Dart override method on the fly (e.g. JAVA)

Question

Is there a way to override a method in Dart as JAVA, for example:

public class A {
    public void handleLoad() {
    }
}

And when overriding:

A a = new A() {
    @Override
    public void handleLoad() {
        // do some code
    }
};

Answer 1

No, Dart has no anonymous classes. You must create a class that extends Aand creates it.

Answer 2

No, but this is much less useful in Dart, because you can simply reassign the function:

typedef void PrintMsg(msg);

class Printer {
  PrintMsg foo = (m) => print(m);
}

main() {
  Printer p = new Printer()
  ..foo('Hello') // Hello
  ..foo = ((String msg) => print(msg.toUpperCase()))
  ..foo('Hello'); //HELLO
}

However, you will need an additional template to access the instance.