无法保存核心数据

Question

我尝试在NSFetchedResultsController和不同部分的tableview中保存核心数据。

当我添加数据出现以下错误：

CoreData: error: Serious application error. Exception was caught during Core Data change processing. This is usually a bug within an observer of NSManagedObjectContextObjectsDidChangeNotification. * -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[0] with userInfo (null) Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: ' -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[0] *

First throw call stack: (0x181a05900 0x181073f80 0x1818f41a8 0x1818f4040 0x1000a9068 0x1000aa8d8 0x1835905a8 0x183505080 0x183504f48 0x183495108 0x1819aafc4 0x1819aa7e4 0x1819aa564 0x181a0fde4 0x1818eb0f4 0x1822dad2c 0x18349506c 0x1835098d0 0x18349378c 0x183492240 0x1000aa3a0 0x18672fe50 0x1868b34a4 0x18672fe50 0x18672fdcc 0x186717a88 0x186717bd4 0x18672f6e4 0x18672f314 0x186727e30 0x1866f84cc 0x1866f6794 0x1819bcefc 0x1819bc990 0x1819ba690 0x1818e9680 0x182df8088 0x186760d90 0x10004c23c 0x18148a8b8) libc++abi.dylib: terminating with uncaught exception of type NSException`

我的代码：

MyDetailData* MyDetail = [NSEntityDescription insertNewObjectForEntityForName:@"MyDetailData" inManagedObjectContext:self._privateObjectContext]; 
[MyDetail setKategorie: NSLocalizedString(@"Test", nil)]; 
NSError *error = nil; 
if (![MyDetail.managedObjectContext save:&error]) { 
     NSLog(@"Unresolved error %@, %@", error, [error userInfo]); 
} 

iOS6的下一切正常与代码

这里是我的NSFetchedResultsController

- (NSFetchedResultsController *)fetchedResultsController2 { 

    if (fetchedResultsController2 != nil) { 
     return fetchedResultsController2; 
    } 

    NSFetchRequest *request = [[NSFetchRequest alloc] init]; 
    NSEntityDescription *entity = [NSEntityDescription  entityForName:@"MyDetailData" inManagedObjectContext:_privateObjectContext]; 
    [request setEntity:entity]; 

    NSSortDescriptor *KategorieDescriptor = [[NSSortDescriptor alloc] initWithKey:@"kategorie" ascending:YES]; 
    NSSortDescriptor *oderDescriptor = [[NSSortDescriptor alloc] initWithKey:@"order" ascending:YES]; 
    NSSortDescriptor *nameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES]; 

    NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:KategorieDescriptor,oderDescriptor,nameDescriptor, nil]; 
    [request setSortDescriptors:sortDescriptors]; 


    NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request managedObjectContext:_privateObjectContext sectionNameKeyPath:@"kategorie" cacheName:nil]; 
    aFetchedResultsController.delegate = self; 
    self.fetchedResultsController2 = aFetchedResultsController; 

    return fetchedResultsController2; 

} 

的TableView代表

• numberOfSectionsInTableView
• numberOfRowsInSection
• NSFetchedResultsController didChangeObject - > NSFetchedResultsChangeInsert
• NSFetchedResultsController didChangeSection - > NSFetchedResultsChangeInsert

打来电话，包含正确的信息 - 这里是相关代码：

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView 
{ 
    return [[fetchedResultsController2 sections] count]; 
} 


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section 
{ 
    id <NSFetchedResultsSectionInfo> sectionInfo = [[fetchedResultsController2 sections] objectAtIndex:section]; 
    return [sectionInfo numberOfObjects]; 
} 


- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath { 

    if (userDrivenDataModelChange) return; 

    switch(type) { 
     case NSFetchedResultsChangeInsert: 
      [self.tv insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 
     case NSFetchedResultsChangeDelete: 
      [self.tv deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 

     case NSFetchedResultsChangeUpdate: { 
      [self configureCell:[self.tv cellForRowAtIndexPath:indexPath] atIndexPath:indexPath]; 

      NSString *sectionKeyPath = [controller sectionNameKeyPath]; 
      if (sectionKeyPath == nil) 
       break; 

      NSManagedObject *changedObject = [controller objectAtIndexPath:indexPath]; 
      NSArray *keyParts = [sectionKeyPath componentsSeparatedByString:@"."]; 
      id currentKeyValue = [changedObject valueForKeyPath:sectionKeyPath]; 
      for (int i = 0; i < [keyParts count] - 1; i++) { 
       NSString *onePart = [keyParts objectAtIndex:i]; 
       changedObject = [changedObject valueForKey:onePart]; 
      } 
      sectionKeyPath = [keyParts lastObject]; 
      NSDictionary *committedValues = [changedObject committedValuesForKeys:nil]; 

      if ([[committedValues valueForKeyPath:sectionKeyPath] isEqual:currentKeyValue]) 
       break; 

      NSUInteger tableSectionCount = [self.tv numberOfSections]; 
      NSUInteger frcSectionCount = [[controller sections] count]; 
      if (tableSectionCount != frcSectionCount) { 
       // Need to insert a section 
       NSArray *mysections = controller.sections; 
       NSInteger newSectionLocation = -1; 
       for (id oneSection in mysections) { 
        NSString *sectionName = [oneSection name]; 
        if ([currentKeyValue isEqual:sectionName]) { 
         newSectionLocation = [mysections indexOfObject:oneSection]; 
         break; 
        } 
       } 
       if (newSectionLocation == -1) 
        return; // uh oh 

       if (!((newSectionLocation == 0) && (tableSectionCount == 1) && ([self.tv numberOfRowsInSection:0] == 0))) 
        [self.tv insertSections:[NSIndexSet indexSetWithIndex:newSectionLocation] withRowAnimation:UITableViewRowAnimationFade]; 
       NSUInteger indices[2] = {newSectionLocation, 0}; 
       newIndexPath = [[NSIndexPath alloc] initWithIndexes:indices length:2]; 
      } 


     } 

     case NSFetchedResultsChangeMove: 
      [self.tv deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
          withRowAnimation:NO]; 
      [self.tv insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] 
          withRowAnimation:NO]; 
      break; 
     default: 
      break; 
    } 
} 


- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type { 
    switch(type) { 

     case NSFetchedResultsChangeInsert: 
      if (!((sectionIndex == 0) && ([self.tv numberOfSections] == 1))) 
       [self.tv insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 
     case NSFetchedResultsChangeDelete: 
      if (!((sectionIndex == 0) && ([self.tv numberOfSections] == 1))) 
       [self.tv deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 
     case NSFetchedResultsChangeMove: 
      break; 
     case NSFetchedResultsChangeUpdate: 
      break; 
     default: 
      break; 
    } 
} 

想法怎么回事？

Answer 1

问题解决了。 在

didChangeObject 

在

case NSFetchedResultsChangeMove 

我改了行

[self.tv deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
         withRowAnimation:NO]; 

    [self.tv insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] 
          withRowAnimation:NO]; 

到

if (indexPath && newIndexPath) { 
       [self.tv deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
         withRowAnimation:NO]; 

       [self.tv insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] 
          withRowAnimation:NO]; 
    } else { 
       NSLog(@"A table item was moved"); 
    }