Android Image Drawing (iii) Canvas brush screen problem record _android

When drawing a dynamic diagram in canvas, if a fixed background image is used, only a small sprite is moving!
In this case, you have to redraw the background picture in the frame without frames, making it less efficient! Tried all kinds of methods, and finally failed!
If someone has a good method, can provide a bit, thank you!

Here are some of the ways to share in the process :
1, an article about the picture redraw, but only applies to the Genie in fixed position changes, the background is unchanged!
If you use a moving sprite, it will make the entire screen full of sprites moving pictures, bugs.
Address: Android Surfaceview drawing overlay Refresh and Dirty Rectangle Refresh method

2, about Suffaceview and other knowledge, canvas = Sfh.lockcanvas (), and Sfh.unlockcanvasandpost (canvas), the canvas is constantly drawing up, so you need to overwrite the redraw can!
Reference: Surfaceview,surfaceholder,surfaceholder.callback

3, tried to try the layer method, but Canvas.savelayer () method also do not know what meaning!

4, transparent drawing, also do not know how!
This article is just a note, not a solution ...