 'onLayout' message I am computing new dimensions for the child controls and adjusting their sizes proportionally. This all works to some degree. However for certain controls (e.g. button controls), the control resizes, but the text inside does not remain centered within the control. I am thinking that there is some other call I need to make to update the child controls after I change their size.