Keyboard Show/Hidde Event

keyboard.m

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification object:nil];
    
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
    
}

- (void)keyboardWillShow:(NSNotification *)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGRect keyboardRect = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    keyboardRect = [self.view convertRect:keyboardRect fromView:nil];
    CGSize kbSize = keyboardRect.size;
//    OPLog(@"keyboardRect: %@", NSStringFromCGRect(keyboardRect));
    
    double duration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    NSInteger curve = [[info objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
    CGFloat width = self.view.bounds.size.width;
    CGFloat heigth = self.view.bounds.size.height;
    
//    OPLog(@"%.3f %d size: %@", duration, curve, NSStringFromCGSize(kbSize));
    
    [UIView beginAnimations:@"OPKeyBoardShow" context:NULL];
    [UIView setAnimationDuration:duration];
    [UIView setAnimationCurve:curve];
    _commentContainerView.frame = CGRectMake(0, heigth - kbSize.height - _commentContainerView.frame.size.height, width, _commentContainerView.frame.size.height);
    [UIView commitAnimations];
}

- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    CGFloat width = self.view.bounds.size.width;
    CGFloat height = self.view.bounds.size.height;
    
    NSDictionary* info = [aNotification userInfo];
    double duration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    NSInteger curve = [[info objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
    
//    OPLog(@"%.3f %d", duration, curve);
    
    [UIView beginAnimations:@"OPKeyBoardHidde" context:NULL];
    [UIView setAnimationDuration:duration];
    [UIView setAnimationCurve:curve];
    _commentContainerView.frame = CGRectMake(0, height - _commentContainerView.frame.size.height, width, _commentContainerView.frame.size.height);
    [UIView commitAnimations];
}