iOS 6 時代の画面の回転の話

iOS SDK Release Notes for iOS 6 の中に画面の回転について記述がある。
かなり長くなるけど引用。

• iOS SDK Release Notes for iOS 6

・Autorotation is changing in iOS 6. In iOS 6, the shouldAutorotateToInterfaceOrientation: method of UIViewController is deprecated. In its place, you should use the supportedInterfaceOrientationsForWindow: and shouldAutorotate methods.
    More responsibility is moving to the app and the app delegate. Now, iOS containers (such as UINavigationController) do not consult their children to determine whether they should autorotate. By default, an app and a view controller’s supported interface orientations are set to UIInterfaceOrientationMaskAll for the iPad idiom and UIInterfaceOrientationMaskAllButUpsideDown for the iPhone idiom.
    A view controller’s supported interface orientations can change over time―even an app’s supported interface orientations can change over time. The system asks the top-most full-screen view controller (typically the root view controller) for its supported interface orientations whenever the device rotates or whenever a view controller is presented with the full-screen modal presentation style. Moreover, the supported orientations are retrieved only if this view controller returns YES from its shouldAutorotate method. The system intersects the view controller’s supported orientations with the app’s supported orientations (as determined by the Info.plist file or the app delegate’s application:supportedInterfaceOrientationsForWindow: method) to determine whether to rotate.
    The system determines whether an orientation is supported by intersecting the value returned by the app’s supportedInterfaceOrientationsForWindow: method with the value returned by the supportedInterfaceOrientations method of the top-most full-screen controller.
    The setStatusBarOrientation:animated: method is not deprecated outright. It now works only if the supportedInterfaceOrientations method of the top-most full-screen view controller returns 0. This makes the caller responsible for ensuring that the status bar orientation is consistent.
    For compatibility, view controllers that still implement the shouldAutorotateToInterfaceOrientation: method do not get the new autorotation behaviors. (In other words, they do not fall back to using the app, app delegate, or Info.plist file to determine the supported orientations.) Instead, the shouldAutorotateToInterfaceOrientation: method is used to synthesize the information that would be returned by the supportedInterfaceOrientations method.

拙作「ねむスタ」では４つあるタブのうち１つのタブだけで画面を回転させられるようにしていたのだけど、この変更の影響でどのタブでも回転してしまうようになってしまった。

慌てて修正してなんとか iPhone 5 リリース当日の朝に iPhone 5 対応の修正バージョンを公開することができたので、画面の回転について簡単にメモ。

とわ言っても、まだ良くわかっていない部分も多いので、もっと詳しい人にあれこれ突っ込んでいただけると嬉しいのだけど…。