Circular progress indicator not showing in flutter - flutter

Question

I am trying to show an CircularProgressIndicator whenever user presses on register button, here is my code:
onPressed: () async{
if (_email.isNotEmpty && _password.isNotEmpty) {
startProgressIndicator();
FirebaseAuth mAuth = FirebaseAuth.instance;
UserCredential credential = await mAuth.createUserWithEmailAndPassword(email: _email, password: _password);
print(credential.user!.email);
//stopProgressIndicator();
} else {
ScaffoldMessenger.of(context).showSnackBar(SnackBar(
content: Text(
"Please enter all information!",
style: TextStyle(
color: Colors.white,
fontSize: 15,
fontWeight: FontWeight.bold
),
),
backgroundColor: Colors.black,
elevation: 5,
duration: Duration(
seconds: 3
),
action: SnackBarAction(
label: "close",
onPressed: (){
ScaffoldMessenger.of(context).hideCurrentSnackBar();
},
),
));
}
startProgressIndicator():
CircularProgressIndicator startProgressIndicator() {
return CircularProgressIndicator(
valueColor: AlwaysStoppedAnimation<Color>(Colors.orange),
backgroundColor: Colors.black,
strokeWidth: 5,
);
}
stopProgressIndicator():
CircularProgressIndicator stopProgressIndicator() {
return CircularProgressIndicator(
value: 0,
);
}
The loading icon doesn't appear at all.
All colors are correct(i.e. background color and progress bar color are different)
What is the issue here?
EDIT: I added the following code but it still isn't working:
Column(
children: [
<Other widgets>
Visibility(
visible: _isProgressVisible,
child: CircularProgressIndicator(),
)
]
)
and I set _isProgressVisible to true and false:
if (_email.isNotEmpty && _password.isNotEmpty) {
setState(() {
_isProgressVisible = true;
});
FirebaseAuth mAuth = FirebaseAuth.instance;
UserCredential credential = await mAuth.createUserWithEmailAndPassword(email: _email, password: _password);
print(credential.user!.email);
setState(() {
_isProgressVisible = false;
});
}

Answer 1

You are not showing the returned widget anywhere, startProgressIndicator() returns the widget but you're just calling not rendering it,
Either use like this
showCupertinoDialog(
useRootNavigator: true,
barrierDismissible: false,
context: context,
builder: (context) {
return startProgressIndicator();
},
);
If you want to show that somewhere else you can do that like this
Container(
margin: const EdgeInsets.all(16),
child: Column(children: [
Visibility(
visible: showIndicator,
child: startProgressIndicator()),
const SizedBox(height: 10),
RaisedButton(
child: const Text('Here'),
onPressed: () => setState(() => showIndicator = !showIndicator),
)
]),
);

Answer 2

return startProgressIndicator();
That's just simple mistake
You have to return widget;