jqGrid: Sending param with dataUrl - ruby-on-rails

Question

I'm trying to create a dependent dropdown box. 'element' is dependent on 'grouping'.
My ajaxSelectOptions function seems to work, as 'temp' is passed, but then it isn't used by 'populate_element'. How can I use the 'temp' as my parameter :id?
My grid:
jQuery(document).ready(function(){
var lastsel;
var grid = jQuery("#list").jqGrid({
url:'codes/get_data.xml',
datatype: 'xml',
mtype: 'GET',
colNames:['ID', 'Version', 'Grouping', 'Element', 'Name'],
colModel:[
{name: 'id', index: 'id', hidden: true, editable: false },
{name: 'version', index: 'version',editable: true, editrules:{number:true}, cellEdit: true, search:true },
{name: 'grouping', index: 'grouping', editable: true, edittype: 'select', editoptions: {dataUrl: 'codes/populate_grouping.html'} },
{name: 'element', index: 'element', editable: true, edittype: 'select' }
],
pager: '#pager',
rowNum:200,
rowList:[50,100,200],
sortname: 'id',
sortorder: 'asc',
viewrecords: true,
height: 500,
scrollrows: true,
rownumbers: false,
caption: 'GL Codes',
editurl: 'codes/post_data.xml',
onSelectRow: function(id){
$("#list").setColProp('element', {editoptions: { dataUrl: 'codes/populate_element.html' }});
if(id && id!==lastsel){
$('#list').restoreRow(lastsel);
lastsel=id;
}
$('#list').editRow(id,true);
},
ajaxSelectOptions: {
data: {
temp: function(temp){
return grid.jqGrid('getGridParam', 'selrow')
}
}
}
});
Here is my error message:
Started GET "/codes/populate_element.html?temp=4" for 127.0.0.1 at 2012-09-27 17:18:33 +1200
Processing by CodesController#populate_element as HTML
Parameters: {"temp"=>"4"}
Completed 500 Internal Server Error in 1ms
ActiveRecord::RecordNotFound (Couldn't find Code without an ID):
app/controllers/codes_controller.rb:73:in `populate_element'
Update
I established that it was actually just a ruby syntax error in calling the param, rather than a jqGrid problem. For reference, I ended up calling it like so ... #code = Code.where(["id = ?",params[:temp]]).first

Answer 1

I think the problem is that you use wrong ids for the rows of grid. The error exist during filling of the grid. The most easy way to fix the problem will be to add key: true property to the definition of the 'id' column in colModel. In the case the value from the column id will be used as the rowid: the value of id attribute of rows (<tr>) of the grid.