      /**
       * The constants used in this Content Widget.
       */
      public static interface CwConstants extends Constants,
          ContentWidget.CwConstants {
        String cwGridDescription();

        String cwGridName();
      }

      /**
       * An instance of the constants.
       */
      private CwConstants constants;

      /**
       * Initialize this example.
       */
      @Override
      public Widget onInitialize() {
        // Create a grid
        Grid grid = new Grid(4, 4);

        // Add images to the grid
        int numRows = grid.getRowCount();
        int numColumns = grid.getColumnCount();
        for (int row = 0; row < numRows; row++) {
          for (int col = 0; col < numColumns; col++) {
            grid.setWidget(row, col, Showcase.images.gwtLogo().createImage());
          }
        }

        // Return the panel
        grid.ensureDebugId("cwGrid");
        return grid;
      }