PlatformException throw unexpected - error-handling

Question

I call method in ScopedModel from outside ScopedModel (on button press). But PlatformException is not catch as I expect.
PlatformException is only catch in ScopedModel Method try/catch. It is not catch in button press try/catch.
Button press:
child: RaisedButton(
onPressed: () async {
try {
await loginModel.signInWithGoogle();
} on PlatformException catch (e) {
debugPrint(e.toString());
}
},
ScopedModel Method:
await _signInWithGoogle();
…
Future<void> _signInWithGoogle() async {
…
throw PlatformException(code: ‘Test Exception’);
} on PlatformException catch (e) {
debugPrint(e.toString());
}
I throw PlatformException in ScopedModel to test when exception is throw from this method.
Why there is difference? I want catch PlatformException in button press
Thanks for help!

Answer 1

It should work. See a very simple example:
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
Login userLogin = Login();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Simple exception test',
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () async {
try {
await userLogin.signInWithGoogle();
} on PlatformException catch (e) {
print('Error ...:');
print(e);
}
},
tooltip: 'Increment',
child: Icon(Icons.add),
),
);
}
}
class Login {
Future<void> signInWithGoogle() async {
throw PlatformException(code: 'Test Exception');
}
}