Presenting image picker using TapGesture on UIImageView - swift3

Question

I have a View with an UIImageView that I want to be 'selectable' so that the user can pick a new image.
The function for picking the new image is in the Controller.
Question
How do I call the myDatasourceController.handleTap() function by pressing the ImageView, so that the image picker is presented?
This is an example of my current setup
View
class myView: UICollectionViewCell {
lazy var profileImageView: UIImageView = {
let iv = UIImageView()
iv.isUserInteractionEnabled = true
iv.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(myDatasourceController.handleTap)))
return iv
}()
}
Controller
class myDatasourceController: UICollectionViewController,
UICollectionViewDelegateFlowLayout, UIImagePickerControllerDelegate,
UINavigationControllerDelegate {
func handleTap(){
let imagePickerController = UIImagePickerController()
imagePickerController.delegate = self
imagePickerController.allowsEditing = true
present(imagePickerController, animated: true, completion: nil)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// logic for picking the image
dismiss(animated: true, completion: nil)
}
}
This setup currently throws the error
unrecognized selector sent to instance 0x7f9163d493f0
which has led me to try various combinations of
handleTap(_:)
handleTap(sender: UITapGestureRecogniser)
/// etc
but I can't get any of them to work. How should I be constructing my View, Controller, and the interaction between them to present the image picker?

Answer 1

Use Like this
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(RegisterViewController. handleTap(gesture:)))
func handleTap(gesture: UIGestureRecognizer) {
// if the tapped view is a UIImageView then set it to imageview
if (gesture.view as? UIImageView) != nil {
print("Image Tapped")
picker.allowsEditing = false
picker.sourceType = .photoLibrary
picker.mediaTypes = UIImagePickerController.availableMediaTypes(for: .photoLibrary)!
present(picker, animated: true, completion: nil)
}
}

Answer 2

Use like this :
myDatasourceController.handleTap()
In your code :
iv.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(myDatasourceController.handleTap())))

Answer 3

The key to the solution is to implement a protocol / delegate, as suggested by #Akis
I've uploaded the full project to my github account. The key code is copied here.
View Controller
protocol ImagePickerDelegate: class {
func loadImagePicker()
}
class HomeViewController: UICollectionViewController, UICollectionViewDelegateFlowLayout, UIImagePickerControllerDelegate, UINavigationControllerDelegate, ImagePickerDelegate {
let cellId = "cellId"
func loadImagePicker(){
print(" -- image picker -- ")
// load image picker
let imagePickerController = UIImagePickerController()
imagePickerController.delegate = self
imagePickerController.allowsEditing = true
present(imagePickerController, animated: true, completion: nil)
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
dismiss(animated: true, completion: nil)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// get the image
var selectedImageFromPicker: UIImage?
if let editedImage = info["UIImagePickerControllerEditedImage"] as? UIImage {
selectedImageFromPicker = editedImage
}else if let originalImage = info["UIImagePickerControllerOriginalImage"] as? UIImage {
selectedImageFromPicker = originalImage
}
if let selectedImage = selectedImageFromPicker {
//doSomethingWithTheImage(image: selectedImage)
}
dismiss(animated: true, completion: nil)
}
override func viewDidLoad() {
super.viewDidLoad()
collectionView?.backgroundColor = .black
collectionView?.register(HomeView.self, forCellWithReuseIdentifier: cellId)
}
override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 1
}
override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! HomeView
cell.delegate = self
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: view.frame.width, height: view.frame.height)
}
}
View
class HomeView: UICollectionViewCell {
// break retain cycle with weak var
weak var delegate: ImagePickerDelegate?
override init(frame: CGRect) {
super.init(frame: frame)
setupViews()
}
lazy var profileImageView: UIImageView = {
let iv = UIImageView()
iv.isUserInteractionEnabled = true
iv.image = UIImage(named: "kuang-si-falls-waterfall-water-laos-50588.jpg")
iv.contentMode = .scaleAspectFill
let tap = UITapGestureRecognizer(target: self, action: #selector(loadImagePicker))
iv.addGestureRecognizer(tap)
return iv
}()
func loadImagePicker() {
delegate?.loadImagePicker()
print(" imagePickerProtocol called ")
}
func setupViews() {
backgroundColor = .white
addSubview(profileImageView)
profileImageView.centerXAnchor.constraint(equalTo: self.centerXAnchor).isActive = true
profileImageView.centerYAnchor.constraint(equalTo: self.centerYAnchor).isActive = true
profileImageView.frame = CGRect(x: 0, y: 0, width: 150, height: 150)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}