hi all, i created a sub-process as quick task for process record.

Hi Eagle, if you are calling this as a subprocess, then check that the node with the subprocess call is assigned to Run as whoever designed this process model. Otherwise you could be seeing the form for the subprocess call step.

hi Ray, but if a sub-process is configured as a quick task, the node(run as whoever designed) is disabled, please see the attached pic

Thanks Eagle, I see your problem.
Rather than define this as a quick task in the process model, you'll need to set it up to call directly from the Record, in the Related Actions section. You can pass the process id in the context field e.g., {requestId: rp!id} , where pv!requestId is the field in the subprocess

in this case, how can i update the process variables in parent process,
i know there are two types of related action

Here's a screenshot of a similar example. It's the subprocess call which is causing the form to appear from what you describe, so this should remove that problem. This also allows you to use it as a button on the form (assuming) you're on 7.7 or later.

hi Ray, my purpose is to update the process variables through related actions,
if use independent model as related action, is it possible to update the variables in the parent process?

You can use a Send Message event to push any data back up. Use a receive message on the calling process to pick it up.

yes, i forgot that. thank you very much, Ray.
theoretically, sub-process should be able to be configured as a quick task.
don't know why it doesn't work. "start form" alwasy shows....

True. It's because it's a quick task, this means Appian is trying to start the subprocess as a user, and therefore wants input into it.

Hi Eagle,
1. Though we can target specific process using send and receive message node, But messaging is not synchronous.If your parent process don't have any logic which require immediate modification of pv after execution of related action then you can prefer the messaging.
2. You can use 'Set external pv' smart service to modify the process variable in another process(Process variable updated by this smart service wont get logged in process history)