iOS 项目整体是竖屏个别页面支持横屏

最近在做一个视频APP，工程整体是竖屏的，如下图，播放器需支持横屏。在转屏的过程遇到很痛苦的问题。[UIApplication sharedApplication].statusBarOrientation = self.UIInterfaceOrientationLandscapeLeft; 未生效设置完后，还是UIInterfaceOrientationPortrait。查阅资料是UITabbarController的方法- (BOOL)shouldAutorotate没有返回NO。这是因为当UIviewController方法- (BOOL)shouldAutorotate 返回值为YES的时候是不生效的。

我遇到的问题如图：从横屏到竖屏有个停顿，然后再竖过来。并且statusbar也没转过来。

下面介绍一下如何做到“iOS 项目整体是竖屏，个别页面支持竖屏”，需要以下几步：

1.工程设置为Portrait，如第一张图

2.在appdelegate中实现方法：- (UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window 如下：

- (UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {VideoPlayerViewController* videoPlayerVC = [VideoPlayerViewController defaultVideoPlayerViewController];if ([VideoPlayerViewController isBeingShowed]&& VideoPlayerViewModeFullscreen == videoPlayerVC.viewMode&& !videoPlayerVC.presentedViewController&& !videoPlayerVC.isVideoPlayerDestroying){return UIInterfaceOrientationMaskLandscape;/*在需要横屏的controller显示的时候返回横屏，其他页面返回竖屏*/}return UIInterfaceOrientationMaskPortrait;/*其他页面返回竖屏*/}

3.现在APP普遍使用tab模式。所以还需要在UITabbarController和UINavigationController。这是因为需要横屏的UIViewController一半在UINavigationController上，而UINavigationController又在tabbar上，tabbar又在window上。这一系列都要实现才行。UITabbarController可以直接重写- (BOOL)shouldAutorotate，不在累赘

下面是UINavigationController的分类。

@implementation UINavigationController (Rotation) - (BOOL)shouldAutorotate { return [[self.viewControllers lastObject] shouldAutorotate]; } - (NSUInteger)supportedInterfaceOrientations { return [[self.viewControllers lastObject] supportedInterfaceOrientations]; } - (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation { return [[self.viewControllers lastObject] preferredInterfaceOrientationForPresentation]; } @end

4.在VideoPlayerViewController中实现- (BOOL)shouldAutorotate{}，在需要横屏的情况返回yes，其他情况返回NO。方法和- (UIInterfaceOrientationMask)supportedInterfaceOrientations{}，

5.一般视频的转横屏都是新开一个window叫playerWindow。将视频的VideoPlayerViewController的view添加到playerWindow上。转竖屏时候再将playerWindow置位nil。VideoPlayerViewController.view再恢复到原始的window之上。简要代码如下：

/*转为竖屏时候需要回复原始window*/- (void)removeModelPlayerViewController {[self removeModelPlayerNotification];UIWindow* playerWindow = self.playerWindow;if (playerWindow) {VideoPlayerViewController* videoPlayerVC = self.videoPlayerViewController;videoPlayerVC.view.transform = CGAffineTransformIdentity;videoPlayerVC.view.frame = self.bounds;videoPlayerVC.videoPlayerView.frame = self.bounds;[self addSubview:videoPlayerVC.view];[self.originWindow makeKeyAndVisible];playerWindow.hidden = YES;playerWindow.rootViewController = nil;[playerWindow removeAllSubviews];self.playerWindow = nil;self.originWindow = nil;}}/*横屏时候，开一个window，并makeKeyAndVisible*/- (void)registerPlayerWindow {if (nil == self.playerWindow) {self.originWindow = [[[UIApplication sharedApplication] delegate] window];CGRect frame = [UIScreen mainScreen].bounds;// 交换长宽,解决iOS8+window尺寸bugif (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"8") && frame.size.width < frame.size.height) {frame.size.width = frame.size.width+frame.size.height-(frame.size.height = frame.size.width);}UIWindow* tmpWindow = [[UIWindow alloc] initWithFrame:frame];self.playerWindow = tmpWindow;tmpWindow.backgroundColor = [UIColor clearColor];tmpWindow.windowLevel = UIWindowLevelNormal;VideoPlayerViewController* videoPlayerVC = self.videoPlayerViewController;tmpWindow.rootViewController = videoPlayerVC;videoPlayerVC.view.frame = tmpWindow.bounds;videoPlayerVC.view.backgroundColor = [UIColor clearColor];[tmpWindow addSubview:videoPlayerVC.view];[tmpWindow makeKeyAndVisible];self.originOrientation = [[UIApplication sharedApplication] statusBarOrientation];}}

出了上面这些，你还需要实现旋转动画。看起来才舒服一些。