Calling a ChangeNotifier method in non widget instance

How can I call a ChangeNotifier method from a non-widget instance?
Everywhere people have been calling the method inside a ChnageNotifier class using a Consumer, which is inside a widget. But I want to call the method without using Consumer or calling it from a non-widget instance. If anyone help, please have a look.

Class Example with ChangeNotifier{
  ...
  void exampleMethod(){
    // inside the method
    notifyListeners();
  }
}

Is this Flutter? [you really need to tell us what programming language you are using]

Oh… I am sorry! The language used is flutter.

Not a Flutter expert, but according to this, you should be able to invoke notifyListeners() from your exampleMethod() as in your original post.

Presumably its not doing what you want, so you’ll have to explain the problem with a little more detail …