code: private void addRow(Dimension dim, int rowWidth, int rowHeight)
  	{
  		dim.width = Math.max(dim.width, rowWidth);
  
  		if (dim.height > 0)
  		{
  			dim.height += getVgap();
  		}
  
  		dim.height += rowHeight;
  	}
docs: /*
  A new row has been completed. Use the dimensions of this row
  to update the preferred size for the container.
  
  @param dim update the width and height when appropriate
  @param rowWidth the width of the row to add
  @param rowHeight the height of the row to add