visual studio lightswitch - Set related entity to current user in HTML Client -

i building desk ticketing program in lightswitch, , have been having trouble 1 requested feature. asked build mobile friendly version of app end users submit tickets mobile devices. built app, couple screens, , added code preprocess query limit tickets can see own. works wonderfully. i'm having trouble assigning logged in user submitter on new ticket. i've looked @ multiple guides online, of stop short @ i'm trying do. promising i've found http://social.msdn.microsoft.com/forums/vstudio/en-us/47832659-4ed3-4a8c-9a62-b3ad46c8e8b4/get-logged-in-employee technique, can succesfully display current user on screen.

the challenge is, setting ticket.enduser field currentusername field. i've tried in created method of addeditnewticket screen, , beforeapplychanges method.

i've been bashing head against wall couple days now, has out there ever accomplished this?

---

update

so, think may have found problem, not sure how around it. in execute code new ticket button, create ticket, , use newticket.setenduser(). function takes enduser entity parameter, retrieve myapp.activedataworkspace.mydatabase.techs_singleordefault(currentusername) returns null. username primary key techs table.

even when use literal string username, still returns null.

found it!

this forum post had answer. http://social.msdn.microsoft.com/forums/vstudio/en-us/dffe99ea-f12f-42e4-be14-7d5d04c2621f/entitytype-dataworkspaceapplicationdatatypessingleordefaultpr-in-javascript

i had wrap call tech or end user in promise object, gave me array tech/end user looking for, had first element of array.

myapp.activedataworkspace.mydatabase.techs_singleordefault(currentusername).execute().then(function (result) {  entity.settech(result.results[0]); }); 

hopefully save frustration trying in future.