iOS 横竖屏切换解决方案

iOS要实现横竖屏切换很简单，不需要使用任何第三方，只需要实现几个方法就可以了。demo下载地址：
https://github.com/qqcc1388/TYOrientationDemo
https://github.com/qqcc1388/iosLandscapeDemo

1.设置系统支持横竖屏【General】->【Targets】-> 【Deployment info】->【Device Orientation】

2.在控制器中实现对应的方法(默认支持竖屏)

-(BOOL)shouldAutorotate{
    return YES;
}

-(UIInterfaceOrientationMask)supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskPortrait;
}

3.某些特定的页面需要横屏支持的，则单独处理（同样需要实现2个方法）

-(BOOL)shouldAutorotate{
    return YES;
}

- (UIInterfaceOrientationMask)supportedInterfaceOrientations
{
    return (UIInterfaceOrientationMaskPortrait|UIInterfaceOrientationMaskLandscapeLeft|UIInterfaceOrientationMaskLandscapeRight);
}

4.如果控制器中有用到导航控制器或者tabbarController，这需要在导航控制器和tabbarController分别实现以下2个方法

- (BOOL)shouldAutorotate{
    
    return [self.selectedViewController shouldAutorotate];
}

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

5.如果需要实现点击按钮切换横竖屏的效果则可以参考如下方案：

//按钮点击事件
- (void)leftAction
{
    [self interfaceOrientation:UIInterfaceOrientationPortrait];
}

- (void)rightAction
{
    [self interfaceOrientation:UIInterfaceOrientationLandscapeRight];
}

- (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;
        // 从2开始是因为0 1 两个参数已经被selector和target占用
        [invocation setArgument:&val atIndex:2];
        [invocation invoke];
    }
}

6.如果要监听屏幕旋转事件则可以参考如下方案（监听旋转事件，控制键盘，控制frame等操作）

    UIDevice *device = [UIDevice currentDevice]; //Get the device object
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationChanged:) name:UIDeviceOrientationDidChangeNotification  object:device];

-(void)orientationChanged:(NSNotification *)noti{
    UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];
    switch (orientation) {
        case UIDeviceOrientationPortrait:            // Device oriented
            break;
        case UIDeviceOrientationPortraitUpsideDown:  // Device oriented
            break;
        case UIDeviceOrientationLandscapeLeft :      // Device oriented
            break;
        case UIDeviceOrientationLandscapeRight:      // Device oriented horizontally, home button on the left
            break;
        default:
            break;
    }
}

通过通知让app强制横屏或者强制竖屏
appdelegate添加属性

@property (nonatomic ,assign) BOOL allowRotation; 是否允许横屏

在appdelegate添加通知 并实现 方法

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(startFullScreen) name:@"startFullScreen" object:nil];//允许横屏
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(endFullScreen) name:@"endFullScreen" object:nil];//退出横屏

#pragma mark 允许横屏
-(void)startFullScreen
{
    AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
    appDelegate.allowRotation = YES;
    
    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 = UIInterfaceOrientationLandscapeRight;
        [invocation setArgument:&val atIndex:2];
        [invocation invoke];
    }
}
 
#pragma mark    退出横屏
-(void)endFullScreen
{
    AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
    appDelegate.allowRotation = NO;
 
//强制归正：
    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 =UIInterfaceOrientationPortrait;
        [invocation setArgument:&val atIndex:2];
        [invocation invoke];
    }
}

- (UIInterfaceOrientationMask )application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window{
    if (self.allowRotation) {
        return UIInterfaceOrientationMaskAll;
    }
    return UIInterfaceOrientationMaskPortrait;
}

在需要横屏的页面 通知发送启用横屏或者强制竖屏

-(void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
        
    [[NSNotificationCenter defaultCenter] postNotificationName:@"startFullScreen" object:nil];
}

-(void)viewWillDisappear:(BOOL)animated{
    [super viewWillDisappear:animated];
    
    [[NSNotificationCenter defaultCenter] postNotificationName:@"endFullScreen" object:nil];
}

-(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation{
    return UIInterfaceOrientationLandscapeLeft;
}