Displaying selected image on screen using UIIamgePickerControllerDelegate in Swift - ios

Question

I am attempting to learn more about the delegate pattern. I have written an app that accesses the user's camera roll and I want to display that image on the view controller after the user selects the image. Here is what I have thus far:
import UIKit
class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
#IBOutlet weak var imagePickerView: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
// Delegate Methods
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if let image = info[UIImagePickerControllerOriginalImage] as? UIImage {
imagePickerView.image = image
}
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
self.dismiss(animated: true, completion: nil)
}
#IBAction func pickAnImage(_ sender: Any) {
let pickerController = UIImagePickerController()
present(pickerController, animated: true, completion: nil)
}
}
The camera roll appears as expected and the Cancel buttons dismiss the modal. Selecting an image also dismisses the modal, however that image is not displayed on the screen. I have confirmed that my imagePickerController is corrected referenced as an outlet. What am I missing?

Answer 1

You have to dismiss the controller once the image is selected, maybe the following detailed function will help you.
For Swift 4.2:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
var selectedImageFromPicker: UIImage?
if let editedImage = info[.editedImage] as? UIImage {
selectedImageFromPicker = editedImage
} else if let originalImage = info[.originalImage] as? UIImage {
selectedImageFromPicker = originalImage
}
if let selectedImage = selectedImageFromPicker {
imageView.image = selectedImage
}
dismiss(animated: true, completion: nil)
}
Before Swift 4.2:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
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 {
imageView.image = selectedImage
}
dismiss(animated: true, completion: nil)
}
Since I've received many points from this answer I'm adding a more concise answer (Just one line is required for setting the image to imageView).
Bonus Answer:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
imageView.image = (info[.editedImage] ?? info[.originalImage]) as? UIImage
dismiss(animated: true)
}

Answer 2

You need to set the view controller as the delegate of pickerController
// pickerController.delegate = self
Also check the imagePickerView outlet is connected.

Answer 3

Ensure you have made all inclusions in the info.plist file
Ensure you have all the delegates set
Ensure what you are using to display image (e.g if editing is set to true, then UIImagePickerControllerEditedImage else UIImagePickerControllerOriginalImage)