ios 屏幕方向的设置

ref： http://www.cnblogs.com/niit-soft-518/p/5611298.html

实际的项目需求。root是TabBarController，里面有4个navigationController，现在要锁死所有页面的屏幕方向

try 1:继承navigation：然并卵

try 2: 继承tabbarcontroller：然并卵

try 3: 继承navigation，tabbar：然并卵

result：iOS9设置无效，iOS8以下，只需设置tabbar，只设置navigation没用

最后：iOS9以下的锁死实现：

#import "RootTabbarViewController.h"

@interface RootTabbarViewController ()

@end

@implementation RootTabbarViewController

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

//是否可以旋转
- (BOOL)shouldAutorotate
{
        NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];
        //读取保存的数据
        NSUInteger *isLock =[defaults integerForKey:@"ScreenLockSetting"];
        if(isLock==YES){
            return NO;
        }else return YES;
        //return isLock;

}

//优先竖屏
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
    return UIInterfaceOrientationPortrait;
}

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