Adding a UITextField to a UITableViewCell

Hey I've been looking for this problem and also found some topics to my question but I'm obviously not getting what I'm doing wrong, so here's my problem I have a UITableViewCell and want to add a UITextFiel to it. So I setup a TextFiel and add it to the Cell in the cellForRowAtIndexPathRow:, but when I select the row or to be precisely the TextField no keyboard or shows up and I also can't see a placeholder.

Here's my code:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell" forIndexPath:indexPath];
    UITextField *textField = [[UITextField alloc] initWithFrame:CGRectZero];

    textField.delegate = self;
    textField.placeholder = NSLocalizedString(@"Description", nil);
    [cell addSubview:textField];

    return cell;
}

- (BOOL)tableView:(UITableView *)tableView shouldHighlightRowAtIndexPath:(NSIndexPath *)indexPath
{
    return nil;
}

I would appreciate your help ;)