Output iPad content to external display

Question

I've heard it's possible to output content from an iPad app to an external display, but the app has to be prepared for this and there are serious limitations. Any pointers?

And also, can this be done for iPhone? Is it the same?

Answer 1

As little indicates, you'll need to create a new UIWindow and attach it to the UIScreen for the external display. This UIWindow will host the content to be presented on the external display, so you'll need to build a distinct view hierarchy for that, separate from your main application interface. You also will need to listen for the UIScreenDidConnectNotification and UIScreenDidDisconnectNotification notifications that inform your application when the external display has been attached and removed.

I demonstrate how to do this in the video for the iPad session of my class on iTunes U, for which the course notes can be viewed here.

Matt Gemmell also did a very nice writeup on this recently, which you can read here.