我可以观察UIViewController更改interfaceOrientation的时间吗？

Question

如果我有一个指向UIViewController的指针，当它改变interfaceOrientation而不修改控制器的代码时，我可以得到通知吗？

是我最好的选择，检测设备方向的变化，然后看看UIViewController是否会旋转（d）？

Answer 1

您可以使用NSNotificationCenter：

[[NSNotificationCenter defaultCenter] addObserver:self // put here the view controller which has to be notified 
             selector:@selector(orientationChanged:) 
              name:@"UIDeviceOrientationDidChangeNotification" 
              object:nil]; 
- (void)orientationChanged:(NSNotification *)notification{ 
    UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation]; 

    //do stuff 
    NSLog(@"Orientation changed");   
} 

Answer 2

您可以使用您的UIViewController的willAnimateRotationToInterfaceOrientation:duration:方法，然后重新任何UIViews（或任何其他代码）横向或纵向。例如。

- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration { 
    if (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft || toInterfaceOrientation == UIInterfaceOrientationLandscapeRight) { 
    // change positions etc of any UIViews for Landscape 
    } else { 
    // change position etc for Portait 
    } 

    // forward the rotation to any child view controllers if required 
    [self.rootViewController willAnimateRotationToInterfaceOrientation:toInterfaceOrientation duration:duration]; 
}