Question

我在CoreData版本迁移中遇到了一个奇怪的错误。它崩溃了，我绝对难倒。我在xcdatamodel的第2版中为一个子实体添加了两个新属性，并将其设置为当前版本。创建持久性存储协调器的代码如下所示：

 NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"MyModel" withExtension:@"momd"];
    self.mainModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
    self.mainQueueManagedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
    self.persistentStoreCoordinator = [self storeCoordinatorForDB:@"MyDB.sqlite" objectModel:self.mainModel managedObjectContext:self.mainQueueManagedObjectContext];

- (NSPersistentStoreCoordinator *)storeCoordinatorForDB:(NSString *)dbName objectModel:(NSManagedObjectModel *)model managedObjectContext:(NSManagedObjectContext *)moc {
    NSFileManager *fm = [NSFileManager defaultManager];
    NSURL *storeURL = [[fm URLsForDirectory:NSApplicationSupportDirectory
                              inDomains:NSUserDomainMask] lastObject];
    if (!storeURL) {
        return nil;
    }
    else {
        NSError *createError = nil;
        BOOL createSuccess = [fm createDirectoryAtURL:storeURL withIntermediateDirectories:YES attributes:nil error:&createError];
        if (!createSuccess) {
            NSLog(@"Dir creation error: %@", createError);
        }
    }
    storeURL = [storeURL URLByAppendingPathComponent:dbName];
    NSURL *mainBundleDBURL = [[[NSBundle mainBundle] bundleURL] URLByAppendingPathComponent:dbName];
    NSError *copyError = nil;
    BOOL copySuccess = [fm copyItemAtURL:mainBundleDBURL toURL:storeURL error:&copyError];
    if (!copySuccess) {
        NSLog(@"File copy error: %@", copyError);
    }

    NSError *error = nil;
    NSPersistentStoreCoordinator *coordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
    moc.persistentStoreCoordinator = coordinator;
    NSPersistentStore *ps = [coordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:@{
                       NSMigratePersistentStoresAutomaticallyOption:@(YES),
                             NSInferMappingModelAutomaticallyOption:@(YES)
                             } error:&error];
    if (!ps) {
        NSLog(@"Unresolved error adding persistent store: %@", error);
        return nil;
    }
    return coordinator;
}

MyDB.sqlite是先前版本的xcdatamodel中预先提供的CoreData文件。

这导致EXC_BAD_ACCESS（据我所知）绝对虚假的地址，例如。 0x0或0x16）

生成的堆栈跟踪是：

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000000
Crashed Thread:  0

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libobjc.A.dylib                 0x3b2f95d6 objc_msgSend + 22
1   CoreData                        0x333e5274 -[NSFetchedPropertyDescription copyWithZone:] + 140
2   CoreData                        0x333d8f62 -[NSEntityDescription copyWithZone:] + 682
3   CoreData                        0x333d8e70 -[NSEntityDescription copyWithZone:] + 440
4   CoreData                        0x3340f4a8 -[NSManagedObjectModel copyWithZone:] + 340
5   CoreData                        0x3341d20e -[NSMigrationManager initWithSourceModel:destinationModel:] + 178
6   CoreData                        0x3346dc5e -[NSStoreMigrationPolicy managerForSourceModel:destinationModel:error:] + 390
7   CoreData                        0x3346f060 -[NSStoreMigrationPolicy(InternalMethods) _gatherDataAndPerformMigration:] + 1596
8   CoreData                        0x3339235c -[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:] + 3340
9   ActorsNetwork                   0x000ba072 -[DataStore storeCoordinatorForDB:objectModel:managedObjectContext:] (DataStore.m:69)

任何人都知道发生了什么或有用的提示如何调试这个？我已经尝试了仪器分配，但没有进一步。

[求助]有点儿。我在模型中有一个获取的属性定义。删除它修复了导入崩溃。

在addPersistentStoreWithType中，CoreData版本迁移失败：配置：URL：options：error：

0 个答案: