我已经设法简化了编码以重现错误,并希望与其他人一起尝试这一点的第二意见.

这是一个完整性检查,因为我怀疑iOS 7引入的核心数据问题,因为这在iOS 6中运行正常.

首先,启动一个新的核心数据项目并创建这个模型……

属性’current’是可选的布尔值.一对多关系是有序关系,创建NSOrderedDataset.

现在为应用添加几个按钮;第一个创建数据(一个项目和两个相关的’图纸’),第二个交换两个图纸,然后在第一个图纸中设置一个属性.

这是代码……

-(IBAction)onTestButton:(id)sender
{
    id delegate = [[UIApplication sharedApplication]delegate];
    NSManagedObjectContext *managedObjectContext = [delegate managedObjectContext];
 
    self.project = [NSEntityDescription insertNewObjectForEntityForName:@"Project" inManagedObjectContext:managedObjectContext];
    Drawing *drawing1 = [NSEntityDescription insertNewObjectForEntityForName:@"Drawing" inManagedObjectContext:managedObjectContext];
    Drawing *drawing2 = [NSEntityDescription insertNewObjectForEntityForName:@"Drawing" inManagedObjectContext:managedObjectContext];
 
    NSMutableOrderedSet* tempSet = [NSMutableOrderedSet orderedSetWithOrderedSet:self.project.drawings];
    [tempSet addObject:drawing1];
    [tempSet addObject:drawing2];
    self.project.drawings = tempSet;
 
    [self save];
}
 
-(IBAction)onTestButton2:(id)sender
{
    NSMutableOrderedSet *exchange = [self.project mutableOrderedSetValueForKey:@"drawings"];
    [exchange exchangeObjectAtIndex:0 withObjectAtIndex:1];
    self.project.drawings = exchange;
 
    [self save];
 
    Drawing *drawing = [self.project.drawings objectAtIndex:0];
 
    BOOL current = [drawing.current boolValue];
    drawing.current = [NSNumber numberWithBool:!current];
 
    [self save];
}
 
-(void)save
{
    id delegate = [[UIApplication sharedApplication]delegate];
    NSManagedObjectContext *managedObjectContext = [delegate managedObjectContext];
    NSError *error = nil;
 
    if( ![managedObjectContext save:&error] )
    {
        NSLog(@"%@ Save: Unresolved Error on Save %@",error,[error userInfo] );
        abort();
    }
}

现在,按第一个测试按钮进行测试.这会设置数据.

然后按第二个测试按钮……一切OK！

现在再次按下第二个测试按钮并弹出.您应该得到类似于此的NSMergeConflict错误….

Save: Unresolved Error on Save {
conflictList = (
“NSMergeConflict (0x8a7d0b0) for NSManagedObject (0x8bedfa0) with objectID ‘0x8bd9340
‘ with
oldVersion = 1 and newVersion = 2 and old object snapshot = {\n
current = \”\”;\n project = \”0x8bc3f50
\”;\n}
and new cached row = {\n current = \”\”;\n project =
\”0x8aa88c0
\”;\n}”
);

我从错误中注意到我的Project对象已经改变.但是,这是使用主应用程序上下文的单线程应用程序.

我花了太长时间在这上面,并希望其他人就问题所在地发表评论.这是一个核心数据错误,还是我是一个正确的’傻瓜’？

非常感谢

/适合