How to simulate sleep mode on Android emulator

Try the following on emulator

1. Go to Settings
2. Go to Developer options
3. Un-check Stay awake (3rd option from the top)

The emulator will go to sleep after 1 min (default setting) if not changed.

Press the power button to wake up the emulator.

Developer options is not enabled by default, to enable it, do the following:

1. Go to Settings
2. Click About emulated device
3. Click Build number 7 times, you should be notified that Developer options is now enabled
4. Go back and you should see Developer options