MessageHandlerBuilder<M> class

Provides methods for describing how a state behaves in response to a message of type M.

A MessageHandlerBuilder is provided to the build callback provided to StateBuilder.onMessage, and is used to describe how messages of a particular type are handled by a state.

class MyMessage {}
var state1 = StateKey('s1');
var state2 = StateKey('s2');
var builder = StateTreeBuilder(initialState: state1);
builder.state(state1, (b) {
  // Describe how state responds to MyMessage messages
  b.onMessage<MyMessage>((b) => b.goTo(state2));
});