iphone - 使用标签检索 UITextField

Question

我有以下代码:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (indexPath.row == 0)
        cell.tag = 0;
    else {
        cell.tag = 1;
    }

    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];

        UILabel *startDtLbl = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 80, 25)];
        if (indexPath.row == 0)
            startDtLbl.text = @"Username";
        else {
            startDtLbl.text = @"Password";
        }

        startDtLbl.backgroundColor = [UIColor clearColor];

        [cell.contentView addSubview:startDtLbl];

        UITextField *passwordTF = [[UITextField alloc] initWithFrame:CGRectMake(100, 5, 200, 35)];
        passwordTF.delegate = self;
        if (indexPath.row == 0)
            passwordTF.tag = 2;
        else {
            passwordTF.tag = 3;
        }
        [cell.contentView addSubview:passwordTF];
    }
    return cell;
}

我想获取 UITextField，我该怎么做？我尝试了以下但失败了:

UITableViewCell * username_cell = (UITableViewCell*)[self.view viewWithTag:0];
    UITableViewCell * password_cell = (UITableViewCell*)[self.view viewWithTag:1];

    UITextField * username = (UITextField*)[username_cell.contentView viewWithTag:2];
    UITextField * password = (UITextField*)[password_cell.contentView viewWithTag:3];
    NSLog(@"Username is %@", [username text]);
    NSLog(@"Password is %@", [password text]);

Answer 1

您应该停止使用标签来获取单元格。您应该为此使用 indexPaths。

替换

UITableViewCell * username_cell = (UITableViewCell*)[self.view viewWithTag:0];
UITableViewCell * password_cell = (UITableViewCell*)[self.view viewWithTag:1];

与

NSIndexPath *indexPathUserName = [NSIndexPath indexPathForRow:0 inSection:0];
UITableViewCell * username_cell = [self.tableView cellForRowAtIndexPath:indexPathUserName];
NSIndexPath *indexPathPassword = [NSIndexPath indexPathForRow:1 inSection:0];
UITableViewCell * password_cell = [self.tableView cellForRowAtIndexPath:indexPathPassword];

---

当你想引用一个特定的 View 时，你不能使用标签 0。因为所有没有自定义标签的标签都有一个标签 0。所以如果你使用 viewWithTag:0，你会得到最后添加的 View 。通常这不是您想要的 View 。