MessagesViewController.m

- (void)keyboardWillHideOrShow:(NSNotification *)notification
{
    UIEdgeInsets tableInset = self.tableView.contentInset;
    CGPoint scrollOffset = self.tableView.contentOffset;
    UIToolbar *toolbar = self.navigationController.toolbar;
    CGRect toolbarFrame = toolbar.frame;

    NSDictionary *userInfo = notification.userInfo;
    NSTimeInterval duration = [[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    UIViewAnimationCurve curve = [[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
    CGFloat keyboardHeight = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size.height;

    if ([notification.name isEqualToString:@"UIKeyboardWillShowNotification"]) {
        toolbarFrame.origin.y -= keyboardHeight;
        tableInset.bottom += keyboardHeight;
        scrollOffset.y += keyboardHeight;
    } else {
        toolbarFrame.origin.y += keyboardHeight;
        tableInset.bottom -= keyboardHeight;
        scrollOffset.y -= keyboardHeight;
        if (scrollOffset.y < -tableInset.top) {
            scrollOffset.y = -tableInset.top;
        }
    }
    // Run animation
    [UIView beginAnimations:nil context: nil];
    [UIView setAnimationCurve:curve];
    [UIView setAnimationDuration:duration];
    toolbar.frame = toolbarFrame;
    self.tableView.contentInset = tableInset;
    self.tableView.contentOffset = scrollOffset;
    [UIView commitAnimations];
}