Framelayout of Android Studio

1. The frame layout is equivalent to one piece of paper overlaid on another
2. All controls are displayed on the top left of the screen by default
3. Set the foreground image of the frame layout container below the Framelayout (always on top of all child controls) android :foreground = "a picture or a color"
set the foreground image display position android:foregroundGravity = "left or right or other position"