UICollectionView not loading on screen - ios

Question

I am trying to create a UICollectionView and its not loading on the screen. In my app delegate I even made it the entry screen and it does not appear just a black screen.
class ChatRoom: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate, UICollectionViewDataSource, UICollectionViewDelegate {
// Struct of Objects
struct Object {
var image: UIImage!
var title: String!
}
// Properties
var object: Object?
var objects: [Object] = []
var picker: UIImagePickerController!
var ref: FIRDatabaseReference?
#IBOutlet weak var collectionView2: UICollectionView!
// Instance of a class
var secondClass : ChatCell?
// Do any additional setup after loading the view, typically from a nib.
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewDidLoad() {
super.viewDidLoad()
// Firebase Data
ref = FIRDatabase.database().reference()
// CollectionView
collectionView2?.delegate = self
collectionView2?.dataSource = self
collectionView2?.reloadData()
// User Logged In
checkIfUserLoggedIn()
picker = UIImagePickerController()
picker?.allowsEditing = false
picker?.delegate = self
picker?.sourceType = .photoLibrary
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! ChatCell
let object = objects[indexPath.row]
cell.chatLabel.text = object.title ?? ""
cell.chatImage.image = object.image ?? UIImage()
cell.layer.borderWidth = 2
cell.layer.borderColor = UIColor.white.cgColor
cell.layer.masksToBounds = true
cell.layer.cornerRadius = 6
return cell
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return objects.count
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let itemWidth = collectionView2.bounds.width
let itemHeight = collectionView2.bounds.height
return CGSize(width: itemWidth, height: itemHeight)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
switch info[UIImagePickerControllerOriginalImage] as? UIImage {
case let .some(image):
object?.image = image
default:
break
}
picker.dismiss(animated: true) {
self.showCellTitleAlert()
}
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
object = nil
dismiss(animated: true) {
self.collectionView2!.reloadData()
}
}
// Alerts
func showCellTitleAlert() {
let alert = UIAlertController(title: "Cell Title", message: nil, preferredStyle: .alert)
alert.addTextField { $0.placeholder = "Enter only 10 characters" }
alert.addAction(UIAlertAction(title: "Cancel", style: .cancel) { _ in
self.object = nil
})
alert.addAction(UIAlertAction(title: "Save", style: .default) { _ in
self.object?.title = (alert.textFields?.first.flatMap { $0.text })!
self.object.flatMap { self.objects.append($0) }
self.collectionView2?.reloadData()
})
present(alert, animated: true, completion: nil)
}
// Create new Cell
#IBAction func didSelectCreateButton() {
object = Object()
present(picker, animated: true, completion: nil)
}

Answer 1

Here the collectionView appears blank because you are not filling the objects array which is the dataSource for the collectionView2.