AJAX Dynamic Select List

Question

Hello Ladies and Gentlemen,
I have a Select List, :P9_ELEMSTRUCTSAISIEPARCBO, based on a hidden item, :P9_NOSAISIEPAR, and this is the query it's based upon:
select Description, ElemStructID
from V_ElemStruct, V_Dispensateur
where DispensateurID = DispensateurIDResponsable
and NumeroDispensateur = :P9_NOSAISIEPAR
order by DescriptionI also have a popup page that shows a report with a column link that passes back values to the original page, and one of those values replace :P9_NOSAISIEPAR's current value. I want to reload the Select List via AJAX, so that the changes can be in real-time. I found Carl Backstrom's (He was a wonderful man) tutorial on his application (http://apex.oracle.com/pls/otn/f?p=11933:37) and decided to try it. But it just won't work, and I have no idea why.
I know the popup works just fine, and I tested the On Demand Application Process in the SQL Commands of the SQL Workshop and it seems to be working just as fine. Thus, I've narrowed it down to the thought that the JavaScript must be the problem, logically.
Here is the code for the "HTML Form Element Attributes" of the :P9_NOSAISIEPAR hidden item:
onChange="f_PopulateField(this,'P9_ELEMSTRUCTSAISIEPARCBO')"Here's my on Demand Application Process:
begin
  owa_util.mime_header('text/xml', FALSE);
  htp.p('Cache-Control: no-cache');
  htp.p('Pragma: no-cache');
  owa_util.http_header_close;
  htp.prn('<select>');
  for rec in
  (select
     Description as Description,
     ElemStructID as ElemStructID
   from
     V_ElemStruct,
     V_Dispensateur
   where
     DispensateurID = DispensateurIDResponsable
     and NumeroDispensateur = :F102_TEMP_APP_ITEM
   order by
     Description
  ) loop
  htp.prn('<option value="' || rec.ElemStructID || '">' || rec.Description || '</option>');
  end loop;
  htp.prn('</select>');
end;and here's my JavaScript:
function f_PopulateField(pThis,pSelect)
  var l_Select = $x(pSelect);
  var l_Return = null;
  var get = new htmldb_Get(null,$x('pFlowId').value,'APPLICATION_PROCESS=PopulateField',0);
  get.add('F102_TEMP_APP_ITEM',pThis.value)
  gReturn = get.get('XML');
  if(gReturn && l_Select)
    var l_Count = gReturn.getElementsByTagName("option").length;
    l_Select.length = 0;
    for(var i=0;i<l_Count;i++)
      var l_Opt_Xml = gReturn.getElementsByTagName("option");
appendToSelect(l_Select, l_Opt_Xml.getAttribute('value'),l_Opt_Xml.firstChild.nodeValue)
get = null;
function appendToSelect(pSelect,pValue,pContent)
var l_Opt = document.createElement("option");
l_Opt.value = pValue;
if(document.all)
pSelect.options.add(l_Opt);
l_Opt.innerText = pContent;
else
l_Opt.appendChild(document.createTextNode(pContent));
pSelect.appendChild(l_Opt);
I have installed FireFox and FireBug, and I tried to debug my JavaScript, and that made me realize something. In the FireBug's HTML tab, :P9_NOSAISIEPAR doesn't have any onChange events mapped to it (and all my other items which should have an event mapped to them do have one).
<input type="hidden" id="P9_NOSAISIEPAR" value="2222" name="p_t63">compared to:
<select onchange="$f_Show_On_Value_Item('P9_SECURITAIRE','P9_NOTEACCOMPAGNATEUR',1)" id="P9_SECURITAIRE" size="1" name="p_t23">So, my best bet is that the JavaScript doesn't even get executed by the page at all (it's not appearing in FireBug's JavaScript tab at all either). Any idea why?
Best regards,
Mathieu

Answer 1

I finally found a way to do it. When selecting my value in my popup page, I show my hidden field, change the value, manually call the onChange event, hide back my hidden field, and then close the popup. That way the onChange event fires in IE. Afterwards, as a workaround to the XML not being recognized by IE, I changed
get.get('XML')for
get.get()to get a string instead of some XML, and I parsed it to XML DOM using a manual parser (because IE is too weak to have its own). Here is the code for the DOMParser.
if (typeof DOMParser == "undefined")
    DOMParser = function () {}
    DOMParser.prototype.parseFromString = function (str, contentType)
      if (typeof ActiveXObject != "undefined")
        var d = new ActiveXObject("MSXML.DomDocument");
        d.loadXML(str);
        return d;
      else if (typeof XMLHttpRequest != "undefined")
        var req = new XMLHttpRequest;
        req.open("GET", "data:" + (contentType || "application/xml") +
                         ";charset=utf-8," + encodeURIComponent(str), false);
        if (req.overrideMimeType)
          req.overrideMimeType(contentType);
        req.send(null);
        return req.responseXML;
  }It wasn't written by me, I found it on Erik's Weblog (http://erik.eae.net/archives/2005/07/03/20.19.18/), so all credit goes to him.
Best regards,
Mathieu