public interface someInterface() {
    void takePhoto(InputStream stream);
}
__________________________
public class IOSLauncher implements someInterface() {
...
...
@Override
    public void iosPickImage(final InputStream stream) {
        // Gallery
        MyDelegatePicker delegate = new MyDelegatePicker() {
            @Override
            public void didFinishPickingMedia(UIImagePickerController picker, UIImagePickerControllerEditingInfo info) {
                UIImage selectedImage = info.getOriginalImage();

                try {
                    stream.read(selectedImage.toPNGData().getBytes());

                } catch (IOException e) {
                    e.printStackTrace();
                }

                picker.dismissViewController(false, null);
            }

            @Override
            public void didCancel(UIImagePickerController picker) {
                picker.dismissViewController(false, null);
            }
        };
        UIViewController controller = ((IOSApplication) Gdx.app).getUIViewController();
        MyImagePickerController imagePicker = new MyImagePickerController();
        controller.addChildViewController(imagePicker);
        controller.getView().addSubview(imagePicker.getView());
        imagePicker.getView().setBounds(controller.getView().getBounds());
        imagePicker.setSourceType(UIImagePickerControllerSourceType.PhotoLibrary);
        imagePicker.setDelegate(delegate);
        imagePicker.addStrongRef((ObjCObject) delegate);
    }

public class EditScreen implements Screen {
someInterface interface;

 public EditScreen(MainClass gam ) {
        game = gam;
        this.interface = game.interface;
...
...

boxImage2.addListener(new ChangeListener() {
                @Override
                public void changed(ChangeEvent event, Actor actor) {
                    iosPickImage(???);
                }
            });

@Override
    public void iosPickImage(final InputStream stream) {
        try {
            StreamUtils.copyStream(stream, file.write(false));
        } catch (IOException e) {
            e.printStackTrace();
        }
        pending = executor.submit(new AsyncTask<Pixmap>() {
            @Override
            public Pixmap call() throws Exception {
                final byte[] bytes = file.readBytes();
                final Pixmap pix = new Pixmap(bytes, 0, bytes.length);
                return pix;
            }
        });

    }