Package com.google.gwt.place.shared

Class PlaceChangeRequestEvent

java.lang.Object

com.google.web.bindery.event.shared.Event<PlaceChangeRequestEvent.Handler>

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.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	PlaceChangeRequestEvent.Handler	Implemented by handlers of PlaceChangeRequestEvent.

Nested classes/interfaces inherited from class com.google.gwt.event.shared.GwtEvent

GwtEvent.Type<H>

Field Summary

Fields

Modifier and Type	Field	Description
static final GwtEvent.Type<PlaceChangeRequestEvent.Handler>	TYPE	A singleton instance of Type<Handler>.

Constructor Summary

Constructors

Constructor	Description
PlaceChangeRequestEvent(Place newPlace)	Constructs a PlaceChangeRequestEvent for the given Place.

Method Summary

Modifier and Type	Method	Description
protected void	dispatch(PlaceChangeRequestEvent.Handler handler)	Should only be called by HandlerManager.
GwtEvent.Type<PlaceChangeRequestEvent.Handler>	getAssociatedType()	Returns the Event.Type used to register this event, allowing an EventBus to find handlers of the appropriate class.
Place	getNewPlace()	Returns the place we may navigate to, or null on window close.
String	getWarning()	Returns the warning message to show the user before allowing the place change, or null if none has been set.
void	setWarning(String warning)	Set a message to warn the user that it might be unwise to navigate away from the current place, e.g.

Methods inherited from class com.google.gwt.event.shared.GwtEvent

assertLive, getSource, isLive, kill, revive

Methods inherited from class com.google.web.bindery.event.shared.Event

setSource, toDebugString, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

TYPE

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

A singleton instance of Type<Handler>.

Constructor Details

PlaceChangeRequestEvent

public PlaceChangeRequestEvent(Place newPlace)

Constructs a PlaceChangeRequestEvent for the given Place.

Parameters:

newPlace - a Place instance

Method Details

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 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(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)