Dart/Flutter support for delegates

Question

Does Dart 2.0 support the concept of a delegate? Having reviewed the documentation I assume not. So is this is an omission? Or is there an alternate approach to achieving the same? Possibly using streams?

Solution

The only one that I know of that is delegate "like" is typedef. It really is a way to strongly type callbacks. A common one is WidgetBuilder

typedef Widget WidgetBuilder(BuildContext context);

or the more preferred way of writing a callback

typedef WidgetBuilder = Widget Function(BuildContext context);

But you can also build your own

Comments

[Edman]

What kind of delegation are you looking for?

[Yarm]

A page calls a route which calls another route. Tthen an action pops both the second route and calls a delegate to Also pop the first route.

[matanlurey]

This is unrelated to Dart. You're looking for a Flutter feature?

[Yarm]

No, looking for a language feature (dart) to use with the framework (flutter).