public boolean showLoading() {
    if (pageBook.isDisposed()) {
      return false;
    }
    Display display = getDisplay();
    display.syncExec(
        new Runnable() {

          @Override
          public void run() {
            pageBook.showPage(loadingComposite);
            setBusyIndicator(loadingComposite, true);
            form.reflow(true);
            form.redraw();
          }
        });
    return true;
  }
  public boolean refresh() {
    if (pageBook == null
        || pageBook.isDisposed()
        || discoveryViewer == null
        || discoveryViewer.getControl() == null) {
      return false;
    }
    Display display = getDisplay();
    display.syncExec(
        new Runnable() {

          @Override
          public void run() {
            pageBook.showPage(discoveryViewer.getControl());
            form.reflow(true);
            form.redraw();
          }
        });

    return true;
  }
 /*
  * (non-Javadoc)
  *
  * @see org.eclipse.ui.part.IPage#dispose()
  */
 public void dispose() {
   if (fPageBook != null && !fPageBook.isDisposed()) fPageBook.dispose();
   fPageBook = null;
   fDisposed = true;
 }