iOS 获取屏幕方向，和强制屏幕旋转

iOS 获取屏幕方向

建议使用[UIApplication sharedApplication].statusBarOrientation来判断

    UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
    if (orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown) {
        
    }else {
        
    }

使用UIDevice来获取屏幕方向（不推荐，第一次获取的时候会获得UIDeviceOrientationUnknown）

UIDeviceOrientation duration = [[UIDevice currentDevice] orientation];

UIDeviceOrientation 枚举定义如下：

typedef NS_ENUM(NSInteger, UIDeviceOrientation) {
    UIDeviceOrientationUnknown,
    UIDeviceOrientationPortrait,            // Home按钮在下
    UIDeviceOrientationPortraitUpsideDown,  // Home按钮在上
    UIDeviceOrientationLandscapeLeft,       // Home按钮右
    UIDeviceOrientationLandscapeRight,      // Home按钮左
    UIDeviceOrientationFaceUp,              // 手机平躺，屏幕朝上
    UIDeviceOrientationFaceDown             //手机平躺，屏幕朝下
} __TVOS_PROHIBITED;

强制屏幕旋转

- (void)interfaceOrientation:(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;
        [invocation setArgument:&val atIndex:2];
        [invocation invoke];
    }
}

注意

一、需要勾选Device Orientation中的Portrait(竖屏)和其他的Landscape Left(向左横屏)或者Landscape Right(向右横屏)

勾选需要的屏幕方向

二、ViewController 里需要实现如下方法：

//是否自动旋转,返回YES可以自动旋转  
- (BOOL)shouldAutorotate NS_AVAILABLE_IOS(6_0) __TVOS_PROHIBITED;  
//返回支持的方向  
- (UIInterfaceOrientationMask)supportedInterfaceOrientations NS_AVAILABLE_IOS(6_0) __TVOS_PROHIBITED;  
//这个是返回优先方向  
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation NS_AVAILABLE_IOS(6_0) __TVOS_PROHIBITED;

三、若window的rootViewController 是 UINavigationController，为UINavigationController添加一个分类UINavigationController+Revolve，代码如下：

//是否自动旋转,返回YES可以自动旋转  
- (BOOL)shouldAutorotate { 
    return [self.topViewController shouldAutorotate];
}
//返回支持的方向  
- (NSUInteger)supportedInterfaceOrientations {
    return [self.topViewController supportedInterfaceOrientations];
}
//这个是返回优先方向  
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
    return [self.topViewController preferredInterfaceOrientationForPresentation];
}

四、 若window的rootViewController 是 UITabbarController，为UITabbarController添加一个分类UITabbarController+Revolve，代码如下：

//是否自动旋转,返回YES可以自动旋转  
- (BOOL)shouldAutorotate { 
    return [self.selectedViewController shouldAutorotate];
}
//返回支持的方向  
- (NSUInteger)supportedInterfaceOrientations {
    return [self.selectedViewController supportedInterfaceOrientations];
}
//这个是返回优先方向  
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
    return [self.selectedViewController preferredInterfaceOrientationForPresentation];
}