在做視頻開發時遇到屏幕旋轉問題,其中涉及到 StatusBar、 UINavigationController、UITabBarController 、UIViewcontroller
。
在設備鎖屏下的整體效果圖
主要涉及以下4點:
- 橫豎屏的旋轉
- 屏幕旋轉相應改變視圖位置
- 旋轉時狀態欄的隱藏與顯示
- 鎖屏
1、橫豎屏旋轉
-
第1步:
-(UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window { // NSLog(@"0000000---------%@",NSStringFromClass([[self topViewController] class])); // if ([NSStringFromClass([[self topViewController] class]) isEqualToString:@"FirstViewController"]) { // //橫屏 // return UIInterfaceOrientationMaskLandscapeRight; // } // //豎屏 // return UIInterfaceOrientationMaskPortrait; NSUInteger orientations = UIInterfaceOrientationMaskAllButUpsideDown; if(self.window.rootViewController){ //取出當前顯示的控制器 UIViewController *presentedViewController = [self topViewControllerWithRootViewController:self.window.rootViewController]; //按當前控制器支持的方向確定旋轉方向(將旋轉方向重新交給每個控制器自己控制) NSLog(@"%s, line = %d",__FUNCTION__,__LINE__); orientations = [presentedViewController supportedInterfaceOrientations]; } return orientations; } //獲取界面最上層的控制器 //- (UIViewController*)topViewController { // NSLog(@"%s, line = %d",__FUNCTION__,__LINE__); // return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController]; //} //一層一層的進行查找判斷 - (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)rootViewController { NSLog(@"%s, line = %d",__FUNCTION__,__LINE__); if ([rootViewController isKindOfClass:[UITabBarController class]]) { UITabBarController* tabBarController = (UITabBarController*)rootViewController; NSLog(@"Tabbar:%@",NSStringFromClass([tabBarController.selectedViewController class])); return [self topViewControllerWithRootViewController:tabBarController.selectedViewController]; } else if ([rootViewController isKindOfClass:[UINavigationController class]]) { UINavigationController* nav = (UINavigationController*)rootViewController; NSLog(@"nav:%@",NSStringFromClass([nav.visibleViewController class])); return [self topViewControllerWithRootViewController:nav.visibleViewController]; } else if (rootViewController.presentedViewController) { NSLog(@"present:%@",NSStringFromClass([rootViewController.presentationController class])); UIViewController* presentedViewController = rootViewController.presentedViewController; return [self topViewControllerWithRootViewController:presentedViewController]; } else { NSLog(@"root:%@",rootViewController); return rootViewController; } }
代碼中通過 -(UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window
方法將控制器交給自己控制,該方法默認值為Info.plist
中配置的Supported interface orientations
項的值。
-
第2步:在各控制器設置支持的方向
//是否允許旋轉(默認允許) - (BOOL)shouldAutorotate { return YES; } - (UIInterfaceOrientationMask)supportedInterfaceOrientations{ //允許旋轉的方向 return UIInterfaceOrientationMaskAll; }
其中
- supportedInterfaceOrientations
方法在 iPad 中默認取值為UIInterfaceOrientationMaskAll
,即默認支持所有屏幕方向;而 iPhone 跟 iPod Touch 的默認取值為UIInterfaceOrientationMaskAllButUpsideDown
,即支持除豎屏向下以外的三個方向。
在設備屏幕旋轉時,系統會調用- shouldAutorotate
方法檢查當前界面是否支持旋轉,只有- shouldAutorotate
返回YES
的時候,- supportedInterfaceOrientations
方法才會被調用,以確定是否需要旋轉界面。
這個是TabbarController
中設置的,它會影響關聯的UIViewController
的支持方向,需要在UIViewController
中進一步設置//此方法來控制能否橫豎屏 控制鎖屏 - (UIInterfaceOrientationMask)supportedInterfaceOrientations { NSLog(@"%s, line = %d",__FUNCTION__,__LINE__); UIInterfaceOrientationMask inter; if (_lockScreen) { switch (_lockOrientation) { case 1: inter = UIInterfaceOrientationMaskPortrait; break; case 2: inter = UIInterfaceOrientationMaskPortraitUpsideDown; break; case 3: inter = UIInterfaceOrientationMaskLandscapeRight; break; case 4: inter = UIInterfaceOrientationMaskLandscapeLeft; break; default:inter = UIInterfaceOrientationMaskAll; break; } } else { inter = UIInterfaceOrientationMaskAll; } //支持全部方向 return inter; }
