如何将位图叠加在特定XY位置的另一个位图上

I am working on a project where I have used canvas and user can touch move one bitmap overlay to another bitmap. When user presses save button then both bitmaps should merge and become a single bitmap. I have done all things and now merging two bitmap at XY position remains. During my research I found following code. I am working on a project where I have used can