iphone - 查看旋转通知 : why didRotateFromInterfaceOrientation: doesn't get called?

Question

我正在尝试检测任何设备方向变化，以便我可以更新 View 。

无论方向是纵向还是横向，我都想更新 View ，所以我实现了这个方法:

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Return YES for supported orientations.
return (interfaceOrientation == UIInterfaceOrientationPortrait || interfaceOrientation == UIInterfaceOrientationLandscapeRight || interfaceOrientation == UIInterfaceOrientationLandscapeLeft);
}

我知道如果我想更新 View 以正确显示当前方向，我将需要实现以下一些方法:

– willRotateToInterfaceOrientation:duration:
– willAnimateRotationToInterfaceOrientation:duration:
– didRotateFromInterfaceOrientation:
– willAnimateFirstHalfOfRotationToInterfaceOrientation:duration:
– didAnimateFirstHalfOfRotationToInterfaceOrientation:
– willAnimateSecondHalfOfRotationFromInterfaceOrientation:duration:

现在，问题是我不明白为什么当我旋转模拟器时这些方法都没有被触发。

我也试过这段代码:

[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];

但还是没有。所以我想知道，模拟器会触发旋转通知吗？ 如果是，我做错了什么？

Answer 1

你需要添加类似

的通知观察者

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

并添加方法

- (void) didRotate:(NSNotification *)notification
{   
      UIDeviceOrientation orientation = [[UIDevice currentDevice] orientation];

       if (orientation == UIDeviceOrientationLandscapeLeft)
      {
        NSLog(@"Landscape Left!");
      }
}