ios - 使用复选标记配件显示在 swift 中选择的一个单元格

Question

我有一个设置屏幕，可以在两个单位系统(公制和英制)之间进行选择，并且希望在用户选择特定单元格时只显示一个复选标记，如果选择另一个单元格则切换复选标记。目前，我的代码选择了如图所示的两个单元格，并且当我稍后返回 View 时，不会将复选标记保存到所选单元格。

关于如何解决这个问题的任何想法。我在 stack 上看到过类似的问题，但大多数都在 ObjC 中。

代码:

override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {

        tableView.deselectRowAtIndexPath(indexPath, animated: true)

        var weightValue: String? = unitsDefaults.objectForKey(kCCWeightKeyMetric) as! String?
        var distanceValue: String? = unitsDefaults.objectForKey(kCCDistanceKeyMetric) as! String?
        let cell = tableView.cellForRowAtIndexPath(indexPath)


        if indexPath.row == 0 {

            weightValue = "pounds" //Set to this for the default value of weight
            unitsDefaults.setObject(weightValue, forKey: kCCWeightKeyMetric) //Save the kg value

            distanceValue = "miles" //Set to this for the default value of distance
            unitsDefaults.setObject(distanceValue, forKey: kCCDistanceKeyMetric) //Save the km value

            cell?.accessoryType = UITableViewCellAccessoryType.Checkmark

            unitsDefaults.synchronize()

            //Check mark Selection
            if unitsDefaults.stringForKey(kCCDistanceKeyMetric)! == "miles" {

                cell?.accessoryType = UITableViewCellAccessoryType.Checkmark

            } else if unitsDefaults.stringForKey(kCCDistanceKeyMetric)! == "km"{

                cell?.accessoryType = UITableViewCellAccessoryType.None
            }


        } else {

            weightValue = "kg" //Set to this for the default value of weight
            unitsDefaults.setObject(weightValue, forKey: kCCWeightKeyMetric) //Save the kg value

            distanceValue = "km" //Set to this for the default value of distance
            unitsDefaults.setObject(distanceValue, forKey: kCCDistanceKeyMetric) //Save the km value

            unitsDefaults.synchronize()

            //Check mark Selection
            if unitsDefaults.stringForKey(kCCDistanceKeyMetric)! == "km" {

                cell?.accessoryType = UITableViewCellAccessoryType.Checkmark

            } else if unitsDefaults.stringForKey(kCCDistanceKeyMetric)! == "miles"{

                cell?.accessoryType = UITableViewCellAccessoryType.None
            }


        }

        //Dismiss the View
        if let navController = self.navigationController {
            navController.popViewControllerAnimated(true)
        }

    }

Answer 1

做这个类型。我正在用 Objective-C 编写。您可以了解如何在 Swift 中执行。创建一个可变字典说'cellDictionary'

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cellIdentifier" forIndexPath:indexPath];
    NSString *cellRowString =[NSString stringWithFormat:@"%ld",(long)indexPath.row];
     if([cellDictionary valueForKey:cellRowString]!=nil){
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
    }
    else
    {
        cell.accessoryType = UITableViewCellAccessoryNone;
    }
    return cell;
}


-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString *cellRowString =[NSString stringWithFormat:@"%ld",(long)indexPath.row];
    if([cellDictionary valueForKey:cellRowString]==nil){
        [cellDictionary setObject:cellRowString forKey:cellRowString];
    }
     [tableView reloadData];
}