Objective C UIKeyboardWillChangeFrameNotification

gistfile1.m

    [[NSNotificationCenter defaultCenter] addObserverForName:UIKeyboardWillChangeFrameNotification object:nil queue:nil usingBlock:^(NSNotification *note) {
        NSDictionary *dict = [note userInfo];
        NSValue *keyboardFrame = dict[UIKeyboardFrameEndUserInfoKey];
        CGRect frame = [keyboardFrame CGRectValue];
        NSNumber *duration = dict[UIKeyboardAnimationDurationUserInfoKey];
        double durationDouble = [duration doubleValue];
        [UIView animateWithDuration:durationDouble animations:^{
            self.view.frame = CGRectMake(0, frame.origin.y - self.view.frame.size.height, self.view.frame.size.width, self.view.frame.size.height);
        }];
    }];