1. When I didn't run the android program once before, I would close the AVD (that is, the phone that pops up after you click to run the android program!), and then open it again when I want to run the next program, which takes a while . Later, I found out that, in fact, the mobile phone interface can be closed, so that when you run the next Android program, you do not need to restart the phone and wait for the system to start. When it is detected that the AVD is running, the program will be installed directly into the phone through adb, and then run! ! ! ! !