无论屏幕方向如何,iPhone中心活动指示器

Question

无论屏幕方向如何,我如何以编程方式居中设置活动指示器？

Answer 1

尝试设置center活动视图的属性,如下所示:

 activity.center = CGPointMake(self.view.frame.size.width/2,self.view.frame.size.height/2);

在viewDidLoad,注册设备轮换的通知:

- (void)viewDidLoad {
   [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
   [[NSNotificationCenter defaultCenter] addObserver:self
        selector:@selector(didRotate:)
        name:UIDeviceOrientationDidChangeNotification object:nil];
}

并实施 didRotate:

-(void)didRotate:(NSNotification *)notification {   
   if (activity) {
    activity.center = CGPointMake(self.view.frame.size.width/2,self.view.frame.size.height/2);
    }
}