iOS5中如何获取默认的LandscapeLeft方向？

抱歉，如果这个问题重复，但我找不到相同的解决方案。 在 iOS6 中，如果我想为一个 UIViewController 设置默认方向，我只需使用：

- (BOOL)shouldAutorotate {
    return YES;
}
- (NSUInteger)supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskLandscapeLeft;
}

但是如何在iOS5中做同样的事情，我测试了两者：

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation {
    return (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft);//not default
}
and
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation {
    return (toInterfaceOrientation == UIInterfaceOrientationMaskLandscapeLeft);// = return NO;
}

但默认方向始终是纵向。有什么建议吗？

调用下面的方法来检查orientation.happy编码的状态:-)

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
    [self CheckForViewForOrientation:toInterfaceOrientation];
}

- (void) CheckForViewForOrientation:(UIInterfaceOrientation)orientation
{
    if (orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown)
    {
        //Ur lable portrait view
    }
    else if (orientation == UIInterfaceOrientationLandscapeLeft || orientation == UIInterfaceOrientationLandscapeRight)
    {
        //Ur lable for landscape view
    }
}