# File rbSnack/tkSnackUtil.rb, line 426
   def refresh anew=false
     0.upto(@boxes.length-1) do |i|
       box=@boxes[i]
       color=box[2]
       w,  h = @canvas.width, @canvas.height
       @vLine[i]= @hLine[i]= @bkDot[i]=nil if anew
       @vLine[i]=TkcLine.new(@canvas,box[0],0,box[0],h){ fill color} if box[3]==true and @vLine[i]==nil
       @hLine[i]=TkcLine.new(@canvas,0,box[1],w,box[1]){ fill color} if box[4]==true and @hLine[i]==nil
       @bkDot[i]=TkcRectangle.new(@canvas,box[0]-5,box[1]+5,
                      box[0]+5,box[1]-5){ fill color} if @bkDot[i]==nil
       @onRefresh.call(i) if @onRefresh
     end
   end