UIView removeFromSuperview inside animation PROPERLY - ios

Question

Now, this question have partially been asking alot, but none actually considering how (or when) the messages -viewWillDisappear & -viewDidDisappear are being sent. Almost every example use the following design:
[UIView animateWithDuration:0.5
delay:1.0
options: UIViewAnimationCurveEaseOut
animations:^{
yourView.alpha = 0;
}completion:^(BOOL finished){
[yourView removeFromSuperview]; // Called on complete
}];
The problem with this is that these messages will both be sent when de animation ends!
Now, -addSubview can be animated (if put inside the animations-block) which will send the corresponding messages (-viewWillAppear & -viewDidAppear) with correct timedifference. So naturally one would place -removeFromSuperview inside the animations-block. This WILL send the messages correctly, but the view is actually removed instantly making the animation... Well, it won't animate because nothing is left to animate!
Is this intentional from apple and if so, why? How do you do it correctly?
Thanks!
Edit.
Just to clearify what I'm doing:
I got a custom segue, vertically animating a Child-ViewController down from top which works as expected with the following code:
-(void)perform{
UIViewController *srcVC = (UIViewController *) self.sourceViewController;
UIViewController *destVC = (UIViewController *) self.destinationViewController;
destVC.view.transform = CGAffineTransformMakeTranslation(0.0f, -destVC.view.frame.size.height);
[srcVC addChildViewController:destVC];
[UIView animateWithDuration:0.5f
animations:^{
destVC.view.transform = CGAffineTransformMakeTranslation(0.0f, 0.0f);
[srcVC.view addSubview:destVC.view];
}
completion:^(BOOL finished){
[destVC didMoveToParentViewController:srcVC];
}];
}
Here it will happen in the following order (thanks to -addSubview being inside the animations-block):
Add childView (will automatically invoke -willMoveToParentViewController)
-addSubview will invoke -viewWillAppear
When the animation finishes, -addSubview will invoke -viewDidAppear
Manually invoke -didMoveToParentViewController inside the completion-block
Above is the exact expected behavior (just like the built-in transitions behave).
With the following code to do the above segue but backwards (with an unwindSegue):
-(void)perform{
UIViewController *srcVC = (UIViewController *) self.sourceViewController;
srcVC.view.transform = CGAffineTransformMakeTranslation(0.0f, 0.0f);
[srcVC willMoveToParentViewController:nil];
[UIView animateWithDuration:5.5f
animations:^{
srcVC.view.transform = CGAffineTransformMakeTranslation(0.0f, -srcVC.view.frame.size.height);
}
completion:^(BOOL finished){
[srcVC.view removeFromSuperview]; // This can be done inside the animations-block, but will actually remove the view at the same time ´-viewWillDisappear´ is invoked, making no sense!
[srcVC removeFromParentViewController];
}];
}
the flow will be like this:
Manually invoke -willMoveToParentView:nil to notify that it will be removed
When the animation finishes, both -viewWillDisappear & -viewDidDisappear will be invoked simultaneously (wrong!) and -removeFromParentViewController will automatically invoke -didMoveToParentViewController:nil.
And if I now move -removeFromSuperview in to the animations-block, the events will be sent correctly but the view is removed when the animation starts instead of when the animation finishes (this is the part that makes no sense, following how -addSubview behaves).

Answer 1

Your question is about removing view controller, because, viewWillDisappear and viewDidDisappear are method of view controller.
viewWillDisappear: will be called from completion block, not earlier, because this is the place where you said that you want to remove subview from main view.
If you want to remove some property before that point, then in child controller override willMoveToParentViewController: method. This method will be called before animation block.
Here's code example:
//Prepare view for removeing.
[self.childViewController willMoveToParentViewController:nil];
[UIView animateWithDuration:0.5
delay:1.0
options: UIViewAnimationOptionCurveEaseOut
animations:^{
self.childViewController.view.alpha = 0;
}completion:^(BOOL finished){
[self.childViewController.view removeFromSuperview];
[self.childViewController didMoveToParentViewController:self];
}];
So, the flow will be:
First willMoveToParentViewController: with nil parameter will be called
Animation block will start and view will set it's alpha property to 0
When animation finish, completion block will start to execute...
[self.childViewController.view removeFromSuperview]; will be called first
Then viewWillDissapear: in childViewController will be called
Then [self.childViewController didMoveToParentViewController:self];
And at the end viewDidDissapear: in childViewController will execute.
Pre request for this flow is that you embed childViewController with code like this:
[self addChildViewController:self.childViewController];
[self.view addSubview:self.childViewController.view];
[self.childViewController didMoveToParentViewController:self];