iOS竖屏应用，单个控制器横屏

这是前提：

QQ20170517-234959@2x.png

以下为步骤：
1.AppDelegate
新加属性 ：

@property (nonatomic, assign) BOOL allowRotate;

重写方法：

-(UIInterfaceOrientationMask)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {
    
    NSLog(@"方向  =============   %d", _allowRotate);
    if (_allowRotate) {
        return UIInterfaceOrientationMaskAll;
    }else{
        return (UIInterfaceOrientationMaskPortrait);
    }
}

2.公共的BaseTabBarController 、BaseNavigationController中无需添加任何代码

3.公共的BaseViewController重写，然后所有的控制器继承于BaseViewController.。之所以写个公共BaseViewController,好处就是：当需要改变控制器的一些属性时，一改全改

- (UIInterfaceOrientationMask)supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskPortrait;
}

4.需要横屏的控制器中：主要是在出现之前将 delegate.allowRotate 打开适配所有方向。
//此处需要在 需要 横屏的控制器 显示push或者present之前将AppDelegate中的属性改变，也可以在push或者present之前添加

AppDelegate * delegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
        delegate.allowRotate = YES;

为了解耦代码，我写在了init方法中

- (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{
    if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
        AppDelegate * delegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
        delegate.allowRotate = YES;
    }
    return self;
}
//在 push 走或者 dismiss走之前 还原设置，目的是为了push或者dismiss后能恢复竖屏，本来想写在ViewWillDisApeer中，发现有问题，故此改成了如下：
- (IBAction)s:(id)sender {
    AppDelegate * delegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
    delegate.allowRotate = NO;
    [self dismissViewControllerAnimated:YES completion:nil];
}
- (IBAction)pap:(id)sender {
    AppDelegate * delegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
    delegate.allowRotate = NO;
    [self presentViewController:[JCTest2ViewController new] animated:YES completion:nil];
}

- (BOOL)shouldAutorotate{
    return NO;
}

//想要的方向
- (UIInterfaceOrientationMask)supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskLandscapeRight;
}