How to allow user to pick the image with Swift?

Question

I am writing my first iOS application (iPhone only) with Swift. The main application view should allow user to choose the image from the photo gallery.

I've found the following sample code of ViewController.swift:

class ViewController: UIImagePickerController, UINavigationControllerDelegate, UIImagePickerControllerDelegate  {      override func viewDidLoad() {         super.viewDidLoad()         // 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.     }      func tableView(tableView: UITableView!, didSelectRowAtIndexPath indexPath: NSIndexPath!) {          var imagePickerController = UIImagePickerController()         imagePickerController.delegate = self         imagePickerController.sourceType = UIImagePickerControllerSourceType.SavedPhotosAlbum         imagePickerController.allowsEditing = true         self.presentViewController(imagePickerController, animated: true, completion: { imageP in          })     }       func imagePickerController(picker: UIImagePickerController!, didFinishPickingImage image: UIImage!, editingInfo: NSDictionary!) {         let selectedImage : UIImage = image         println(selectedImage)     }  } 

and have the following View Controller Scene -

View Controller  - Top Layout Guide  - Bottom Layout Guide  - View    - Image View First Responder Exit 

But when I start the app, just black screen is shown. What I am doing wrong? Another sample code I've found is in Objective-C, which doesn't help me.

Answer 1

If you just want let the user choose image with UIImagePickerController use this code:

import UIKit   class ViewController: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate {      @IBOutlet var imageView: UIImageView!     @IBOutlet var chooseBuuton: UIButton!     var imagePicker = UIImagePickerController()      @IBAction func btnClicked() {          if UIImagePickerController.isSourceTypeAvailable(.savedPhotosAlbum){             print("Button capture")              imagePicker.delegate = self             imagePicker.sourceType = .savedPhotosAlbum             imagePicker.allowsEditing = false              present(imagePicker, animated: true, completion: nil)         }     }      func imagePickerController(picker: UIImagePickerController!, didFinishPickingImage image: UIImage!, editingInfo: NSDictionary!){         self.dismiss(animated: true, completion: { () -> Void in          })          imageView.image = image     } } 

Answer 2

Complete copy-paste working image picker for swift 4 based on @user3182143 answer:

import Foundation import UIKit   class ImagePickerManager: NSObject, UIImagePickerControllerDelegate, UINavigationControllerDelegate {      var picker = UIImagePickerController();     var alert = UIAlertController(title: "Choose Image", message: nil, preferredStyle: .actionSheet)     var viewController: UIViewController?     var pickImageCallback : ((UIImage) -> ())?;          override init(){         super.init()         let cameraAction = UIAlertAction(title: "Camera", style: .default){             UIAlertAction in             self.openCamera()         }         let galleryAction = UIAlertAction(title: "Gallery", style: .default){             UIAlertAction in             self.openGallery()         }         let cancelAction = UIAlertAction(title: "Cancel", style: .cancel){             UIAlertAction in         }          // Add the actions         picker.delegate = self         alert.addAction(cameraAction)         alert.addAction(galleryAction)         alert.addAction(cancelAction)     }      func pickImage(_ viewController: UIViewController, _ callback: @escaping ((UIImage) -> ())) {         pickImageCallback = callback;         self.viewController = viewController;          alert.popoverPresentationController?.sourceView = self.viewController!.view          viewController.present(alert, animated: true, completion: nil)     }     func openCamera(){         alert.dismiss(animated: true, completion: nil)         if(UIImagePickerController .isSourceTypeAvailable(.camera)){             picker.sourceType = .camera             self.viewController!.present(picker, animated: true, completion: nil)         } else {             let alertController: UIAlertController = {                 let controller = UIAlertController(title: "Warning", message: "You don't have camera", preferredStyle: .alert)                 let action = UIAlertAction(title: "OK", style: .default)                 controller.addAction(action)                 return controller             }()             viewController?.present(alertController, animated: true)         }     }     func openGallery(){         alert.dismiss(animated: true, completion: nil)         picker.sourceType = .photoLibrary         self.viewController!.present(picker, animated: true, completion: nil)     }           func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {         picker.dismiss(animated: true, completion: nil)     }     //for swift below 4.2     //func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {     //    picker.dismiss(animated: true, completion: nil)     //    let image = info[UIImagePickerControllerOriginalImage] as! UIImage     //    pickImageCallback?(image)     //}          // For Swift 4.2+     func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {         picker.dismiss(animated: true, completion: nil)         guard let image = info[.originalImage] as? UIImage else {             fatalError("Expected a dictionary containing an image, but was provided the following: \(info)")         }         pickImageCallback?(image)     }        @objc func imagePickerController(_ picker: UIImagePickerController, pickedImage: UIImage?) {     }  } 

Call it from your viewcontroller like this:

    ImagePickerManager().pickImage(self){ image in         //here is the image     } 

Also don't forget to include the following keys in your info.plist:

<key>NSCameraUsageDescription</key> <string>This app requires access to the camera.</string> <key>NSPhotoLibraryUsageDescription</key> <string>This app requires access to the photo library.</string>