How do I pass the result of a custom function to an AppState through text widget?

I am having the result of my queries on a "text field" on "text fields" and it's working fine, but when I tried to run a function I only got the result into a "text" widget (not the text field).

The problem is that I can update my App State values using the "text field" query results, but not using the "text field" which contains a function result, but in the only part where I can see the result of a function is the "text" Widget which but doesn´t allow me to pick the widget state to update the App State.