When the UISupportedInterfaceOrientations key is missing, iOS will start
up the application in the orientation defined by UIInterfaceOrientation,
and if that key is also missing, it will default to portrait orientation.
Unfortunately, when the application has finished launching on an iPad,
there is no way to re-evaluate the current device orientation unless the
user actively rotates the device, so for example if the device is physically
in landscape orientation, and the application is started up in portrait,
the application will not auto-rotate to landscape after starting up.
It would seem that [UIViewController attemptRotationToDeviceOrientation]
would be the right API to do this, but even after telling the device
to beginGeneratingDeviceOrientationNotifications the device orientation
will still match the startup orientation until the device is physically
rotated. For iPod/iPhones this is not an issue, as the OS will update
the device orientation after startup. Presumably the difference in
behavior between the two device classes is due to the iPad supporting
any orientation for the application grid.
Since we would prefer the application to either start up in the right
orientation directly, or at least rotate to it after startup, and the
latter can't be done, we apply UIInterfaceOrientationMaskAll to the
Info.plist file. This also has the benefit that the application will
show any splash screens in the right orientation.
Change-Id: If0421bc7b82b7f14a510fa1f34eac4f6407f570f
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@digia.com>
1126efed7d