Monitoring Orientation of Top App
Whenever the orientation of the top application is changed, -[SpringBoard noteUIOrientationChanged:display:] is called. Therefore, you can hook this method to be notified of the event.
You can also hook SpringBoard's -(void)noteInterfaceOrientationChanged:(int)arg1 duration:(float)arg2
activeInterfaceOrientation shows present orientation
interfaceOrientationForCurrentDeviceOrientation shows the device orientation
Q: When will these be different?
A: If you have the device locked in portrait but a game plays in landscape these values will be different. activeInterfaceOrientation will be in landscape while interfaceOrientationForCurrentDeviceOrientation will still be in the locked portrait.
Sending messages to SpringBoard
Because SpringBoard inherits from UIApplication, you can send messages to it as follows: [[SpringBoard sharedApplication] aMethod]
Getting the top SBApplication
A reference to the top SBApplication may be obtained by using the following method: [[SpringBoard sharedApplication] _accessibilityFrontMostApplication].
Monitoring when a new app or the homescreen is displayed
Whenever a different app is displayed, frontDisplayDidChange:(id *)newDisplay is called. newDisplay is a reference to the SBApplication of the displayed app if the app was switched to, or it is nil if the homescreen is now showing. However, in some situations, it may be a reference to a UIViewController. For example, when the lockscreen is shown, newDisplay references an instance of SBLockScreenViewController. Make sure you account this in your tweak.
- Header: http://github.com/kennytm/iphone-private-frameworks/blob/master/SpringBoard/SpringBoard-Class.h