When we run the emulator that comes with Android Studio. The screen may keep flickering (as shown below), which is extremely harmful to our eyes (barely bearable, but as an obsessive-compulsive disorder, it cannot be tolerated!!!)
Although it can be solved, I still don’t know why, it’s a bit mysterious!
At this time, we only need to set up the simulator and click this little pencil
Then the following interface appears:
Change "Automatic" in Graphics to "Software - GLES 2.0", then restart the simulator to solve the screen flickering problem!
but! ! ! !
Some people will find that the Graphics of their simulator cannot be changed. Why?
This is because Google Play Images running on devices such as Pixel or Nexus 5(x) can only accept automatic graphics acceleration. To put it simply, when we create a simulator, as long as the selected simulator has the 
flag, the Graphics cannot be changed, so there may be a screen flicker that cannot be solved.
Then you can only change the simulator!
Done! Respect!