DFT stroke: test
Add the listener in global:
function newStrokeListener(obj) {
  for (ind =  ggbApplet.getObjectNumber()-1; ind>=0;  ind=ind-1){
   nam= ggbApplet.getObjectName(ind);
   typ= ggbApplet.getObjectType(nam);
   /*alert(""+ind+"  "+nam+"  "+typ)*/
     if (typ == "penstroke") {
        ggbApplet.evalCommand("SetValue(userdraw, true)");
     }
  }
}
Note: The result of the online version differs drastically compare to the offline version. Download to see the difference.