如何在设备方向事件(不是界面方向)上订阅自己?

时间:2011-01-21 11:40:45

标签: iphone cocos2d-iphone box2d

在我的应用程序中我想在设备旋转(方向更改)的情况下调用CCScene myscene中的一些方法。我禁用了自动旋转(因为我希望它不会发生)。

问题是:我想根据设备方向改变场景中的重力。 我的代码:

-(void) onEnter
{
    [super onEnter];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notification_OrientationWillChange:) name:UIApplicationWillChangeStatusBarOrientationNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(notification_OrientationDidChange:) name:UIApplicationDidChangeStatusBarOrientationNotification object:nil];
}
-(void) onExit
{
    //[[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationWillChangeStatusBarOrientationNotification object:nil];
    //[[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidChangeStatusBarOrientationNotification object:nil];
}
-(void)notification_OrientationWillChange:(NSNotification*)n
{
    orientation = (UIInterfaceOrientation)[[n.userInfo objectForKey:UIApplicationStatusBarOrientationUserInfoKey] intValue];
}
-(void)notification_OrientationDidChange:(NSNotification*)n
{
    if (orientation == UIInterfaceOrientationLandscapeLeft) {
        b2Vec2 gravity( 0, -10);
        world->SetGravity(gravity);
    }
    if (orientation == UIInterfaceOrientationLandscapeRight) {
        b2Vec2 gravity( 0, 10);
        world->SetGravity(gravity);
    }
}

但在这种情况下,我只能在启用自动旋转的情况下收到通知。(如果禁用,设备实际上不会更改状态栏方向) 你能救我吗?

1 个答案:

答案 0 :(得分:29)

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



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

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

您必须检查设备方向而非状态栏。

typedef enum {
        UIDeviceOrientationUnknown,
        UIDeviceOrientationPortrait,            // Device oriented vertically, home button on the bottom
        UIDeviceOrientationPortraitUpsideDown,  // Device oriented vertically, home button on the top
        UIDeviceOrientationLandscapeLeft,       // Device oriented horizontally, home button on the right
        UIDeviceOrientationLandscapeRight,      // Device oriented horizontally, home button on the left
        UIDeviceOrientationFaceUp,              // Device oriented flat, face up
        UIDeviceOrientationFaceDown             // Device oriented flat, face down
    } UIDeviceOrientation;