Minimal reproducible code:
Future<void> foo(int i) async => print(i);
Future<void> bar(double d, bool b) async => print(b);
@override
Widget build(BuildContext context) {
var flag = true;
var onPressed = flag ? foo(1) : bar(0.0, true);
return Scaffold(
body: RaisedButton(
onPressed: () => onPressed,
child: Text('Button'),
),
);
}
Problem:
The method gets called during build process because I'm åctually calling foo(1)
. How to resolve this issue? I only want to get it done using one variable as shown above.
It seems like there is no way to do this. The closest thing that can be done is to change my variable to a method.
So,
Instead of
var onPressed = flag ? foo(1) : bar(0.0, true);
Use
void onPressed () => flag ? foo(1) : bar(0.0, true);
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