Class GwtEvent<H extends EventHandler>

java.lang.Object
com.google.web.bindery.event.shared.Event<H>
com.google.gwt.event.shared.GwtEvent<H>
Type Parameters:
H - handler type
Direct Known Subclasses:
AbstractHasData.RedrawEvent, AttachEvent, BeforeSelectionEvent, CellPreviewEvent, CloseEvent, ColumnSortEvent, DomEvent, Event.NativePreviewEvent, FormPanel.SubmitCompleteEvent, FormPanel.SubmitEvent, HighlightEvent, InitializeEvent, LoadingStateChangeEvent, OpenEvent, PlaceChangeEvent, PlaceChangeRequestEvent, RangeChangeEvent, ResizeEvent, RowCountChangeEvent, RowHoverEvent, SelectionChangeEvent, SelectionEvent, ShowRangeEvent, ValueChangeEvent, Window.ClosingEvent, Window.ScrollEvent

public abstract class GwtEvent<H extends EventHandler> extends Event<H>
Root of all GWT widget and dom events sourced by a HandlerManager. All GWT events are considered dead and should no longer be accessed once the HandlerManager which originally fired the event finishes with it. That is, don't hold on to event objects outside of your handler methods.

There is no need for an application's custom event types to extend GwtEvent. Prefer Event instead.

  • Constructor Details

    • GwtEvent

      protected GwtEvent()
      Constructor.
  • Method Details

    • getAssociatedType

      public abstract GwtEvent.Type<H> getAssociatedType()
      Description copied from class: Event
      Returns the Event.Type used to register this event, allowing an EventBus to find handlers of the appropriate class.
      Specified by:
      getAssociatedType in class Event<H extends EventHandler>
      Returns:
      the type
    • getSource

      public Object getSource()
      Description copied from class: Event
      Returns the source for this event. The type and meaning of the source is arbitrary, and is most useful as a secondary key for handler registration. (See EventBus.addHandlerToSource(com.google.web.bindery.event.shared.Event.Type<H>, java.lang.Object, H), which allows a handler to register for events of a particular type, tied to a particular source.)

      Note that the source is actually set at dispatch time, e.g. via EventBus.fireEventFromSource(Event, Object).

      Overrides:
      getSource in class Event<H extends EventHandler>
      Returns:
      object representing the source of this event
    • assertLive

      protected void assertLive()
      Asserts that the event still should be accessed. All events are considered to be "dead" after their original handler manager finishes firing them. An event can be revived by calling revive().
    • dispatch

      protected abstract void dispatch(H handler)
      Should only be called by HandlerManager. In other words, do not use or call.
      Specified by:
      dispatch in class Event<H extends EventHandler>
      Parameters:
      handler - handler
      See Also:
    • isLive

      protected final boolean isLive()
      Is the event current live?
      Returns:
      whether the event is live
    • kill

      protected void kill()
      Kill the event. After the event has been killed, users cannot really on its values or functions being available.
    • revive

      protected void revive()
      Revives the event. Used when recycling event instances.
    • overrideSource

      void overrideSource(Object source)