desktopdisplaymacos
I have connected two external displays to a Macbook and have deselected 'Mirror Displays'. The lid of the Macbook is closed, therefore I am using just the larger screens. The contents of my desktop are currently only shown on screen 2.
However, I would like to tell the OS to not show the contents of the Desktop on screen 2, but on screen 1. How can I achieve that?
Sorry, if this is a duplicate, I couldn't find any question about the desktop contents.
In Quicktime Player, go to Preferences. Under "Full Screen", there is a picture of your screens similar to the Displays pane of System Preferences. If you click on a screen, a picture of the QT Player logo will be overlaid on that screen. The screen that has the logo is the active screen for Full Screen Mode.
EDIT: I don't know if you can still do other things while QT Player is full screen.
I've taken up olivier's suggestion to arrange my monitors to eliminate a common border:
I chose the bottom right because I keep my dock on the left hand side of my screen, and I use my upper right as a hot corner to sleep the display. I also moved the menu bar to my desktop monitor and the MacBook screen is completely dimmed.
There was another option I heard about: using a magnet to make your MacBook think that the lid was closed. This does work - I placed a snippet of a refrigerator magnet near the bottom left side of my keyboard and sure enough my MacBook thought I had closed the display. Unfortunately, Mac OS X also disables keyboard and trackpad input when it thinks the display is closed, so this option didn't work for me.
Best Answer
In my experience for Mountain Lion, determining which display is the primary display is usually achieved by dragging the white Menu Bar (circled in screenshot below) onto the graphic of another display, thus setting the other display as the primary monitor.