Comments by C_ray (Top 1 by date)

// Lastly, set the height of the layout LinearLayout.LayoutParams rootParams = (android.widget.LinearLayout.LayoutParams)root.getLayoutParams();

The above line as I think should be:
FrameLayout.LayoutParams rootParams = (android.widget.FrameLayout.LayoutParams)root.getLayoutParams();

The root view is wrapped in a FrameLayout as defined by android, so the LayoutParams need to be kept in sync with that.