When I close my Macbook Air, the second display goes black.
When I close my Macbook Air, the second display goes black.
I'm assuming that what you want to do is be able to use your Mac while projecting to the secondary display only.
If that's what you want to do, then:
- Go to "System Preferences"
- Select "Battery"
- Select "Power Adapter"
- Set the "Turn display off after:" slider to "Never" (all the way to the right)
- Connect the secondary display
- Close the MacBook lid.
Do not forget to plug your MacBook in, you don't want it to shut down while you're using it due to low batter...