Subview fade in and fade out help - iphone

Question

I am having a problem fading out my subview. I have no trouble fading the view in but fading out ..just drops the view.
-(void)flipToReview {
ReviewViewController *reviewVariable = [[ReviewViewController alloc] initWithNibName:#"ReviewViewController" bundle:nil];
[self setReviewViewController:reviewVariable];
self.ReviewViewController.view.alpha =0;
[UIView beginAnimations:#"flipview" context:nil];
[UIView setAnimationDuration:0.3];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:_window cache:YES];
[reviewVariable release];
[self.window addSubview:self.ReviewViewController.view];
self.ReviewViewController.view.alpha =1;
[UIView commitAnimations];
}
-(void)flipBackFromReview {
// self.ReviewViewController.view.alpha = 1;
[UIView beginAnimations:#"trip" context:nil];
[UIView setAnimationDuration:0.3];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:_window cache:NO];
self.ReviewViewController.view.alpha = 0;
[self.ReviewViewController.view removeFromSuperview];
[UIView commitAnimations];
self.window.rootViewController = self.tabBarController;
[self.window makeKeyAndVisible];
[self.ReviewViewController.view setHidden:1];
NSLog(#"remove subview");
}

Answer 1

Try the following:
[UIView animateWithDuration:3.0 delay:0.0
options:UIViewAnimationOptionAllowUserInteraction
animations:^{ ReviewViewController.view.alpha = 0.0;}
completion:^(BOOL fin) {
if (fin) [ReviewViewController.view removeFromSuperview];
}];

Answer 2

You need to move:
[self.ReviewViewController.view removeFromSuperview];
That cannot be done "over time" in an animation. What you want to do is move that to a selector and use setAnimationDelegate and setAnimationDidStopSelector. Put the following in your animation block:
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(finshedFadeOut)];
Then make the following method:
- (void)finshedFadeOut {
[self.ReviewViewController.view removeFromSuperview];
}

Answer 3

I had this issue as well, the way I got around it was changing the alpha to 0, instead of just removing the view. That can be animated.