Why no animation in PageControl project? - iphone

Question

I'm using the PageControl project, which is on Apple's dev site. I've added a flip view to the project and an info icon to the top right of each view/page. For some reason, only the first page is able to animate the flipping. Page 2 on still shows the flipped page but does not animate. To make sure it isn't anything special about page 1, I switch page 1 and 2 and that worked fine. Page 2 in position 1 animated while Page 1 in position 2 did not. Any ideas why this would happen or how I can trouble shoot it?
I did take a look at this thread, which seems to be the same issue: Flip View Iphone. However, My flipview is a UIViewController and so is the class with the info icon on it. In the other thread, they are using UIViews.
I did implement the showInfo code from the above thread. When on Page 2, I see no flip. Then I scroll over to Page 1 and see it has flipped. Not sure why it isn't staying with Page 2. When on Page 1, it doesn't animate the flip. The flipview just suddenly appears.

Answer 1

Do you have a containerView? Something that can be there so you can add and remove subviews from it? Animation can break if you have two viewControllers, one coming and one going, without a containerView. I use a rootViewController and animate all my pages to and from each other with the rootViewcontroller in the back. Here is my code for flipping, you'll probably have to do a little editing to make it work for you:
(keep in mind that self is the rootViewcontroller, a viewcontroller with a blank view (color it so it matches your views))
- (void)switchTwoViews:(UIViewController *)view1 otherView:(UIViewController *)view2
{
/*
This method is called to switch views.
It flips the displayed view from the main view to the flipside view and vice-versa.
*/
UIViewController *coming = nil;
UIViewController *going = nil;
UIViewAnimationTransition transition;
[view1.view setUserInteractionEnabled: NO];
[view2.view setUserInteractionEnabled: NO];
if (view1.view.superview == nil) {
coming = view1;
going = view2;
transition = UIViewAnimationTransitionFlipFromLeft;
}
else {
coming = view2;
going = view1;
transition = UIViewAnimationTransitionFlipFromRight;
}
// in some cases the following is needed to size the view
// coming.view.frame = [UIScreen mainScreen].applicationFrame;
// going.view.alpha = 1.0; //uncomment these lines if we want fading of views
// coming.view.alpha = 0.0;
NSArray *viewArray = [[NSArray alloc] initWithObjects:coming, going, nil];
[coming viewWillAppear:YES];
[going viewWillDisappear:YES];
[UIView beginAnimations:#"View Flip" context:viewArray]; {
[UIView setAnimationDuration:1.0];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(animationDidEnd:finished:context:)];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
// coming.view.alpha = 1.0; //uncomment these lines if we want fading of views
// going.view.alpha = 0.0;
[UIView setAnimationTransition:transition forView:self.view cache:YES];
[self.view addSubview: coming.view];
}
[UIView commitAnimations];
}
- (void) animationDidEnd:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context
{
NSArray *viewArray = context;
[((UIViewController *)[viewArray objectAtIndex:1]).view removeFromSuperview];
[[viewArray objectAtIndex:1] viewDidDisappear:YES];
[[viewArray objectAtIndex:0] viewDidAppear:YES];
[[[viewArray objectAtIndex:0] view] setUserInteractionEnabled: YES];
[viewArray release];
}