Question

在阅读了与此相关的几个问题后，我可以使用该功能。但是我的列表很长且可滚动，所以当我向上和向下滚动时，选中的复选标记就到处都是。 selectedIndexes是NSMutableArray。有什么想法吗？

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *selectedCell = [tableView cellForRowAtIndexPath:indexPath];

    if ([selectedCell accessoryType] == UITableViewCellAccessoryNone) {
        [selectedCell setAccessoryType:UITableViewCellAccessoryCheckmark];
        [selectedIndexes addObject:[NSNumber numberWithInt:indexPath.row]];

    } 
    else {
        [selectedCell setAccessoryType:UITableViewCellAccessoryNone];
        [selectedIndexes removeObject:[NSNumber numberWithInt:indexPath.row]];

    }

    [tableView deselectRowAtIndexPath:indexPath animated:NO];

}

在我cellForRowAtIndexPath:我有以下检查。

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

    static NSString *CellIdentifier = @"CustomCell";

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

    // Configure the cell...
    NSDictionary *dictionary = [natures objectAtIndex:indexPath.section];
    NSArray *array = [dictionary objectForKey:@"Name"];
    NSString *cellValue = [array objectAtIndex:indexPath.row];
    cell.textLabel.text = cellValue;

    for (int i = 0; i < selectedIndexes.count; i++) {
        NSUInteger num = [[selectedIndexes objectAtIndex:i] intValue];

        if (num == indexPath.row) {
            [cell setAccessoryType:UITableViewCellAccessoryCheckmark];
        }
        else {
            [cell setAccessoryType:UITableViewCellAccessoryNone];
        }

    }

    return cell;
}

Answer 1

您需要viewDidLoad

进行多项选择

self.tableView.allowsMultipleSelection = YES;

和

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *tableViewCell = [tableView cellForRowAtIndexPath:indexPath];
    tableViewCell.accessoryView.hidden = NO; 
    // if you don't use a custom image then tableViewCell.accessoryType = UITableViewCellAccessoryCheckmark;
}

- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *tableViewCell = [tableView cellForRowAtIndexPath:indexPath];
    tableViewCell.accessoryView.hidden = YES;
    // if you don't use a custom image then tableViewCell.accessoryType = UITableViewCellAccessoryNone;
}

Answer 2

您需要将cellForRowAtIndexPath修改为以下内容：

// Assume cell is not checked -- if it is the loop below will check it.
[cell setAccessoryType:UITableViewCellAccessoryNone];
for (int i = 0; i < selectedIndexes.count; i++) {
        NSUInteger num = [[selectedIndexes objectAtIndex:i] intValue];

        if (num == indexPath.row) {
            [cell setAccessoryType:UITableViewCellAccessoryCheckmark];
            // Once we find a match there is no point continuing the loop
            break;
        }
    }

您需要执行此操作，因为可重复使用的单元格可能设置了复选标记 - 因此您需要清除它。希望这会有所帮助。

顺便说一句，使用NSSet可能是更优雅的解决方案！

Answer 3

无需维护用于存储所选行的单独数组。使用本机方法indexPathsForSelectedRows来获取选定的单元indexPath数组。只需在cellForRow方法中检查arrayContains当前的IndexPath，如下所示：

NSArray *indexPaths = [tableView indexPathsForSelectedRows];

if ([indexPaths containsObject:indexPath]) {
    cell.accessoryType = UITableViewCellAccessoryCheckmark;
}else {
    cell.accessoryType = UITableViewCellAccessoryNone;
}

#pragma mark- select/deselect 

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    [[self.tableView cellForRowAtIndexPath:indexPath] setAccessoryType:UITableViewCellAccessoryCheckmark];
}

-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath {
    [[self.tableView cellForRowAtIndexPath:indexPath] setAccessoryType:UITableViewCellAccessoryNone];
}

UITableView多个复选标记选择

3 个答案: