说明：目前在ios7，ios8上验证有效，注意该UIViewController不能添加到UINavigationController，只能presentViewController方式添加。
- (BOOL)shouldAutorotate
{
return NO;
}
- (NSUInteger)supportedInterfaceOrientations
{
// 强制横屏
return UIInterfaceOrientationMaskLandscapeRight;
}
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
// 强制横屏
return UIInterfaceOrientationLandscapeRight;
}