How to make users fill in field after changing task status

[appsmobiliojivisata]

Hello!

I want to make my users fill in Resolution field when task goes to Done status. How can i do it? I can't find post-function or validation function to make it

[Jack Brickey · Accepted solution]

You can add a validator to the workflow transition. So if you want someone to fill in the field whenever an issue is moved to done you would add a validator to any transition into the done status. Pick the field that you want the validator to require and add an error message if you choose as well. Note that this is associated with company manage projects or classic projects not team managed projects. 

[Trudy Claspill]

Adding to @Jack Brickey 's reply, the Validator option you want is "Field Required Validator"