CancelEventIfAjaxListener (Wicket Core 9.0.0-M1 API)

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

All Implemented Interfaces:

java.io.Serializable, IAjaxCallListener, IComponentAwareHeaderContributor, org.apache.wicket.util.io.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

Constructors
Constructor Description

CancelEventIfAjaxListener()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`java.lang.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, getDoneHandler, getFailureHandler, getInitHandler, getPrecondition, getSuccessHandler, onAfter, onBefore, onBeforeSend, onComplete, onDone, onFailure, onInit, 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 java.lang.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:
    
    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.