How to make SurfaceView's background transparent without using function setZOrderOnTop(true)?

I'm programming a turntable game view by LuckyPan from github. As you see, it extends a SurfaceView.

And here is my problem:

1. I need a background below turntable with picture, it means I need a SurfaceView which has a transparent background;
2. setZOrderOnTop(true) — I found it to make a transparent background, but it made SurfaceView above everything in the APP;
3. Now when I run app in a short phone, the turntable will above the "bottom tab" which is at the bottom of the screen.

So, does anyone has a way can do one of these: Make SurfaceView have a transparent background without using setZOrderOnTop(true).

OR

Set a view above the SurfaceView which have already calling setZOrderOnTop(true).

Is this a bug of the SurfaceView that always has a not transparent background unless using the setZOrderOnTop(true)? If it is, why google hasn't fix it for more than ten years? Or is there something I missed? Thanks for helping.