How can I call show dialog using onpressed inside body of build - flutter

Question

I tried using the following function inside build body.But it throws error saying
The argument type 'Future<void> Function(BuildContext)' can't be assigned to the parameter type 'void Function()'
Future<void> confirmation(BuildContext context) async {
return await showDialog<void>(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return AlertDialog(
backgroundColor: Colors.black54,
content: Center(
child: Text(
"Please Wait....",
style: TextStyle(color: Colors.blueAccent),
)));
});
}
class Trial extends StatelessWidget {
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
appBar: AppBar(title: Text('Request Processed')),
body: Center(
child: Flatbutton(onPressed: confirmation,child: Text('Click me')), //this onpressed shows error
),
),
);
}
}
I have tried calling the same function from appBar action widget icon and it didn't throw any error.On using in build function only it throws error. Why is that so?

Answer 1

Try to call it like this
class Trial extends StatelessWidget {
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
appBar: AppBar(title: Text('Request Processed')),
body: Center(
child: Flatbutton(onPressed: () {confirmation(context);},child: Text('Click me')), //this onpressed shows error
),
),
);
}
}
It seems the same but it saved me a lot of time. Let me know:)

Answer 2

Pass the context while calling it. Like this ()=>confirmation(context)
class Trial extends StatelessWidget {
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
appBar: AppBar(title: Text('Request Processed')),
body: Center(
child: Flatbutton(onPressed: ()=>confirmation(context),child: Text('Click me')), //this onpressed shows error
),
),
);
}
}