Question

我经常搜索这个错误，但无法找到解决方案。

我有我的托管对象：

lazy var managedObjectContext: NSManagedObjectContext = {
    let coordinator = self.persistentStoreCoordinator
    var managedObjectContext = NSManagedObjectContext(concurrencyType: .MainQueueConcurrencyType)
    managedObjectContext.persistentStoreCoordinator = coordinator
    return managedObjectContext
}()

我有一个Singleton类

lazy var managedObjectContext : NSManagedObjectContext? = {

    if let appDelegate = UIApplication.sharedApplication().delegate as? AppDelegate {
            return appDelegate.managedObjectContext
    }
    return nil

}()

每当我从数据库

更新/删除/加载数据时，我都会有一个被称为大量时间的方法

class func LoadDatabase(tableName: String, predicateString: String, predicateIntValue: Int) -> [AnyObject]? {

        do {
            let managedObjectContext = Singleton.sharedInstance.managedObjectContext

            if managedObjectContext == nil {
                return nil
            }

            let fReq: NSFetchRequest = NSFetchRequest(entityName: tableName)
            if predicateString != "" {
                fReq.predicate = NSPredicate(format: predicateString,  predicateIntValue)
            }

            var result: [AnyObject]
            do {
                if managedObjectContext == nil {
                    return nil
                }
                result = try managedObjectContext!.executeFetchRequest(fReq)
            } catch {
                return nil
            }

            // update exist event
            if
                result.count != 0 {
                return result
            }
        } catch let error1 as NSError {
            print("No values to load for table: \(error1)")
        }
        return nil
    }

我认为我在并发访问方面存在问题。当应用程序启动时，它会通过异步请求来更新数据库。但我也从varius控制器调用LoadDatabase方法。一旦异步调用完成了更新datable，它就会调用另一种方法来删除远程数据库中不再存在的数据。

这就是我得到的。这不会永远发生。

我尝试更改为MainQueueConcurrency，但现在我也遇到了这个错误：

2016-03-20 21:27:01.371 Tamil League[1070:245784] CoreData: error: Serious application error.  Exception was caught during Core Data change processing.  This is usually a bug within an observer of NSManagedObjectContextObjectsDidChangeNotification.  -[__NSCFSet addObject:]: attempt to insert nil with userInfo (null)
2016-03-20 21:27:01.371 Tamil League[1070:245784] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFSet addObject:]: attempt to insert nil'
*** First throw call stack:
(0x24a9e2eb 0x2426adff 0x24a9e231 0x249e7fe5 0x261eb683 0x261ea063 0x261e2dfb 0x24a60b21 0x24a5ee17 0x24a5f255 0x249b1bb9 0x249b19ad 0x25c2baf9 0x28c9dfb5 0xa6d5c 0x24664873)
libc++abi.dylib: terminating with uncaught exception of type NSException

有谁知道如何解决这个问题？

使用EXC_BAD_ACCESS

0 个答案: