Query Error while trying to populate data from Parse into CollectionView - ios

Question

So I am making an app, where the home view will show two sets of collection views. I am trying to filter how the information is sent and distributed into these two collectionviews based on a parameter from the image posted. My app is crashing down with this error.
Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value
Below I'm putting all my code.
import UIKit
import Parse
class HomeViewController: UIViewController{
//VAR ARRAYS - LOST
var userslost = [String: String]()
var addresslost = [String]()
var breedlost = [String]()
var phonelost = [String]()
var usernameslost = [String]()
var imageFileslost = [PFFile]()
//VAR ARRAYS - FOUND
var usersfound = [String: String]()
var addressfound = [String]()
var breedfound = [String]()
var phonefound = [String]()
var usernamesfound = [String]()
var imageFilesfound = [PFFile]()
//#IBOUTLETS
#IBOutlet weak var scrollView: UIScrollView!
#IBOutlet weak var lostView: UIView!
#IBOutlet weak var foundView: UIView!
#IBOutlet weak var lostCollectionView: UICollectionView!
#IBOutlet weak var foundCollectionView: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
//QUERY LOST
let querylost = PFQuery(className: "Post")
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.usernameslost.append(self.userslost[post["userid"] as! String]!)
self.imageFileslost.append(post["imageFile"] as! PFFile)
}
}
}
// QUERY FOUND
let queryfound = PFQuery(className: "Post")
queryfound.whereKey("lostfound", equalTo: "found")
queryfound.findObjectsInBackground { (objects, error) in
if let posts = objects {
for post in posts {
self.addressfound.append(post["address"] as! String)
self.breedfound.append(post["breed"] as! String)
self.usernamesfound.append(self.userslost[post["userid"] as! String]!) **--> ERROR IS HERE**
self.imageFilesfound.append(post["imageFile"] as! PFFile)
}
}
}
//TO SHOW DATA
scrollView.delegate = self
lostCollectionView.delegate = self
lostCollectionView.dataSource = self
foundCollectionView.delegate = self
foundCollectionView.dataSource = self
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
// START OF EXTENSIONS FOR COLLECTION VIEWS
extension HomeViewController: UICollectionViewDelegate, UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
if collectionView == self.lostCollectionView {
return addresslost.count
//DUDA #2
}
else {
return addressfound.count
//DUDA #2
}
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if collectionView == self.lostCollectionView {
let cell: LostCollectionViewCell = collectionView.dequeueReusableCell(withReuseIdentifier: "Lostcell", for: indexPath) as! LostCollectionViewCell
//TIENES QUE IGUALAR LOS #IBOUTLETS DEL CELL (SPECIFICOS A LOST) Y IGUALARLOS CON EL ARRAY DE PARSE QUE PUEDES ENCONTRAR EN VARS ARRIBA
cell.adressLostLabel.text = addresslost[indexPath.row]
cell.breedLostLabel.text = breedlost[indexPath.row]
cell.phoneLostLabel.text = phonelost[indexPath.row]
imageFileslost[indexPath.row].getDataInBackground { (data, error) in
if let imageData = data {
if let imageToDisplay = UIImage(data: imageData) {
cell.postedImage.image = imageToDisplay
}
}
}
return cell
}
else {
let cell: FoundCollectionViewCell = collectionView.dequeueReusableCell(withReuseIdentifier: "Foundcell", for: indexPath) as! FoundCollectionViewCell
cell.adressFoundLabel.text = addressfound[indexPath.row]
cell.breedFoundLabel.text = breedfound[indexPath.row]
cell.phoneFoundLabel.text = phonefound[indexPath.row]
imageFilesfound[indexPath.row].getDataInBackground { (data, error) in
if let imageData = data {
if let imageToDisplay = UIImage(data: imageData) {
cell.postedImage.image = imageToDisplay
}
}
}
return cell
}
}
}
//SCROLL
extension HomeViewController: UIScrollViewDelegate{
func scrollViewDidScroll(_ scrollView: UIScrollView) {
print(scrollView)
}
}
Error can be found in this line of code:
self.usernamesfound.append(self.userslost[post["userid"] as! String]!)

Answer 1

Please insert this in, it should work:
self.usernamesfound.append(self.userslost[post["userid"] as? String]?)