如何知道AppDelegate中的方向已更改

设备如何知道方向变化的function是 – （void）viewWillLayoutSubviews和 – （void）viewDidLayoutSubviews但是，它们只是在控制器中; 现在我想知道是否有这样的函数来了解文件AppDelegate.m中方向的变化

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated { UINavigationBar *morenavbar = navigationController.navigationBar; UINavigationItem *morenavitem = morenavbar.topItem; //We don't need Edit button in More screen. morenavitem.rightBarButtonItem = nil; morenavitem.title = nil; UIImage *backgroundImage = [UIImage imageNamed:@"nav.png"]; [morenavbar setBackgroundImage:backgroundImage forBarMetrics:UIBarMetricsDefault]; UIDeviceOrientation currentDeviceOrientation = [[UIDevice currentDevice] orientation]; UIInterfaceOrientation currentInterfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation]; if (UIDeviceOrientationIsLandscape(currentDeviceOrientation)|| UIDeviceOrientationIsLandscape(currentInterfaceOrientation)){ UIImage *backgroundImageLandscape = [UIImage imageNamed:@"navbar_landscape.png"]; [morenavbar setBackgroundImage:backgroundImageLandscape forBarMetrics:UIBarMetricsDefault]; } } 

Answer 1

您可以在轮换发生时注册通知

 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handleDidChangeStatusBarOrientationNotification:) name:UIApplicationDidChangeStatusBarOrientationNotification object:nil]; 

然后实现在发送消息时调用的方法

 - (void)handleDidChangeStatusBarOrientationNotification:(NSNotification *)notification; { // Do something interesting NSLog(@"The orientation is %@", [notification.userInfo objectForKey: UIApplicationStatusBarOrientationUserInfoKey]); } 

或者查看UIApplicationDidChangeStatusBarOrientationNotification的文档，它将为您提供

Answer 2

如果您正在讨论界面方向，您可以观察UIApplicationDidChangeStatusBarOrientationNotification ，如果您希望在设备方向更改时收到通知，您可以观察UIDeviceOrientationDidChangeNotification