@Override
 public void onDownloadFinished(boolean success, File file) {
   if (downloadDialog.isShowing()) downloadDialog.cancel();
   if (success) {
     downloadDialog = new BaseDialog(this).getDownloadFinishedDialog(true, file.getAbsolutePath());
   } else {
     downloadDialog = new BaseDialog(this).getDownloadFinishedDialog(false, null);
   }
   downloadDialog.show();
 }
 private void stopLoading() {
   if (mLoadingDialog != null) {
     mLoadingDialog.cancel();
   }
   mLoadingDialog = null;
 }