contribute_photo_dialog.dart

Future _getImage(BuildContext context) async {
  // Use the image_picker package to prompt the user for a photo from their
  // device.
  final File image = await ImagePicker.pickImage(
    source: ImageSource.camera,
  );

  // Store the image that was selected.
  setState(() {
    _image = image;
    _isUploading = true;
  });

  // Make a request to upload the image to Google Photos once it was selected.
  final String uploadToken =
      await ScopedModel.of<PhotosLibraryApiModel>(context)
          .uploadMediaItem(image);

  setState(() {
    // Once the upload process has completed, store the upload token.
    // This token is used together with the description to create the media
    // item later.
    _uploadToken = uploadToken;
    _isUploading = false;
  });
}