Do all text fields need to be on stage or in library?

When creating Flash templates, do the movie clips containing text fields that will be populated, need to be either on the stage or in the library for the Flash/Animate Template Generator to see them?

As an AS developer I no longer use the timeline/stage and create all my objects through ActionScript so I would create a textfield something like this:

var textField:TextField = new TextField(); = "textfield_1";

Would the Caspar SetData() function be able to see this text field and then populate it?