Padding from a Variable

I want to set the padding based on a value in one of my documents. I have put this value (a double) in a text box to see if it is being read correctly. It is. It appears the padding may be looking for a double, but I've tried an int and dbl. When I build a test session it fails and gives the following error:

Launching lib/main.dart on Web Server in debug mode...

Waiting for connection from debug service on Web Server...

lib/pages/testpage/testpage_widget.dart:81:27: Error: The getter 'textTestBlrsRunningRecord' isn't defined for the class '_TestpageWidgetState'.

- '_TestpageWidgetState' is from 'package:boiler_test/pages/testpage/testpage_widget.dart' ('lib/pages/testpage/testpage_widget.dart').

Try correcting the name to the name of an existing getter, or defining a getter or field named 'textTestBlrsRunningRecord'.

textTestBlrsRunningRecord?.value2,

^^^^^^^^^^^^^^^^^^^^^^^^^

Waiting for connection from debug service on Web Server... 46.6s

Failed to compile application.

I've reviewed the docs. Can anyone provide me more information on how to do this?

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