Show alert in manager?

Hi all,

I’m working on a plugin which will notify the user upon save about that there is no TV-value set when creating a new resource.
I am stuck on how to display an alert in the manager.
The second step would be stopping the save, but that wouldn’t be the main priority, just a notification would do for now.

Any help would be appreciated.

Ahh i got the solution. Seems I wasn’t the only one with this problem.
Solution is to be found in this thread: http://modxcms.com/forums/index.php/topic,53865.0.html

Now I only need to find out how to access the template variables...