IOS

Image picker (UIImagePickerController)

UIImagePickerController allows to pick image or video from photo library on device.

App must have the permission to access the photo library. So you need add following keys with description to the app info.plist.

  • NSCameraUsageDescription - allows to use camera
  • NSPhotoLibraryUsageDescription - allows to use photo library

There are three types of image source:

  • .camera
  • .photoLibrary
  • .savedPhotosAlbum

Use the key .editedImage in the picker delegate if imagePicker.allowsEditing is set to true, or .originalImage in otherwise.

image picker example 
class MyController: UIVIewController {

    private lazy var photoImageView: UIImageView = {
         let v = UIImageView()
         // v.contentMode = .scaleAspectFit
         v.layer.cornerRadius = 4
         return v
    }()
    
    func selectImage() {
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.allowsEditing = true
        imagePicker.mediaTypes = ["public.image", "public.movie"]
        imagePicker.sourceType = .camera
        present(imagePicker, animated: true) {
            print("imagePicker presented")
        }
    }
    
    func setupLayout {
        // ...
    }
// ...
}

// MARK: - UIImagePickerControllerDelegate
extension MyController: UIImagePickerControllerDelegate {
    
    func imagePickerController(
        _ picker: UIImagePickerController,
        didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any])     { 
        guard let image = info[.editedImage] as? UIImage else { return }
        photoImageView.image = image
        
        for constrain in photoImageView.constraints where
            constrain.identifier == "photoImageViewHeight"
        { constrain.constant = 158 }
        photoImageView.layoutIfNeeded()
        picker.dismiss(animated: true, completion: nil)
    }
    
    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        picker.dismiss(animated: true, completion: nil)
    }
}