ADD Column type link in UWL

Hello,

I want to add a column in UWL with fixed content (e.g ‘invoice image ') , the type of this column must be a link  and point to an action that launches a specific abap code.

I modified the UWL configuration file where I added the new column but it steel empty , I do not know how to fill it with the link (‘invoice image ') and how to point to an action.

Thank you for your help.