Question

我有一个表格视图，可以在按下按钮时添加行。对于每一行，行按字符串itmeNo按升序编号。我的问题是当用户删除一行时，数字不再有序。

即1,2,3,4,5，

如果用户删除第3行和第4行，则编号为

1,2,5-

我对如何按数字排序有点困惑？我有[self.observations count] + 1];我可以改变这个，itemNo总是按数字递增

总之，我总是希望我的表视图行数字串始终按顺序编号

到目前为止，我已经在删除方法中尝试了[self.tableView reloadData];并使用允许重新排序表视图的方法。

 - (void)addObservationButtonPressed:(id)sender
{
LogCmd();
Observation *observation = [[ICObservationManager manager] newObservation];
observation.createdAt = [NSDate date];
observation.modifiedAt = [NSDate date];
observation.certificate = self.certificate;
observation.itemNo = [NSString stringWithFormat:@"%d", [self.observations count] + 1];
[self.certificate addObservationsObject:observation];
[self loadData];
[self.tableView reloadData];
[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:self.observations.count-1 inSection:0] atScrollPosition:UITableViewScrollPositionBottom animated:YES];
}


 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
 {
return [self.certificate.observations count];
}



 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = @"ObservationsCellIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
Observation *observation = [self.observations objectAtIndex:indexPath.row];
NSString *itemLabel = [NSString stringWithFormat:@"%@. %@",
                       observation.itemNo,
                       (observation.item.length ? observation.item : @"No description")];
cell.textLabel.text = itemLabel;

return cell;
}

 //Delete observations

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
 {

if (editingStyle == UITableViewCellEditingStyleDelete) {
    [self.managedObjectContext deleteObject:[self.observations objectAtIndex:indexPath.row]];
    [self.appDelegate saveContext];
    [self.observations removeObjectAtIndex:indexPath.row];
    [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];

 }

}

Answer 1

这是代码： -

Observation *observation = [self.observations objectAtIndex:[self.observations count]-1];
int lastValue = [observation.itemNo intValue];
lastValue++;

lastValue是您可以使用的最大值

希望它可以帮到你

Answer 2

试试此代码

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
 {

if (editingStyle == UITableViewCellEditingStyleDelete) {
    [self.managedObjectContext deleteObject:[self.observations objectAtIndex:indexPath.row]];
    [self.appDelegate saveContext];
    [self.observations removeObjectAtIndex:indexPath.row];

//need to add these lines
 NSSortDescriptor *sortByUploaded =[NSSortDescriptor sortDescriptorWithKey:@"itmeNo"ascending:YES];

  NSArray *sortDescriptorArr = [NSArray arrayWithObjects:sortByUploaded,nil];

 self.observations = [NSMutableArray arrayWithArray:[self.observations sortedArrayUsingDescriptors:sortDescriptorArr]];


    [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];

 }

}

如果它不起作用，请告诉我

Answer 3

当您从UITableView删除行时，只需将其重新排序为@ rohit 所需的订单，然后删除该行并根据订单重新加载您的表。希望这会有所帮助。

删除行后如何以数字方式对表视图编号字符串进行排序

3 个答案: