No I do not believe what you are exactly requesting is a feature currently in the product. I do know that some specific events can be conditionalized with when conditions. And OpenAssignment appears to be one of them. Maybe you can explore this approach to achieve your requirements.
We raised a Pega SR B-70004 regarding the same issue.
When Condition on click of button not working.
When Condition on click of button not working
We have a button on modal window on click of which we are setting a error flag and if errorflag is true then we are running next action(open assignment).
Issue : Irrespective of the value of error flag, Open assignment is always running.
Steps to Reproduce
1) Configure a modal window with comment box.
2) Configure button on modal window, On click event of button, apply 2 actions 1) Run Activity 2) Open Assignment
3) If comment box is blank on modal window, then set error flag in activity and exit activity.
4) If Error flag is true, then skip open assignment action(Apply when rule or property condition)
5) If comment box is not blank then Run activity and Open Assignment.
Issue : Open assignment is always running irrespective of the value of errorflag.
Tried to save errorflag on primary page, pyworkpage and systemlevel pages but this is not working in any scenario.
Below are the comments from Pega :
The scenario that your have provided and the issue that you describe is a known issue. Some customers have already reported this in the past. The short answer for it is that unfortunately this is not a supported configuration. Please refer to this PDN article that talks about it.
Actually the documentation about this When Conditions is poor and does not clearly state the limitations. We already have an internal bug to update the documentation in our product for a future release.