Objective c, reposition a view above the keyboard in one single animation - objective-c

Question

I have a custom view at the bottom of my screen, i want to reposition it above the keyboard when it opens up.
I know i can register for the 'KeyboardWasShown' notification and then reposition the view or as the apple documentation suggests to use a scrollview with scrollRectToVisible, but the problem i have with both options is that it is not done as part of the keyboard animation.
I can see the keyboard appear and only a second later the view is repositioned or scrolled in to view.
Another option i tried was to set this view as InputAccessory for the textView im editing, This works very well but my view will not be visible once the keyboard is closed, and i need it to be available all the time.
I suppose i can create two instances of this view and have one as inputAccessory and the other just sitting in the bottom, but i really dont like this solution and these views have a state that will have to be synced between the two instances
Can anyone suggest an alternative solution ?

Answer 1

You better use UIKeyboardWillChangeFrameNotification notification.
Add observer first.
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardFrameChange:) name:UIKeyboardWillChangeFrameNotification object:nil];
The selector will be...
- (void)keyboardFrameChange:(NSNotification *)notification {
CGRect begin = [[notification.userInfo valueForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
CGRect end = [[notification.userInfo valueForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
CGFloat keyboardSize= begin.size.height;
BOOL isShowing = begin.origin.y > end.origin.y;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:[notification.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
[UIView setAnimationCurve:[notification.userInfo[UIKeyboardAnimationCurveUserInfoKey] integerValue]];
[UIView setAnimationBeginsFromCurrentState:YES];
// do view animation here.
[UIView commitAnimations];
}
The animation of your view and the keyboard will be sync.