How a closure / arrow function can access a variable where the closure will be executed?-CodePudding

In Dart/Flutter I need that a closure / arrow function passed to a class instance would be able to use a variable of that class instance. Is there a way?

For example, I have a widget that will have a context in build method, as usual. I need to pass a closure to the widget and the closure needs to use that context.

CodePudding user response：

If the class is yours then you can do

class MyWidget extends StatelessWidget {
  final void Function(BuildContext) closure;

  const MyWidget({required this.closure, Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    closure(context);
    return ...
  }
}

void closure(BuildContext context) {
  // called from MyWidget, context is also from there.
}


// pass function to class
const MyWidget(closure: closure);