更新无效：部分中的行数无效

Question

我正在使用 Microsoft Azure services 进行一个项目。在删除行时出现此错误：

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 0.  The number of rows contained in an existing section after the update (2) must be equal to the number of rows 
contained in that section before the update (2), plus or minus the number of rows inserted or deleted from that section (0 inserted, 1 deleted) and plus or minus the number of rows moved into or out of that section (0 moved in, 0 moved out).

table 加载和删除行的代码如下：

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
        return 3;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    //medicine list
    if (section == 0) {
        NSArray *sectionInfo = [self.fetchedResultsController1 fetchedObjects];
        return [sectionInfo count];

    }
    //allergy list
    else if (section == 1) {
        NSArray *sectionInfo = [self.fetchedResultsController2 fetchedObjects];
        return [sectionInfo count];

    }
    //notes list
    else if (section == 2){
        NSArray *sectionInfo = [self.fetchedResultsController3 fetchedObjects];
        return [sectionInfo count];
    }
    else
        return 0;
 }

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

    static NSString *cellIdentifier = @"mcell";
    MedicationTableViewCell *cell = (MedicationTableViewCell *)    [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];

    //  Add utility buttons 
    NSMutableArray *rightUtilityButtons = [NSMutableArray new];
    [rightUtilityButtons sw_addUtilityButtonWithColor: [UIColor colorWithRed:1.0f green:0.231f blue:0.188 alpha:1.0f] title:@"Delete"];

    switch (indexPath.section) {
        case 0: {
            NSManagedObject *item = [self.fetchedResultsController1 objectAtIndexPath:indexPath];
            cell.textLabel.text = [item valueForKey:@"name"];
            break;
        }
        case 1: {
            NSManagedObject *item = [self.fetchedResultsController2 objectAtIndexPath:[NSIndexPath indexPathForRow:indexPath.row inSection:0]];
            cell.textLabel.text = [item valueForKey:@"name"];
            break;
        }
        case 2: {
            NSManagedObject *item = [self.fetchedResultsController3 objectAtIndexPath: [NSIndexPath indexPathForRow:indexPath.row inSection:0]];
            cell.textLabel.text = [item valueForKey:@"title"];
            break;
        }
        default:
            break;
    }
    cell.rightUtilityButtons = rightUtilityButtons;
    cell.delegate = self;

    return cell;
}

- (void)swipeableTableViewCell:(SWTableViewCell *)cell didTriggerRightUtilityButtonWithIndex:(NSInteger)index {

 // Delete button is pressed
 NSIndexPath *cellIndexPath = [self.medicationsTableView indexPathForCell:cell];

 //fetchingg data from local store first
 NSManagedObject *item = [self.fetchedResultsController1 objectAtIndexPath:[NSIndexPath indexPathForRow:cellIndexPath.row inSection:0]];

   NSMutableArray *keys = [[NSMutableArray alloc] initWithObjects:@"id", @"name", @"userId", nil];
   NSMutableArray *values = [[NSMutableArray alloc] initWithObjects: [item valueForKey:@"id"], [item valueForKey:@"name"], [item valueForKey:@"userId"], nil];

    //creating dictionary of data
    NSDictionary *dict = [[NSDictionary alloc] initWithObjects:values forKeys:keys];

    //calling delete fucntion
    [self.authService deleteItem:self.syncTable withDict:dict completion:^{
    //removing row from table view
    [self.medicationsTableView reloadData];
    [self.medicationsTableView deleteRowsAtIndexPaths:@[cellIndexPath] withRowAnimation:UITableViewRowAnimationRight];
      }];
      break;
}

请告诉我哪里错了。提前致谢!!!!

Answer 1

在- (void)swipeableTableViewCell: didTriggerRightUtilityButtonWithIndex:

您需要删除

[self.medicationsTableView reloadData];

或

[self.medicationsTableView deleteRowsAtIndexPaths:@[cellIndexPath] withRowAnimation:UITableViewRowAnimationRight];

因为在调用 reloadData 时的第一行，它使用新的数据源重新加载表视图，并再次调用 deleteRowsAtIndexPaths 试图删除已通过调用 reloadData 删除的行。

Answer 2

重要的是你需要使用

[self.medicationsTableView reloadData];

或

[self.medicationsTableView deleteRowsAtIndexPaths:@[cellIndexPath] withRowAnimation:UITableViewRowAnimationRight];

原因是，当调用 tableview's reload data 时，从数据源中删除的行被删除，之后当为相同的 index path 调用删除行 api 时（该行已被删除导致问题）

同样在从 table 中删除行之前从数据源 (self.fetchedResultsController1) 中删除对象并调用

[self.medicationsTableView deleteRowsAtIndexPaths:@[cellIndexPath] withRowAnimation:UITableViewRowAnimationRight];

上面一行的删除动画完成后就可以调用了（但不是必须的）

[self.medicationsTableView reloadData];

更新无效：部分中的行数无效

Invalid update: invalid number of rows in section

xcode

core-data

uitableview

ios

azure-mobile-services