Question

您好我很抱歉我是初学者。我在UILabel中有一个表行值，它们加载了Core Data，我需要以某种方式比较并找到最大值，从而将背景颜色更改为红色UILabel。我对每个答案都很满意。

 - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
   {
     // Return the number of sections.
        return 1;
   }

 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
   {
     // Return the number of rows in the section.
        return self.voda.count;
    }

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

        // Configure the cell...
         NSManagedObject *vodapocet = [self.voda objectAtIndex:indexPath.row];

         UILabel *dLabel= (UILabel *)[cell viewWithTag:10];
         [dLabel setText:[NSString stringWithFormat:@"%@" ,[vodapocet valueForKey:@"datum"]]];

         UILabel *sLabel= (UILabel *)[cell viewWithTag:20];
         [sLabel setText:[NSString stringWithFormat:@"%@" ,[vodapocet valueForKey:@"spotreba" ]]];
         [sLabel setBackgroundColor:[UIColor greenColor]];

         UILabel *cLabel= (UILabel *)[cell viewWithTag:30];
         [cLabel setText:[NSString stringWithFormat:@"%@" ,[vodapocet valueForKey:@"cena"]]];

          return cell;
  }

 - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath{
    return YES;
 }

 - (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
   NSManagedObjectContext *context = [self managedObjectContext];

  if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete object from database
    [context deleteObject:[self.voda objectAtIndex:indexPath.row]];

    NSError *error = nil;
    if (![context save:&error]) {
        NSLog(@"Can't Delete! %@ %@", error, [error localizedDescription]);
        return;
    }

        // Remove device from table view
    [self.voda removeObjectAtIndex:indexPath.row];
    [self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]   withRowAnimation:UITableViewRowAnimationFade];
  }
 }

Answer 1

获取最大值：

NSNumber *maxSpotreba = [self.voda valueForKeyPath:@"@max.spotreba"];

然后在cellForRowAtIndexPath中您可以将此数字与当前行的数字进行比较，以确定要执行的操作。

从项目UitableView获取价值

1 个答案: