org.apache.wicket.ajax
Class CancelEventIfAjaxListener

java.lang.Object
  org.apache.wicket.ajax.attributes.AjaxCallListener
      org.apache.wicket.ajax.CancelEventIfAjaxListener

All Implemented Interfaces:

Serializable, IAjaxCallListener, IComponentAwareHeaderContributor, IClusterable

public final class CancelEventIfAjaxListener
extends AjaxCallListener

Decorator that can be used to cancel the regular action if ajax call was performed. This allows us to, for example, cancel the default anchor behavior (requesting href url) if an ajax call was made in the onclick event handler. Ajax call cannot be performed if javascript has been turned off or no compatible XmlHttpRequest object can be found. This decorator will make javascript return true if the ajax call was made, and false otherwise.

Since:

6.0

Author:

Igor Vaynberg (ivaynberg)

See Also:

AjaxFallbackLink, Serialized Form

Constructor Summary

CancelEventIfAjaxListener()

Method Summary

CharSequence

getBeforeHandler(Component component) The JavaScript that will be executed before the Ajax call, as early as possible.

Methods inherited from class org.apache.wicket.ajax.attributes.AjaxCallListener

getAfterHandler, getBeforeSendHandler, getCompleteHandler, getFailureHandler, getPrecondition, getSuccessHandler, onAfter, onBefore, onBeforeSend, onComplete, onFailure, onPrecondition, onSuccess, renderHead

Methods inherited from class java.lang.Object

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

Constructor Detail

CancelEventIfAjaxListener

public CancelEventIfAjaxListener()

Method Detail

getBeforeHandler

public CharSequence getBeforeHandler(Component component)

Description copied from interface: IAjaxCallListener

The JavaScript that will be executed before the Ajax call, as early as possible. Even before the preconditions. The script will be executed in a function that receives the following parameters:

1. attrs - the AjaxRequestAttributes as JSON

Specified by:

getBeforeHandler in interface IAjaxCallListener

Overrides:

getBeforeHandler in class AjaxCallListener

Parameters:

component - the Component with the Ajax behavior

Returns:

the JavaScript that will be executed before the Ajax call.