I was the first to explore the program two years ago, and my ambitions set a goal. Then I found out that I can't do it. . . In particular, she is no longer separated. . . I have been learning programming for the past two years, such as the fire storage app in the previous period. Return to this rotten stall two years later, and still pack it up. You have to add oil ! This program is open source software (GNU GPL 3+), you can see the source code here: https://github.com/fei0316/spacing-androi