iOS 8:以纵向呈现模态视图控制器会导致底层风景导航控制器的导航栏调整大小

Question

在iOS 8上,我对导航栏和方向更改有一个奇怪的行为.

我有一个导航控制器,报告支持的界面方向UIInterfaceOrientationMaskLandscapeRight.导航栏具有预期的横向高度(遗憾的是我无权发布屏幕截图).

然后我启动一个仅支持的视图控制器的模态演示UIInterfaceOrientationMaskPortrait.当演示动画开始时,似乎底层导航控制器的度量被改变为纵向呈现,因为导航栏的高度增长到其肖像大小,如上所述.

iOS 7不会出现此行为.我错过了什么？我想恢复旧的行为.

以下是上述简单示例的完整代码:

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 
{
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];


    DOGButtonViewController *root = [DOGButtonViewController new];
    DOGOrientedNavigationController *navi = [[DOGOrientedNavigationController alloc] initWithRootViewController:root];
    navi.allowedInterfaceOrientations = UIInterfaceOrientationMaskLandscapeRight;

    self.window.rootViewController = navi;

    [self.window makeKeyAndVisible];
    return YES;
}

- (NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window
{
    return UIInterfaceOrientationMaskLandscapeRight | UIInterfaceOrientationMaskPortrait;
}

@end


@implementation DOGOrientedNavigationController

- (NSUInteger)supportedInterfaceOrientations
{
    return self.allowedInterfaceOrientations;
}

@end

@implementation DOGButtonViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.title = @"Button View Controller";
}

- (BOOL)prefersStatusBarHidden
{
    return YES;
}

- (IBAction)buttonClicked:(id)sender
{
    DOGPortraitViewController *vc = [DOGPortraitViewController new];
    [self presentViewController:vc animated:YES completion:nil];
}

@end

@implementation DOGPortraitViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.title = @"Portrait Title";
}

- (NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskPortrait;
}

- (IBAction)buttonClicked:(id)sender
{
    [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
}

- (BOOL)prefersStatusBarHidden
{
    return YES;
}

@end

在更复杂的设置中,我还会在呈现纵向模态时按比例放大导航控制器中包含的UIWebView中的文本.取消模态时,文本不会调整为原始大小.

Answer 1

由于缺乏更好的选择，我为此做了一些修改。基本上，在显示模态视图之前，我会拍摄屏幕截图并将其放在呈现视图控制器的顶部。

显然，当视图重新出现时，我必须删除此屏幕截图

  func showScreenShot () {
    let image = screenShot()
    self.screenShotImageView = UIImageView(image: image)
    self.view.addSubview(self.screenShotImageView!)
  }

func screenShot () -> UIImage {
    UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, true, UIScreen.mainScreen().scale)
    self.view.layer.renderInContext(UIGraphicsGetCurrentContext())
    let image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image
}

func removeScreenShot () {
  if let screenImageView = self.screenShotImageView {
   screenImageView.removeFromSuperview()
   self.screenShotImageView = nil
  }
}