code: protected void setGalleriesVisible(boolean visible) {
  
          if (visible) {
              m_noGalleriesLabel.getElement().getStyle().clearDisplay();
              m_galleryTree.getElement().getStyle().clearDisplay();
          } else {
              m_galleryTree.getElement().getStyle().setDisplay(Display.NONE);
              m_noGalleriesLabel.getElement().getStyle().setDisplay(Display.NONE);
  
          }
      }
docs: Shows or hides the tree for the gallery mode.<p>
  
  @param visible true if the tree should be shown