/**
  * @param action
  * @param showInstalledJob
  * @param event
  */
 private void updateContributedUI(
     final ShowContributedExtensionsJob showContributedJob, final IJobChangeEvent event) {
   if (event.getResult().isOK()) {
     // update exchange view
     List<ComponentExtension> extensions = showContributedJob.getfContributedExtensions();
     ExchangeManager.getInstance().updateContributedExtensions(extensions);
   }
 }
  /**
   * Update ui after job finished.
   *
   * @param action
   * @param job
   * @param event
   */
  private void updateUI(final RefreshJob job, final IJobChangeEvent event) {
    // activate action again after job finished

    if (event.getResult().isOK()) {
      // update exchange view
      List<ComponentExtension> extensions = job.getAvailableExtensions();
      ExchangeManager.getInstance().updateAvailableExtensions(extensions);
    }
  }