I am developing a simple activiti project with activiti-cdi+jsf. I have a situation that when assignee start the task from his mail box page and gets update screen and he has to fill additional data. What if the update screen contains links to additional data screens. How to manage the data on the additional screens and go back to the update screen so that he can submit the whole data and redirect to mailbox page. Sorry for my bad English..
That is something related to the UI-technology you're using, not activiti-related… You'll need to store unsubmitted data in some kind of session, that you access from both screens. When submitting, the session-data can be passed to the Activiti API, but that's java 101.
I'm not sure if I'm following you. But the data gathering should be of no concern of Activiti. Activiti only cares about it until you submit the form. Unless ou model the data gathering as separate steps.