In google's structure, lock screen is not a activity but a view. Now i want to make a new lock screen with OpenGL, so i modified the original lock screen in framework, and add a SurfaceView to the original layout "xml" file. And here comes the problem, the SurfaceView is invisible and the other views are visible.

If i called "setZOrderOnTop(true)", then the SurfaceView will be visible, but there may be overlapping. For example, if i make a soft keyboard visible before i lock screen, then the keyboard will overlap the lock screen. And also, if a call is incoming, the incoming call view will overlap the lock screen, that's terrible.

How could i make the SurfaceView visible with out changing its Z-Order?

My English is poor, hope i make myself clear.Thanks a lot.
And also, i don't know whether it's correct to make it here, should i post it in "View, Layout & Resource Problems"?