/**
   * Set the widget to display in content area.
   *
   * @param content the {@link Widget} to display
   */
  public void setWidget(IsWidget content) {
    contentContainer.setWidget(content);

    // Do not animate the first time we show a widget.
    if (firstContentWidget) {
      firstContentWidget = false;
      contentContainer.animate(0);
    }
  }