logging text from server to client

rtext2.erl

%% -*- mode: nitrogen -*-
-module (rtext2).
-compile(export_all).
-include_lib("nitrogen_core/include/wf.hrl").
-include_lib("nitrogen_core/include/google_chart.hrl").
-include("records.hrl").

main() -> #template { file="./site/templates/raphael.html" }.

title() -> "Todd's <b>Raphael Text Log</b> Page".

body() -> 

  Panel = #panel { style="margin: 50px 100px;", body=[
      #span { text="Raphael Log Test Below" },
      #panel { id=holder, body=[ 
          #p { id=logtext, text="-"}
          %%#hidden { id=hiddentext }
      ]},
      #textbox { id=transfer, text="initial text", show_if=true }
    ]},
  wf:wire(transfer, #event { type=onchange, actions=#script { script="
        setRText(obj('transfer').text);
        "}}),
  wf:comet(fun() -> bg_update(transfer, 1, 5000) end),
  wf:wire(#script { script="
      var setRText=function(text){
        console.log('setting text');
        var hldr = obj('holder');
        var R = Raphael(hldr, 640, 480);
        var attr = {font: '50px Helvetica, Arial', opacity: 0.5};
        txt[0] = R.text(320, 240, text).attr(attr).attr({fill: 'hsb(0, .5, 1)'});
      };" }),
  Panel.

event(_) -> ok.

bg_update(ControlID, Count, Delay) ->
  timer:sleep(Delay),
  wf:update(ControlID, wf:to_list(Count)),
  wf:flush(),
  %%?PRINT(wf:wf("count=" ++ Count)),
  bg_update(ControlID, Count + 1, Delay).