gistfile1.m

[UIView transitionWithView:self.view
                  duration:0.25
                   options:UIViewAnimationOptionsTransitionCrossDissolve
                animations:^{
                    [self.view addSubview:overlay];
                }
                completion:nil];

gistfile2.m

[UIView transitionWithView:self.navigationController.view
                  duration:0.25
                   options:UIViewAnimationOptionsTransitionCrossDissolve
                animations:^{
                    [self.navigationController.view addSubview:overlay];
                }
		completion:nil];

gistfile3.m

[UIView transitionWithView:self.tabBarController.view
                  duration:0.25
                   options:UIViewAnimationOptionsTransitionCrossDissolve
                animations:^{
                    [self.tabBarController.view addSubview:overlay];
                }
		completion:nil];