How to pass a function as a parameter in widget? - flutter

Question

I created a widget and I want to pass a function to this widget, but when I try to do this I get this error.
Moreover when this function is passed to a widget it is automatically used, because it debugPrint "MONEY CHANGED".
This is the function code:
class Functions {
changeMoney(int money) {
Boxes.getCharacter().get(0)!.money =
Boxes.getCharacter().get(0)!.money + money;
debugPrint("MONEY CHANGED");
}
}
And this is widget's code:
class DialogButton extends StatefulWidget {
const DialogButton(
{Key? key,
required this.answer,
required this.function,
required this.possible})
: super(key: key);
final String answer;
final Function function;
final bool possible;
#override
State<DialogButton> createState() => _DialogButtonState();
}
class _DialogButtonState extends State<DialogButton> {
#override
Widget build(BuildContext context) {
return Padding(
padding: const EdgeInsets.symmetric(vertical: 6),
child: ElevatedButton(
onPressed: () => {
Navigator.of(context, rootNavigator: true).pop(),
widget.function
},
child: Padding(
padding: const EdgeInsets.symmetric(vertical: 18.0),
child: Row(children: [
Expanded(child: Container()),
Text(
widget.answer,
style: rajdhaniStyle(weight: FontWeight.w600, size: 18),
),
Expanded(child: Container()),
]),
)),
);
}
}
So the question is how should i correctly pass a function inside widget without automatically make it turn on the function and without getting an error?

Answer 1

If the function have parameter, then the received widget (here is DialogButton) also need to declare parameter type. Example, the function is: void doSomething(String hehe, int yolo) {}. Then your DialogButton should be declare as Function(String, int) onTap.
More details, in first screen, you can call DialogButton like this:
class Screen1 extends StatelessWidget {
#override
build(...) {
// do something
DialogButton(
answer: "your answer",
function: (double money) {},
possible: true,
)
}
}
Otherwise, if you want to split/separate the function (not write-in-line like above), you could do as follow:
class Screen1 extends StatelessWidget {
#override
build(...) {
// do something
DialogButton(
answer: "your answer",
function: myFunction,
possible: true,
)
}
myFunction(double money) {}
}