Landscape background frame incorrect

[swl367]

In the following code, it looks like an app in landscape mode doesn't correctly fill the screen (see attached).

+ (void)showBackground
{
    if (!__si_alert_background_window) {
        __si_alert_background_window = [[SIAlertBackgroundWindow alloc] initWithFrame:[UIScreen mainScreen].bounds
                                                                         andStyle:[SIAlertView currentAlertView].backgroundStyle];
        [__si_alert_background_window makeKeyAndVisible];
        __si_alert_background_window.alpha = 0;
        [UIView animateWithDuration:0.3
                     animations:^{
                             __si_alert_background_window.alpha = 1;
                     }];
   }
}

[swl367]

looks like

        __si_alert_background_window.rootViewController = [UIViewController new];

solves the problem.