How to reach results of a function from another file (TextEditingController, ElevatedButton) - flutter

Question

I have two files, in the first are a few TextformFields and in the second are buttons. I wanna disable the button when one of the TextformFields is empty.
File 1:
class FormTextState extends State<FormText>{
final TextEditingController inputController1 = TextEditingController();
final TextEditingController inputController2 = TextEditingController();
final TextEditingController inputController3 = TextEditingController();
bool submit1 = false;
bool submit2 = false;
bool submit3 = false;
#override
void initState(){
super.initState();
inputController1.addListener(() { setState(() {
submit1 = inputController1.text.isNotEmpty;
});
});
inputController2.addListener(() { setState(() {
submit2 = inputController2.text.isNotEmpty;
});
});
inputController3.addListener(() { setState(() {
submit3 = inputController3.text.isNotEmpty;
});
});
}
#override
void dispose(){
inputController1.dispose();
inputController2.dispose();
inputController3.dispose();
super.dispose();
[...]
}
For each TextFormField the controller is defined as following:
TextFormField(
controller: inputController1,
If I would create the button directly in this file, everything works fine like that:
ElevatedButton(
onPressed: submit1 && submit2 && submit3 ? () => doSomething() : null,
How can I reach this result from the other file with the buttons? The submit values are not reachable. I imported the file at the beginning, of course.

Answer 1

You could add a function to your class like:
class FormTextState extends State<FormText>{
final Function(String str) stringHandler;
...
and when creating the class
FormTextState(stringHandler: _handler);
Future<void> _handler(String str) async {
print(str);
}

Answer 2

you nee to use the following porperties
autovalidateMode: AutovalidateMode.onUserInteraction
onChanged: (val) {
if (formKey.currentState?.validate() == true) {
BlocProvider.of<MyDataBloc>(context)
.add(ActivateButtonEvent());
} else {
BlocProvider.of<MyDataBloc>(context)
.add(DeActivateButtonEvent());
}
},
this will work for formtextfield in case that you are using bloc