Event<T extends EventArgs> class

Represents an Event as some number of handlers (subscribers) that can be notified when a condition occurs, by using the broadcast method.

See also EventArgs.

Note: the example folder contains an example of the Counter app using Events

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// An example of a simple Event with no argument.
var e = Event();
e.subscribe((args) => print('changed')); // add a handler
e.broadcast(); // broadcast the Event to subscribers
// outputs "changed" to console

// An example of an Event broadcasting a custom argument (see EventArgs).
var e = Event<MyChangedValue>();
e.subscribe((args) => print(args.changedValue)); // add a handler
e.broadcast(MyChangedValue(37)); // broadcast the Event to subscribers
// outputs 37 to console

Constructors

Event.new([String eventName = ""])
Constructor creates a new Event with an optional eventName to identify the Event.

Properties

eventName → String
An optional name for the Event
final
genericType → Type
Gets this Events generic type. If not explicitly set, will be EventArgs, e.g.
no setter
hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
subscriberCount → int
Returns the number of handlers (subscribers).
no setter

Methods

broadcast([dynamic args]) → bool
Broadcast this Event to subscribers, with an optional EventArgs derived argument.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
notifySubscribers([dynamic args]) → bool
Notify subscribers that this Event occurred, with an optional EventArgs derived argument. A direct equivalent of the broadcast method.
subscribe(EventHandler<T> handler) → void
Adds a handler (callback) that will be executed when this Event is raised using the broadcast method.
subscribeStream(StreamSink sink) → void
Subscribes a Stream StreamSink to an Event.
toString() → String
Represent this Event as its (optional) name + Type
override
unsubscribe(EventHandler<T> handler) → bool
Removes a handler previously added to this Event.
unsubscribeAll() → void
Removes all subscribers (handlers).

Operators

operator ==(Object other) → bool
The equality operator.
inherited