com.google.gwt.place.shared
Class PlaceChangeRequestEvent

java.lang.Object
  com.google.web.bindery.event.shared.Event<H>
      com.google.gwt.event.shared.GwtEvent<PlaceChangeRequestEvent.Handler>
          com.google.gwt.place.shared.PlaceChangeRequestEvent

public class PlaceChangeRequestEvent
extends GwtEvent<PlaceChangeRequestEvent.Handler>

Event thrown when the user may go to a new place in the app, or tries to leave it. Receivers can call setWarning(String) request that the user be prompted to confirm the change.

TYPE

public static final GwtEvent.Type<PlaceChangeRequestEvent.Handler> TYPE

A singleton instance of Type<Handler>.

PlaceChangeRequestEvent

public PlaceChangeRequestEvent(Place newPlace)

Constructs a PlaceChangeRequestEvent for the given Place.

Parameters:

newPlace - a Place instance

getAssociatedType

public GwtEvent.Type<PlaceChangeRequestEvent.Handler> 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 GwtEvent<PlaceChangeRequestEvent.Handler>

Returns:

the type

getNewPlace

public Place getNewPlace()

Returns the place we may navigate to, or null on window close.

Returns:

a Place instance

getWarning

public java.lang.String getWarning()

Returns the warning message to show the user before allowing the place change, or null if none has been set.

Returns:

the warning message as a String

See Also:

setWarning(String)

setWarning

public void setWarning(java.lang.String warning)

Set a message to warn the user that it might be unwise to navigate away from the current place, e.g. due to unsaved changes. If the user clicks okay to that message, navigation will be canceled.

Calling with a null warning is the same as not calling the method at all -- the user will not be prompted.

Only the first non-null call to setWarning has any effect. That is, once the warning message has been set it cannot be cleared.

Parameters:

warning - the warning message as a String

See Also:

getWarning()

dispatch

protected void dispatch(PlaceChangeRequestEvent.Handler handler)

Description copied from class: GwtEvent

Should only be called by HandlerManager. In other words, do not use or call.

Specified by:

dispatch in class GwtEvent<PlaceChangeRequestEvent.Handler>

Parameters:

handler - handler

See Also:

EventBus.dispatchEvent(Event, Object)