Dart DocumentationsignalsSignal

Signal class

A Signal that can be subscribed to and emitted.

For example:

var s = new Signal();
s.on((arg) => print('Emitted signal with arg: $arg'));
s.emit(1)
> Emitted signal with arg: 1
class Signal {

 final List<Callback> subscriptions = <Callback>[];

 /**
  * Emits the signal by calling all subscribers with the given argument.
  */
 emit(dynamic argument) => subscriptions.forEach((s) => s(argument));

 /**
  * Connects a callback to this signal.
  */
 on(Callback callback) => subscriptions.add(callback);

}

Properties

final List<Callback> subscriptions #

final List<Callback> subscriptions = <Callback>[];

Methods

emit(argument) #

Emits the signal by calling all subscribers with the given argument.

emit(dynamic argument) => subscriptions.forEach((s) => s(argument));

on(Callback callback) #

Connects a callback to this signal.

on(Callback callback) => subscriptions.add(callback);