ios - 如何在 ios 中执行连续方向检测？

Question

我有一个简单的 if 语句来检测方向并执行操作。这很好用，但它只在第一次有效并且无法再次检测到。

这个 void 是否只被调用一次，如果是，我如何改变它以不断检查？

我需要将一些移动到 viewDidLoad 吗？

- (void) willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
    {
        [super willRotateToInterfaceOrientation:toInterfaceOrientation duration:duration];

        if (toInterfaceOrientation == UIInterfaceOrientationLandscapeRight)

        {
            [self.navigationController pushViewController:graphView animated:YES];

        }

            else if (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft)
            {
                [self.navigationController pushViewController:graphView animated:YES];
            }

            else if (toInterfaceOrientation == UIInterfaceOrientationPortrait)
            {
                [self.navigationController popToRootViewControllerAnimated:YES];
                NSLog(@"portrait");
            }

            else
            {
                [self.navigationController popToRootViewControllerAnimated:YES];

            }

        }

Answer 1

[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(orientationChanged:)
                                             name:@"UIDeviceOrientationDidChangeNotification" 
                                           object:nil];