Swift & Parse - Am trying to retrieve a username with a query. - swift

Question

I am trying to retrieve the username belonging to a post. The username can be found in another class however.
These are the two classes I have:
Post
User
I am populating all the information from the Posts class in a UICollectionView but since the username is in the User class my query is not working. Here's my code...
//QUERY LOST
let querylost = PFQuery(className: "Post")
querylost.order(byDescending: "createdAt")
querylost.whereKey("lostfound", equalTo: "lost")
querylost.findObjectsInBackground { (objects, error) in
if let posts = objects {
for post in posts {
self.addresslost.append(post["address"] as! String)
self.breedlost.append(post["breed"] as! String)
self.phonelost.append(post["phone"] as! String)
self.imageFileslost.append(post["imageFile"] as! PFFile)
//HERE'S THE PROBLEM - username is in User Class
self.usernames.append(self.queryusers[post["userid"] as! String]!)
//ENDS here
self.lostCollectionView.reloadData()
self.refresherLost.endRefreshing()
}
}
}
//TO SHOW DATA
scrollView.delegate = self
lostCollectionView.delegate = self
lostCollectionView.dataSource = self
}

Answer 1

Instead of using the userid field, you should create a pointer to put on your Post object instead. Then you can access the User object via the Post object.
Your code would look something like this:
let querylost = PFQuery(className: "Post")
querylost.order(byDescending: "createdAt")
querylost.include("user")
querylost.whereKey("lostfound", equalTo: "lost")
querylost.findObjectsInBackground { (objects, error) in
if let posts = objects {
for post in posts {
self.addresslost.append(post["address"] as! String)
self.breedlost.append(post["breed"] as! String)
self.phonelost.append(post["phone"] as! String)
self.imageFileslost.append(post["imageFile"] as! PFFile)
//unwrap the user pointer, and get the username
if let user = post["user"] as? PFUser, let username = user.username{
self.usernames.append(username)
}
//ENDS here
self.lostCollectionView.reloadData()
self.refresherLost.endRefreshing()
}
}
}