如何在設備旋轉過程中「鎖定」視圖的方向

Question

比方說，我有一個視圖控制器，稱之爲ViewControllerPortrait，它被設計爲只能在肖像模式下顯示。例如： -

當用戶旋轉設備的風景，我不想ViewControllerPortrait永遠重新定位自己的風景，但我想提出一個新的全屏視圖。我們稱之爲全屏視圖控制器ViewControllerLandscapeFull。例如：

我再也不想看到的是這樣的：

我試圖做到這一點的方法是讓窗口的RootViewController的存在ViewControllerLandscapeFull在當屏幕全屏時willRotateToInterfaceOrientation:duration:

[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationSlide]; 
[navigationViewController setNavigationBarHidden:YES animated:YES]; 

self.viewControllerPortrait = [[ViewControllerPortrait alloc] init]; 
self.viewControllerPortrait.modalPresentationStyle = UIModalPresentationFullScreen; 
[self presentViewController:self.viewControllerPortrait animated:NO completion:NULL]; 

然後在ViewControllerLandscapeFull我：

- (NSUInteger)supportedInterfaceOrientations 
{ 
    return UIInterfaceOrientationMaskLandscape | UIInterfaceOrientationMaskPortrait; 
} 

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation 
{ 
    return (UIInterfaceOrientation)[UIDevice currentDevice].orientation; 
} 

這工作得相當好。由於ViewControllerLandscapeFull「更喜歡」風景，並具有UIModalPresentationFullScreenmodalPresentationStyle，它只能在風景中顯示。通過爲supportedInterfaceOrientations返回landscape | portrait，設備旋轉回肖像被允許發生ViewControllerLandscapeFull得到willRotateToInterfaceOrientation:duration:並最終調用dismissViewControllerAnimated:NO。

我唯一的問題是，在旋轉回肖像期間，您可以暫時看到橫向的ViewControllerPortrait，這就是我想要避免的。

ViewControllerPortrait確實實現：

- (NSUInteger)supportedInterfaceOrientations 
{ 
    return UIInterfaceOrientationMaskPortrait; 
} 

而且我驗證過的UIKit是調用它，但它似乎沒有任何效果。 （該文檔說，supportedInterfaceOrientations只在根視圖控制器和視圖控制器呈現全屏，所以我實際上很驚訝UIKit稱之爲。）

FWIW，我正在與iOS 8 beta 5 SDK並建設7/8。

Muchas gracias。

Answer 1

我剛剛開始使用iPhone編程，但也許這將工作...

點擊您的項目文件>部署信息。然後，除了肖像以外，請取消選中所有內容這樣旋轉設備將不會重新定位自己。

但是，你仍然可以測試設備是否旋轉或不符合本：

- (BOOL)shouldAutorotate 
{ 
    if (UIDeviceOrientationIsLandscape([UIDevice currentDevice].orientation)) 
    { 
     NSLog(@"ROTATE to landscape"); 
     kitty.hidden = NO; 
     //(kitty is my imageview, hidden on load), once the device rotates to landscape, you can show your image.(or you can do something else) 
    } 
    else{ 
     NSLog(@"ROTATE to portrait"); 
     kitty.hidden = YES; 
    } 
    return YES; 
} 

Answer 2

houldAutorotate, supportedInterfaceOrientations, preferredInterfaceOrientationForPresentation 

上述方法不會被調用一個視圖 - 控制的，如果他們是navigationcontroller的任何tabbarcontroller內。如果這些方法在tabbarcontroller或導航控制器內部聲明，那麼它們將被調用。在我的例子中，viewcontrollers在navigationcontroller裏面，導航控制器在tabbarcontroller裏面。

爲了解決這個我做一個類FixedOrientationTab，它是UITabBarController一個子類，導航類OrientationEnabledNavigation，它是UINavigationController一個子類。然後我在FixedOrientationTab和OrientationEnabledNavigation內實施shouldAutorotate,supportedInterfaceOrientations,preferredInterfaceOrientationForPresentation方法。

OrientationEnabledNavigation.h

#import <UIKit/UIKit.h> 

@interface OrientationEnabledNavigation : UINavigationController 

@end 

OrientationEnabledNavigation.m

#import "OrientationEnabledNavigation.h" 

@interface OrientationEnabledNavigation() 

@end 

@implementation OrientationEnabledNavigation 

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 
{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 
     // Custom initialization 
    } 
    return self; 
} 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view. 
} 

- (BOOL)shouldAutorotate 
{ 
    return [self.topViewController shouldAutorotate]; 
// return NO; 
} 

- (NSUInteger)supportedInterfaceOrientations 
{ 
    return [self.topViewController supportedInterfaceOrientations]; 
} 

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation 
{ 
    return [self.topViewController preferredInterfaceOrientationForPresentation]; 
} 

- (void)didReceiveMemoryWarning 
{ 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

@end 

FixedOrientationTab.h

#import <UIKit/UIKit.h> 

@interface FixedOrientationTab : UITabBarController 

@end 

FixedOrientationTab.m

#import "FixedOrientationTab.h" 

@interface FixedOrientationTab() 

@end 

@implementation FixedOrientationTab 

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 
{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 
     // Custom initialization 
    } 
    return self; 
} 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view. 
} 

- (BOOL)shouldAutorotate 
{ 
    return [self.selectedViewController shouldAutorotate]; 
    // return NO; 
} 

- (NSUInteger)supportedInterfaceOrientations 
{ 
    return [self.selectedViewController supportedInterfaceOrientations]; 
} 

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation 
{ 
    return [self.selectedViewController preferredInterfaceOrientationForPresentation]; 
} 


- (void)didReceiveMemoryWarning 
{ 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

@end 

然後，如果你想在你的項目中使用導航控制器，然後使用OrientationEnabledNavigation和的TabBar FixedOrientationTab。之後，如果您在viewcontroller中執行shouldAutorotate，supportedInterfaceOrientations，preferredInterfaceOrientationForPresentation這些方法，那麼它們將被調用。

希望這會有所幫助.. :)