com.google.gwt.event.shared
Class ResettableEventBus

java.lang.Object
  com.google.gwt.event.shared.EventBus
      com.google.gwt.event.shared.ResettableEventBus

All Implemented Interfaces:

HasHandlers

public class ResettableEventBus
extends EventBus

Wraps an EventBus to hold on to any HandlerRegistrations, so that they can easily all be cleared at once.

ResettableEventBus

public ResettableEventBus(EventBus wrappedBus)

addHandler

public <H extends EventHandler> HandlerRegistration addHandler(GwtEvent.Type<H> type,
                                                               H handler)

Description copied from class: EventBus

Adds an unfiltered handler to receive events of this type from all sources.

It is rare to call this method directly. More typically a GwtEvent subclass will provide a static register method, or a widget will accept handlers directly.

A tip: to make a handler de-register itself, the following works:

new MyHandler() {
  HandlerRegistration reg = MyEvent.register(eventBus, this);
 
  public void onMyThing(MyEvent event) {
    /* do your thing */
    reg.removeHandler();
  }
 };
 

Specified by:

addHandler in class EventBus

Type Parameters:

H - The type of handler

Parameters:

type - the event type associated with this handler

handler - the handler

Returns:

the handler registration, can be stored in order to remove the handler later

addHandlerToSource

public <H extends EventHandler> HandlerRegistration addHandlerToSource(GwtEvent.Type<H> type,
                                                                       java.lang.Object source,
                                                                       H handler)

Description copied from class: EventBus

Adds a handler to receive events of this type from the given source.

It is rare to call this method directly. More typically a GwtEvent subclass will provide a static register method, or a widget will accept handlers directly.

Specified by:

addHandlerToSource in class EventBus

Type Parameters:

H - The type of handler

Parameters:

type - the event type associated with this handler

source - the source associated with this handler

handler - the handler

Returns:

the handler registration, can be stored in order to remove the handler later

fireEvent

public void fireEvent(GwtEvent<?> event)

Description copied from class: EventBus

Fires the event from no source. Only unfiltered handlers will receive it.

Specified by:

fireEvent in interface HasHandlers

Specified by:

fireEvent in class EventBus

Parameters:

event - the event to fire

fireEventFromSource

public void fireEventFromSource(GwtEvent<?> event,
                                java.lang.Object source)

Description copied from class: EventBus

Fires the given event to the handlers listening to the event's type.

Any exceptions thrown by handlers will be bundled into a UmbrellaException and then re-thrown after all handlers have completed. An exception thrown by a handler will not prevent other handlers from executing.

Specified by:

fireEventFromSource in class EventBus

Parameters:

event - the event to fire

removeHandlers

public void removeHandlers()

Remove all handlers that have been added through this wrapper.