sclass StackLayouter extends F1<Container, Dimension> {

  Map<Component, Int> heights = weakHashMap();

  int gap = 5;

  //int defaultHeight = 50;

  int preferredWidth = 300;

  bool maximizeIfSingleComponent = true;

  Dimension get(Container parent) {

    L<Component> l = getComponents(parent);

    Insets insets = unnullInsets(parent.getInsets());

    Dimension size = parent.getSize();

    ifdef StackLayouter_debug

      print("StackLayouter: n=" + l(l) + ", insets=" + insets + ", size=" + size);

    endifdef

    int y = insets.top;

    int width = size.width-insets.left-insets.right;

    for (Component c : l) {

      Int H;

      if (maximizeIfSingleComponent && l(l) == 1) {

        ifdef StackLayouter_debug

          print("StackLayouter maximizing!");

        endifdef

        H = size.height-insets.bottom-y;

      } else

        H = heights.get(c);

      int h = H != null ? H : c.getPreferredSize().height;

      c.setBounds(insets.left, y, width, h);

      y += h+gap;

      ifdef StackLayouter_debug

        print("StackLayouter: y=" + y + ", h=" + h);

      endifdef

    }

    // return preferred size (hm.)

    ret new Dimension(preferredWidth, max(50 /* XXX */, y+insets.bottom-gap));

  };

}