ios 检测屏幕方向

方法一：通知中心监听

-(void)notifitionSatatus{    [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(statusBarOrientationChange:) name:UIApplicationDidChangeStatusBarOrientationNotification object:nil];
}
-(void)statusBarOrientationChange:(NSNotification*)notification{
    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
    if (orientation == UIInterfaceOrientationLandscapeRight) // home键靠右
    {

    }
    if (orientation ==UIInterfaceOrientationLandscapeLeft) // home键靠左
    {

    }
    if (orientation == UIInterfaceOrientationPortrait)//home在下
    {

    }
    if (orientation == UIInterfaceOrientationPortraitUpsideDown)
    {

    }
    NSLog(@"%ld",orientation);
}

注意：在没有打开屏幕旋转开关的情况下，该通知无效

方法二：陀螺仪监测

- (void)startMotionManager{
    if (_motionManager == nil) {
        _motionManager = [[CMMotionManager alloc] init];
    }　　//检测时间间隔
    _motionManager.deviceMotionUpdateInterval = 1.0;
    if (_motionManager.deviceMotionAvailable) {
        NSLog(@"Device Motion Available");
        [_motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue currentQueue]
                                            withHandler: ^(CMDeviceMotion *motion, NSError *error){
                                                [self performSelectorOnMainThread:@selector(handleDeviceMotion:) withObject:motion waitUntilDone:YES];

                                            }];
    } else {
        NSLog(@"No device motion on device.");
        [self setMotionManager:nil];
    }
}
- (void)handleDeviceMotion:(CMDeviceMotion *)deviceMotion{
    double x = deviceMotion.gravity.x;
    double y = deviceMotion.gravity.y;
    if (fabs(y) >= fabs(x))
    {
        if (y >=0){
             //UIDeviceOrientationPortraitUpsideDown;
            [self.delegate actionWithDeviceOrientation:UIDeviceOrientationPortraitUpsideDown];
        }
        else{
            // UIDeviceOrientationPortrait;
            [self.delegate actionWithDeviceOrientation:UIDeviceOrientationPortrait];
        }
    }
    else
    {
        if (x >= 0){
            // UIDeviceOrientationLandscapeRight;
            [self.delegate actionWithDeviceOrientation:UIDeviceOrientationLandscapeRight];
        }
        else{
            // UIDeviceOrientationLandscapeLeft;
            [self.delegate actionWithDeviceOrientation:UIDeviceOrientationLandscapeLeft];
        }
    }
}//停止检测
-(void)endMotionManager{
    [_motionManager stopDeviceMotionUpdates];
}