var intent = new android.content.Intent(android.content.Intent.ACTION_GET_CONTENT);
  intent.setType("image/*");

  app.startActivityForResult(intent, (resultCode, data) => {
      toastLog('intent3')
      if (resultCode === android.app.Activity.RESULT_OK) {
          var uri = data.getData();
          callback.onReceiveValue(uri ? [uri] : null);
      } else {
          callback.onReceiveValue(null);
      }
  });