There are two types of conflicts detected by LCDS - those detected on
the server when you try to update with stale data, and those detected on
the client when you have uncommitted changes to an item which receives a
pushed change.
For the server detected conflicts, it is up to the assembler to
determine when a conflict has occurred for a given update. Some
assemblers like the hibernate assembler have an option you can set to
choose "object" versus "property" level detection. An object level
conflict detection would trigger a conflict if any change had been made
to that object since the client fetched its version. A property level
conflict is generated only when the property changed by the client has
been changed on the server. Check the source for the hibernate
assembler if you are interested in more details on how to implement that
on the server.
For the client detected conflicts, unfortunately right now we only
implement "property" level conflict detection out of the box. You can
supply your own "ConflictDetector" implementation though by setting the
DataService.conflictDetector property to an instance of a class you
write which extends ConflictDetector. When your checkUpdate method is
called, you can signal a conflict whenever there is a local change to
the item being updated on the server.
You would extend conflictDetectory and override your checkUpdate method
something like this:
override public function checkUpdate(remoteChange:IChangeObject,
localChange:IChangeObject):void
{
var changes:Array = remoteChange.changedPropertyNames;
var conflictingProps:Array = null;
if (localChange != null)
{
var currentVersion:Object = localChange.currentVersion;
if (localChange.isUpdate())
{
remoteChange.conflict("Local item has changes to
properties that conflict with remote change.", changes);
}
}
super.checkUpdate(remoteChange, localChange);
}
Jeff
________________________________
From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On
Behalf Of Maciek Sakrejda
Sent: Tuesday, April 29, 2008 8:24 AM
To: flexcoders@yahoogroups.com
Subject: Re: [flexcoders] How to choose data generating conflict
withLiveCycle Data Services ?
Well, the immediate thing that comes to mind is track a hash of "first
name + last name", and update this if either changes. Not the cleanest
solution, but it should solve your problem (assuming you have control
over the schema of the persisted employee objects).
--
Maciek Sakrejda
Truviso, Inc.
http://www.truviso.com <http://www.truviso.com>
-----Original Message-----
From: Mathieu Fernandez <[EMAIL PROTECTED]
<mailto:mathieu.fernandez%40keepcore.com> >
Reply-To: flexcoders@yahoogroups.com
<mailto:flexcoders%40yahoogroups.com>
To: flexcoders@yahoogroups.com <mailto:flexcoders%40yahoogroups.com>
Subject: [flexcoders] How to choose data generating conflict with
LiveCycle Data Services ?
Date: Tue, 29 Apr 2008 09:41:41 +0200
Hi everybody,
I made a little prototype handling conflicts with LCDS. I've got a web
AIR application which contains a grid (each line represents an
employee)
with 3 columns (ID, firstname, lastname) and a frrame on the top right
which contains the firstname and the lastname of the line selected (we
can modify those name and save).
When I modify the same data on 2 differents browser for example, I've
got a data conflict and I display a screen allowing the user to choose
between the server version and the client version (a litle bit like
this
video :
http://blog.phiphou.com/index.php/?2008/01/25/107-livecycle-data-service
s-gestion-de-conflits
<http://blog.phiphou.com/index.php/?2008/01/25/107-livecycle-data-servic
es-gestion-de-conflits> ).
The problem : In a line of my datagrid I've got an employee, his
firstname is "Lionel" and his lastname is "Messi". A conflict is
generated when I modify the same data at the time in 2 browser (for
example I modify the lastname in the 2 browser). I would like LCDS
generates a conflict when I modify the firstname in a browser and the
lastname in another browser at the same time (for the moment, when I do
this, the 2 operations succeed and the lastname and the firstname are
changed whereas I would like to generate a conflict).
How can I do ? I tried manyu things but I can't find an answer.
Thanks for all.
