Question

你今天过得怎样，希望一切顺利

我的问题是我在uitableviewcell中有uiswitch。但是，当我使用contentview将开关添加为单元格中的子视图时，它不会出现在我的单元格中？请问您知道为什么他们没有出现在每个自定义单元格上吗？提前致谢。

这是我的代码：

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

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];

    UISwitch *switchController = nil ;

    if (cell == nil)
    {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
                                      reuseIdentifier:@"Cell"];

      switchController=  [[UISwitch alloc] initWithFrame:CGRectZero];
        switchController.tag=100;
        [cell.contentView addSubview:switchController];
        CGRect switchFrame = switchController.frame;
        switchFrame.origin.x = 50.0f;
        switchFrame.origin.y = 10.0f;
        switchController.frame = switchFrame;
        [switchController addTarget:self action:@selector(switchChanged:) forControlEvents:UIControlEventValueChanged];

    }

    else
    {
        switchController =(UISwitch *)[cell.contentView viewWithTag:100];

    }

//This for persist switch state when scroll up or down 
    if ([[[self.SwitchArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row ]isEqualToString:@"ON"])
    {

        switchController.on=YES;

    }
    else
    {
        switchController.on=NO;
    }

   NSString *value = [[mainArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row];
    cell.textLabel.text = value;
    cell.textLabel.textAlignment = NSTextAlignmentRight;
    cell.textLabel.font = [UIFont systemFontOfSize:15.0];

    return cell;

}

以下是SwitchChanged的代码：

-(void)switchChanged:(UISwitch *)sender
{
    UITableViewCell *cell = (UITableViewCell *)[[sender superview] superview];
    NSIndexPath *index=[mainTableView indexPathForCell:cell];

    if (sender.on)
    {

        [[self.SwitchArray objectAtIndex:index.section] replaceObjectAtIndex:index.row withObject:@"ON"];

    }
    else
    {
        //Update my switch states array 
        [[self.SwitchArray objectAtIndex:index.section] replaceObjectAtIndex:index.row withObject:@"OFF"];

   }

    [padFactoids setObject:[NSKeyedArchiver archivedDataWithRootObject:SwitchArray] forKey:@"savedArray"];
    [padFactoids synchronize];

}

Answer 1

首先，你有一个宽度和高度为0的框架。其次，如果您正在使用带有原型单元格的故事板，那么它可能根本不会进入if (cell == nil)。希望这会有所帮助。

修改

将故事板中的开关添加到原型单元格会更容易，但如果您想以编程方式进行，则可以将代码移到if之外并添加如下条件：

UISwitch *switchController = (UISwitch *)[cell viewWithTag:100]; if (!switchController) { switchController= [[UISwitch alloc] initWithFrame:CGRectZero]; switchController.tag=100; [cell.contentView addSubview:switchController]; CGRect switchFrame = switchController.frame; switchFrame.origin.x = 50.0f; switchFrame.origin.y = 10.0f; switchController.frame = switchFrame; [switchController addTarget:self action:@selector(switchChanged:) forControlEvents:UIControlEventValueChanged]; }

当然，不要忘记设置宽度和高度。

Answer 2

您的switchController宽度和高度为0.首先使用CGRectZero初始化开关，然后更改原点坐标，但宽度和高度仍为0.

Answer 3

我找到了你的问题，尝试这样的工作。这里的问题是，在添加开关后，您将为单元格标签提供标题，这意味着标签会隐藏您的开关。

Problem：cell.textLabel隐藏了开关。

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

        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];

        UISwitch *switchController = nil ;

        if (cell == nil)
        {
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
                                          reuseIdentifier:@"Cell"];

        NSString *value = [[mainArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row];
        cell.textLabel.text = value;
        cell.textLabel.textAlignment = NSTextAlignmentRight;
        cell.textLabel.font = [UIFont systemFontOfSize:15.0];
          switchController=  [[UISwitch alloc] initWithFrame:CGRectZero];
            switchController.tag=100;
            [cell.contentView addSubview:switchController];
            CGRect switchFrame = switchController.frame;
            switchFrame.origin.x = 50.0f;
            switchFrame.origin.y = 10.0f;
            switchController.frame = switchFrame;
            [switchController addTarget:self action:@selector(switchChanged:) forControlEvents:UIControlEventValueChanged];

        }

        else
        {
            switchController =(UISwitch *)[cell.contentView viewWithTag:100];

        }

    //This for persist switch state when scroll up or down 
        if ([[[self.SwitchArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row ]isEqualToString:@"ON"])
        {

            switchController.on=YES;

        }
        else
        {
            switchController.on=NO;
        }



        return cell;

    }

Answer 4

根据您的评论，我发现您正在使用故事板创建表格视图。将开关添加到表视图原型单元格并将标记指定为100.

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

 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];
 UISwitch *switchController =(UISwitch *)[cell viewWithTag:100];

 [switchController addTarget:self action:@selector(switchChanged:) forControlEvents:UIControlEventValueChanged];

//This for persist switch state when scroll up or down 
if ([[[self.SwitchArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row ]isEqualToString:@"ON"])
{

    switchController.on=YES;

}
else
{
    switchController.on=NO;
}

 NSString *value = [[mainArray objectAtIndex:indexPath.section] objectAtIndex:indexPath.row];
cell.textLabel.text = value;
cell.textLabel.textAlignment = NSTextAlignmentRight;
cell.textLabel.font = [UIFont systemFontOfSize:15.0];

return cell;


}

内容添加子视图不起作用？

4 个答案: