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How can I keep track if the Cell was assigned a tag number? I'll have anywhere from 10 - 90 cells created. However, when I scroll up and down (in and out-of-view), after cells are recreated, the cell Tag number continue to increase. 

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{  
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    NSManagedObject *managedObject = rowModels[indexPath.row];
    NSString  *entityName= [[managedObject entity]name];
    cell.textLabel.text = [NSString stringWithFormat:@"%@   %i", entityName, [indexPath row]];


    cell.tag = cellTagIndex++;
    NSString *tagString = [NSString stringWithFormat:@"%d", cell.tag];

    //cellToObjectMap is NSMutableDictionary

    if ([entityName isEqualToString:@"Test1" ])
    {
        [cellToObjectMap setValue:[managedObject valueForKey:@"test1_id"] forKey:tagString];
    }
    else if ([entityName isEqualToString:@"Test2t" ])
    {
        [cellToObjectMap setValue:[managedObject valueForKey:@"test2_id"] forKey:tagString];
    }

    NSLog(@"Cell.tag %@    Value:  %@", tagString, [cellToObjectMap objectForKey:tagString]);

    return cell;

}

Log:

2013-08-15 19:07:57.243 Time[8510:c07] Cell.tag 0    Value:  95AB73F8-E0C2-4D17-B6BE-9FC2E696959D
2013-08-15 19:07:57.244 Time[8510:c07] Cell.tag 1    Value:  EA163C15-0CF1-4275-B939-0ED9F62C240D
2013-08-15 19:07:57.245 Time[8510:c07] Cell.tag 2    Value:  DDFD36F6-4CAD-4C26-A38C-B22D827199BD
2013-08-15 19:07:57.245 Time[8510:c07] Cell.tag 3    Value:  AC9FD255-08CF-44C4-B168-E6441D08AC54
2013-08-15 19:07:57.246 Time[8510:c07] Cell.tag 4    Value:  48C2DE0C-88C3-48CC-BBB1-350088EE9862
2013-08-15 19:07:57.247 Time[8510:c07] Cell.tag 5    Value:  5C4495A1-FF3D-439E-BD01-88312EF881AD

........  
........ // Cell.tag continues to increase as I scroll up and down the screen.   

2013-08-15 19:10:38.903 Time[8510:c07] Cell.tag 254    Value:  81CAA228-51F4-464C-8B2B-12D2A66C3BA8
2013-08-15 19:10:38.969 Time[8510:c07] Cell.tag 255    Value:  7DC03657-B987-4994-8066-5393F77D891B
2013-08-15 19:10:39.052 Time[8510:c07] Cell.tag 256    Value:  BB1BCFD2-FBD9-46FA-B662-56085254FD46
2013-08-15 19:10:39.169 Time[8510:c07] Cell.tag 257    Value:  0C78EBE0-AD83-4A21-8546-37EA17EAB5CA

How can I keep track if a cell number was already assigned a cell.tag, and if it has, how can I be sure if the dictionary has the existing key?

4

2 回答 2

2

您只需要为每个新单元格分配一个标签，对吗？

像这样定义一个静态标签

#define CELL_TAG 100000

现在在你的 cellForRowAtIndexPath

cell.tag = indexPath.row + CELL_TAG

您添加的后缀表达式将始终增加标签，因此也将其删除。

PS。单元初始化在哪里？如果你需要那个

static NSString *CellIdentifier = @"Cell";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell==nil)
{
    cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
于 2013-08-16T02:40:28.287 回答
1

如果您需要将模型中的对象与单元格关联，请不要直接在单元格之间建立关联，因为单元格会不断重复使用。相反，将其与索引路径相关联。

假设cellToObjectMap是NSMutableDictionary，然后尝试：

[cellToObjectMap setObject:[managedObject valueForKey:@"test1_id"] forKey:indexPath];

但是，一般来说，您应该只使用indexPath直接从您为表示表而构建的数据结构中访问对象。

于 2013-08-16T02:34:14.103 回答