断言失败 - [XMPPRoster initWithRosterStorage：dispatchQueue：]

Question

[userArry removeAllObjects];//mutable array
NSManagedObjectContext *Context = [_xmppRosterStorage mainThreadManagedObjectContext];        
NSFetchRequest *request = [[NSFetchRequest alloc]initWithEntityName:@"XMPPUserCoreDataStorageObject"];
NSError *error;
NSArray *ary = [Context executeFetchRequest:request error:&error];

for (NSManagedObject *obj in ary)
{
    NSLog(@"%@",[obj valueForKey:@"jid"]);
    NSDictionary *dic = [[NSDictionary alloc]initWithObjectsAndKeys:[obj valueForKey:@"jid"],@"jid",[obj valueForKey:@"displayName"],@"displayName",[obj valueForKey:@"jidStr"] ,@"jidStr",[obj valueForKey:@"photo"],@"photo",nil];

    [userArry addObject:dic];
}

if (userArry.count>0)
{
    [self performSegueWithIdentifier:@"login" sender:nil];
}

  

应用程序崩溃执行segue时出现错误断言失败 - [XMPPRoster initWithRosterStorage：dispatchQueue：]，Pods / XMPPFramework / Extensions / Roster / XMPPRoster.m:63    ***因未捕获的异常终止应用程序＆＃39; NSInternalInconsistencyException＆＃39;，原因：＆＃39;无效的参数不满足：storage！= nil＆＃39;

请帮助我，我不熟悉XMPP