-
第3步:強制轉換控制器方向
- (void)setInterOrientation:(UIInterfaceOrientation)orientation { if ([[UIDevice currentDevice] respondsToSelector:@selector(setOrientation:)]) { SEL selector = NSSelectorFromString(@"setOrientation:"); NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:[UIDevice instanceMethodSignatureForSelector:selector]]; [invocation setSelector:selector]; [invocation setTarget:[UIDevice currentDevice]]; int val = orientation; // 從2開始是因為0 1 兩個參數已經被selector和target占用 [invocation setArgument:&val atIndex:2]; [invocation invoke]; } }
這樣就可以完成橫豎屏的切換。
2、屏幕旋轉相應改變視圖位置
這里先擴展UIDeviceOrientation & UIInterfaceOrientation
的知識
-
UIDeviceOrientation
設備的物理方向
UIDeviceOrientation
即我們手持的移動設備的Orientation
,是一個三圍空間,有六個方向,通過[UIDevice currentDevice].orientation
獲取當前設備的方向。typedef NS_ENUM(NSInteger, UIDeviceOrientation) { UIDeviceOrientationUnknown, UIDeviceOrientationPortrait, UIDeviceOrientationPortraitUpsideDown, // Device oriented vertically, home button on the top 豎屏向下,即頭在下,Home 鍵在上 UIDeviceOrientationLandscapeLeft, // Device oriented horizontally, home button on the right 橫屏頭在左,Home鍵在右 UIDeviceOrientationLandscapeRight, // Device oriented horizontally, home button on the left 橫屏頭在右,Home鍵在左 UIDeviceOrientationFaceUp, // Device oriented flat, face up UIDeviceOrientationFaceDown // Device oriented flat, face down } ;
-
UIInterfaceOrientation
界面的顯示方向
UIInterfaceOrientation
即我們看到的視圖的Orientation
,可以理解為statusBar
所在的方向,是一個二維空間,有四個方向, 通過[UIApplication sharedApplication].statusBarOrientation
即狀態欄的方向獲取當前界面方向。// Note that UIInterfaceOrientationLandscapeLeft is equal to UIDeviceOrientationLandscapeRight (and vice versa). // This is because rotating the device to the left requires rotating the content to the right. typedef NS_ENUM(NSInteger, UIInterfaceOrientation) { UIInterfaceOrientationUnknown = UIDeviceOrientationUnknown, UIInterfaceOrientationPortrait = UIDeviceOrientationPortrait, UIInterfaceOrientationPortraitUpsideDown = UIDeviceOrientationPortraitUpsideDown, UIInterfaceOrientationLandscapeLeft = UIDeviceOrientationLandscapeRight, UIInterfaceOrientationLandscapeRight = UIDeviceOrientationLandscapeLeft }
-
UIInterfaceOrientationMask
支持的方向// iOS 6 之后用于控制界面的枚舉值 typedef NS_OPTIONS(NSUInteger, UIInterfaceOrientationMask) { UIInterfaceOrientationMaskPortrait = (1 << UIInterfaceOrientationPortrait), UIInterfaceOrientationMaskLandscapeLeft = (1 << UIInterfaceOrientationLandscapeLeft), UIInterfaceOrientationMaskLandscapeRight = (1 << UIInterfaceOrientationLandscapeRight), UIInterfaceOrientationMaskPortraitUpsideDown = (1 << UIInterfaceOrientationPortraitUpsideDown), UIInterfaceOrientationMaskLandscape = (UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight), UIInterfaceOrientationMaskAll = (UIInterfaceOrientationMaskPortrait | UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight | UIInterfaceOrientationMaskPortraitUpsideDown), UIInterfaceOrientationMaskAllButUpsideDown = (UIInterfaceOrientationMaskPortrait | UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight), }
由上可以發現:
- iOS 6 及之后版本使用的
UIInterfaceOrientationMask
類型來控制屏幕屏幕方向,該類型也新增加了幾個枚舉取值,可用一個枚舉取值來代表多個屏幕方向,使用起來更方便。 - 注意在
UIInterfaceOrientation
中有注釋 Note that UIInterfaceOrientationLandscapeLeft is equal to UIDeviceOrientationLandscapeRight (and vice versa).
This is because rotating the device to the left requires rotating the content to the right,大意是界面的左轉相當于設備的右轉,如果設備向左轉時就需要內容(即界面)向右轉。即:
UIInterfaceOrientationLandscapeLeft = UIDeviceOrientationLandscapeRight
UIInterfaceOrientationLandscapeRight = UIDeviceOrientationLandscapeLeft
下面還會舉例說明。
其實UIDeviceOrientation
與UIInterfaceOrientation
是兩個互不相干的屬性,通常情況下會一起出現,在這里正好利用此特性在屏幕旋轉后進行重新布局。
-
第1步:監聽
UIDeviceOrientationDidChangeNotification
狀態//監聽設備旋轉 改變 視圖 對應位置 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(deviceOrientationDidChange) name:UIDeviceOrientationDidChangeNotification object:nil]; //用來控制橫豎屏時調整視圖位置 - (void)deviceOrientationDidChange { [self isPortrait]; }
-
第2步:重新布局
if (_interOrientation == UIInterfaceOrientationPortrait || _interOrientation == UIInterfaceOrientationPortraitUpsideDown) { self.top.constant = 145; self.bottom.constant = 210; } else if (_interOrientation == UIInterfaceOrientationLandscapeRight || _interOrientation == UIInterfaceOrientationLandscapeLeft) { self.top.constant = 40; self.bottom.constant = 50; }
例如:豎屏轉橫屏
界面豎屏UIInterfaceOrientationPortrait
->橫屏UIInterfaceOrientationLandscapeRight
,設備方向UIDeviceOrientationPortrait
->UIDeviceOrientationLandscapeLeft
,在設備發生變化這個過程觸發UIDeviceOrientationDidChangeNotification
監聽,然后進行重新布局。
3、旋轉時狀態欄的隱藏與顯示
-
這里只記述旋轉時狀態欄的變化,由豎屏想橫屏變化時狀態欄會消失。
//在需要的`UIViewController`設置是否隱藏 - (BOOL)prefersStatusBarHidden { NSLog(@"%s, line = %d",__FUNCTION__,__LINE__); return NO; }
4、鎖屏
鎖屏時,不管系統鎖屏是否關閉、Push 或 Present 返回后,界面依然保持不變。
-
第1步:設置鎖屏
- (IBAction)lockAction:(UIButton *)sender { if (_lockScreen) { _lockScreen = NO; [sender setTitle:@"鎖定屏幕" forState:UIControlStateNormal]; } else { _lockScreen = YES; [sender setTitle:@"解開屏幕" forState:UIControlStateNormal]; } _lockOrientation = _interOrientation; }
-
第2步:繞過強轉
- (void)interfaceOrientation:(UIInterfaceOrientation)orientation { [self isPortrait]; //鎖屏情況下 不旋轉 if (!_lockScreen) { [self setInterOrientation:orientation]; }
-
第3步:針對 Push 或 Present 返回后
- (void)viewWillAppear:(BOOL)animated { if (_lockScreen) { //記錄返回時的界面狀態 [self setInterOrientation:_lockOrientation]; } else { [self isPortrait]; } }
5、 針對特定UIViewController
方向的支持
-(UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {
if ([NSStringFromClass([[self topViewController] class]) isEqualToString:@"FirstViewController"]) {
//橫屏
return UIInterfaceOrientationMaskLandscapeRight;
}
//豎屏
return UIInterfaceOrientationMaskPortrait;
}
最后的獻上GitHub代碼,還有2個小的 bug ,有興趣的朋友歡迎來探討。
- 參考文章:
iOS 屏幕旋轉問題總結
iOS 屏幕方向那點事兒