iOS - Adding Target/Action for UITextField Inside Custom UITableViewCell

Question

I have UITableView which uses a custom UITableViewCell containing a UITextField.

I want to call a method (myMethod) when it is clicked (UIControlEventTouchDown) and attempted to wire this up inside the UITableView delegate method cellForRowAtIndexPath by doing the following:

[tf addTarget:self action:@selector(myMethod) forControlEvents:UIControlEventTouchDown];

When the UITextField is clicked, nothing happens.

I attempted to do the exact same thing for another UITextField outside of the UITableView:

[othertf addTarget:self action:@selector(myMethod) forControlEvents:UIControlEventTouchDown];

When I click on othertf the method is called as I would expect.

I'm a bit confused as the code is identical apart from I've swapped tf for othertf.

以下是完整的代码cellForRowAtIndexPath:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *DetailCellIdentifier = @"DetailFieldView";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:DetailCellIdentifier];
    if (cell == nil) {
        NSArray *cellObjects = [[NSBundle mainBundle] loadNibNamed:DetailCellIdentifier owner:self options:nil];
        cell = (UITableViewCell*) [cellObjects objectAtIndex:0];
    }
    cell.selectionStyle = UITableViewCellSelectionStyleNone;

    UITextField *tf = (UITextField *)[cell viewWithTag:2];
    tf.text = @"some value";

    [othertf addTarget:self action:@selector(myMethod) forControlEvents:UIControlEventTouchDown];
    [tf addTarget:self action:@selector(myMethod) forControlEvents:UIControlEventTouchDown];

    return cell;
}

谁能发现我做错了什么？这可能是一件简单的事情,因为我是iOS开发的新手.

Answer 1

使用UITextField delegate方法:

UITextField委托

//Use this method insted of addTarget:
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {

    if (textField == tf) {
        [self myMethod];
        return NO;
    }

  return YES;
}

并且不要忘记将委托设置为textField:

 tf.delegate = self;