private void createMigLayoutGrid() {
    // System.out.println("createMigLayoutGrid");
    this.grid =
        new Grid(fx2ContainerWrapper, lc, rowSpecs, colSpecs, fx2ComponentWrapperToCCMap, null);
    this.valid = true;

    // -----------------------------------------
    // set MigLayout's own size
    setMinWidth(LayoutUtil.getSizeSafe(grid.getWidth(), LayoutUtil.MIN));
    setPrefWidth(LayoutUtil.getSizeSafe(grid.getWidth(), LayoutUtil.PREF));
    setMaxWidth(LayoutUtil.getSizeSafe(grid.getWidth(), LayoutUtil.MAX));

    setMinHeight(LayoutUtil.getSizeSafe(grid.getHeight(), LayoutUtil.MIN));
    setPrefHeight(LayoutUtil.getSizeSafe(grid.getHeight(), LayoutUtil.PREF));
    setMaxHeight(LayoutUtil.getSizeSafe(grid.getHeight(), LayoutUtil.MAX));
    // -----------------------------------------
  }
 @Override
 protected double computePrefWidth(double height) {
   int w = LayoutUtil.getSizeSafe(grid != null ? grid.getWidth() : null, LayoutUtil.PREF);
   return w;
 }
 @Override
 protected double computePrefHeight(double width) {
   int h = LayoutUtil.getSizeSafe(grid != null ? grid.getHeight() : null, LayoutUtil.PREF);
   return h;
 }