Switch View with Programming .....

- (IBAction)switchViews:(id)sender{

    if (self.yellowViewController == nil)
    {
        YellowViewController *yellowController = [[YellowViewController alloc]
                initWithNibName:@"YellowView" bundle:nil];
        self.yellowViewController = yellowController;
        [yellowController release];
    }

    [UIView beginAnimations:@"View Flip" context:nil];
    [UIView setAnimationDuration:1.25];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];

    UIViewController *coming = nil;
    UIViewController *going = nil;
    UIViewAnimationTransition transition;

    if (self.blueViewController.view.superview == nil) 
    {   
        coming = blueViewController;
        going = yellowViewController;
        transition = UIViewAnimationTransitionFlipFromLeft;
    }
    else
    {
        coming = yellowViewController;
        going = blueViewController;
        transition = UIViewAnimationTransitionFlipFromRight;
    }

    [UIView setAnimationTransition: transition forView:self.view cache:YES];
    [coming viewWillAppear:YES];
    [going viewWillDisappear:YES];
    [going.view removeFromSuperview];
    [self.view insertSubview: coming.view atIndex:0];
    [going viewDidDisappear:YES];
    [coming viewDidAppear:YES];

    [UIView commitAnimations];
}