Set current post ID in widget

How can I get the current post ID in the PODS single value widget?
The fields of the widget are:
Title _____
Pod _____
Slug or ID _____
Field _____
Title ok (I can leave it blank).
Pod is the name of the Pod, that’s ok.
Field is the field I want to display in the widget, ok.
But how can I tell the widget to get the slug or ID of the current post?
I want it to be the field of the current post.