Dynamically display message from workflow action handler

[aliism]

Firstly, I want to thank jllort and pavila for their huge help!

Here is my problem: In one task user uploads a file. In action handler I check if file is valid. If it's not valid I restart the task. How can I notify the user why the task was restarted?

[jllort]

From UI will not be trivial, the easies way from UI should be come back to previous task and add some comment ( you can add comments on workflow ), but could not be seeing by the user. Other solution could be send some mail. And for me the best solution could be go to some task only for display information, and continue go back to initial task.

Your problem indicate to me that should be necessary some warning or message form element - which actually we have not - I will think on it. Now you could use GWTText and GWTSeparator. Really I think GWTText could have some additional property like status="info, warning, error" and then colorate or something more easy like color="red" to make it more visible to end user.