'Tried to save an object with a new, unsaved child.' swift parse - parse-platform

Question

This is my code :
userEmployer.signUpInBackgroundWithBlock { (success, error) -> Void in
if error != nil {
let errorString = error?.userInfo["error"] as! String
} else {
var queryRole = PFRole.query()
queryRole?.whereKey("name", equalTo: "Employer")
queryRole?.getFirstObjectInBackgroundWithBlock({ (roleObject, error) -> Void in
if error == nil{
var roleToAddUser = roleObject as! PFRole
roleToAddUser.users.addObject(PFUser.currentUser()!)
roleToAddUser.saveInBackground()
}// end of it
})// end of query
}//end of else
}//end of signup
It's really weird because I have the same template of code for registering a different role and it works properly. It keeps throwing
'Tried to save an object with a new, unsaved child.'
I don't understand why it's throwing an error.
First throw call stack:
(
0 CoreFoundation 0x0000000106cddf45 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000106755deb objc_exception_throw + 48
2 CoreFoundation 0x0000000106cdde7d +[NSException raise:format:] + 205
3 post 0x0000000104ec93e2 -[PFPointerObjectEncoder encodeParseObject:] + 108
4 post 0x0000000104ec8874 -[PFEncoder encodeObject:] + 113
5 post 0x0000000104e97e3f __129+[PFRESTQueryCommand findCommandParametersWithOrder:conditions:selectedKeys:includedKeys:limit:skip:extraOptions:tracingEnabled:]_block_invoke97 + 1808
6 CoreFoundation 0x0000000106c4acb5 __65-[__NSDictionaryI enumerateKeysAndObjectsWithOptions:usingBlock:]_block_invoke + 85
7 CoreFoundation 0x0000000106c4abbd -[__NSDictionaryI enumerateKeysAndObjectsWithOptions:usingBlock:] + 237
8 post 0x0000000104e9764d +[PFRESTQueryCommand findCommandParametersWithOrder:conditions:selectedKeys:includedKeys:limit:skip:extraOptions:tracingEnabled:] + 911
9 post 0x0000000104e9727c +[PFRESTQueryCommand findCommandParametersForQueryState:] + 296
10 post 0x0000000104e96d2f +[PFRESTQueryCommand findCommandForQueryState:withSessionToken:] + 79
11 post 0x0000000104ea8c89 __78-[PFQueryController findObjectsAsyncForQueryState:withCancellationToken:user:]_block_invoke + 106
12 post 0x0000000104e4dd0e __37+[BFTask taskFromExecutor:withBlock:]_block_invoke + 78
13 post 0x0000000104e4f470 __55-[BFTask continueWithExecutor:block:cancellationToken:]_block_invoke_2 + 112
14 libdispatch.dylib 0x0000000108c18e5d _dispatch_call_block_and_release + 12
15 libdispatch.dylib 0x0000000108c3949b _dispatch_client_callout + 8
16 libdispatch.dylib 0x0000000108c21bef _dispatch_root_queue_drain + 1829
17 libdispatch.dylib 0x0000000108c214c5 _dispatch_worker_thread3 + 111
18 libsystem_pthread.dylib 0x0000000108f81a9d _pthread_wqthread + 729
19 libsystem_pthread.dylib 0x0000000108f7f3dd start_wqthread + 13
)
libc++abi.dylib: terminating with uncaught exception of type NSException
added info: When I tap the register button it goes to the tableviewcontroller, I tried removing the segue and it registered the user. seems like the error is inside my tableviewconller. this is the code inside.
//creating a pointer
var userPointer = PFUser.objectWithoutDataWithObjectId(PFUser.currentUser()?.objectId)
query.whereKey("postedBy", equalTo: userPointer)
query.orderByDescending("createdAt")
if PFUser.currentUser() != nil {//added1
let objects = query.findObjects()
for object in (objects as? [PFObject])!{
//print(object.objectId)
self.dataSource.append(object)
self.createdByDate.append((object.objectForKey("closingDate") as? NSDate)!)
print(dataSource)
print(createdByDate)
}
let itemArr:PFObject = self.dataSource[indexPath.row] as! PFObject
cell?.companyPostLabel.text = (PFUser.currentUser()?.objectForKey("companyName")!.capitalizedString)! as String
cell?.occupationPostLabel.text = itemArr["occupation"]!.capitalizedString as! String
let companyImage: PFFile?
companyImage = PFUser.currentUser()?.objectForKey("profileImageEmployer") as! PFFile
companyImage?.getDataInBackgroundWithBlock({ (data, error) -> Void in
if error == nil{
cell?.companyLogoImage.image = UIImage(data: data!)
}
})
} else {
print("user not found")
}
let dateArr = createdByDate[indexPath.row]
var dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy'-'MM'-'dd' : 'hh':'mm'"
var strDate = dateFormatter.stringFromDate(dateArr)
cell?.closingDateLabel .text = strDate
edit 2 : This line is throwing the error
let query = PFQuery(className: "JobPost")
//creating a pointer
var userPointer = PFUser.objectWithoutDataWithObjectId(PFUser.currentUser()?.objectId)
query.whereKey("postedBy", equalTo: userPointer)
let objects = query.findObjects()
return (objects?.count)!

Answer 1

Make sure your currentUser is saved first. You can check with it's objectId.
if ([PFUser currentUser].objectId == nil)
[[PFUser currentUser] saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
// Perform queryRole
}];
else
// Perform queryRole directly