키보드가 테이블뷰 하단에 있는 텍스트필드를 가리지 않도록 하는 방법

- (void)keyboardWillShow:(NSNotification *)notification {
    NSDictionary *info = [notification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    self.tableView.contentInset = UIEdgeInsetsMake(0, 0, kbSize.height, 0);
}

- (void)keyboardWillHide:(NSNotification *)notification {
    self.tableView.contentInset = UIEdgeInsetsZero;
}