/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.wicket.ajax.form;
import org.apache.wicket.WicketRuntimeException;
import org.apache.wicket.ajax.AjaxEventBehavior;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.markup.html.form.FormComponent;
import org.apache.wicket.markup.html.form.persistence.IValuePersister;
import org.apache.wicket.markup.html.form.validation.IFormValidator;
import org.apache.wicket.util.string.AppendingStringBuffer;
/**
* A behavior that updates the hosting FormComponent via ajax when an event it
* is attached to is triggered. This behavior encapsulates the entire
* form-processing workflow as relevant only to this component so if validation
* is successfull the component's model will be updated according to the
* submitted value.
* <p>
* NOTE: This behavior does not support persisting form component values into
* cookie or other {@link IValuePersister}. If this is necessary please add a
* request for enhancement.
* <p>
* NOTE: This behavior does not validate any {@link IFormValidator}s attached
* to this form even though they may reference the component being updated.
*
* @since 1.2
*
* @author Igor Vaynberg (ivaynberg)
*/
public abstract class AjaxFormComponentUpdatingBehavior extends AjaxEventBehavior
{
/**
* Construct.
*
* @param event
* event to trigger this behavior
*/
public AjaxFormComponentUpdatingBehavior(final String event)
{
super(event);
}
/**
*
* @see org.apache.wicket.behavior.AbstractAjaxBehavior#onBind()
*/
protected void onBind()
{
super.onBind();
if (!(getComponent() instanceof FormComponent))
{
throw new WicketRuntimeException("Behavior " + getClass().getName()
+ " can only be added to an instance of a FormComponent");
}
}
/**
*
* @return FormComponent
*/
protected final FormComponent getFormComponent()
{
return (FormComponent)getComponent();
}
/**
* @see org.apache.wicket.ajax.AjaxEventBehavior#getEventHandler()
*/
protected final CharSequence getEventHandler()
{
return generateCallbackScript(new AppendingStringBuffer("wicketAjaxPost('").append(
getCallbackUrl(false)).append(
"', wicketSerialize(Wicket.$('" + getComponent().getMarkupId()
+ "'))"));
}
/**
* @see org.apache.wicket.ajax.AjaxEventBehavior#onCheckEvent(java.lang.String)
*/
protected void onCheckEvent(String event)
{
if ("href".equalsIgnoreCase(event))
{
throw new IllegalArgumentException(
"this behavior cannot be attached to an 'href' event");
}
}
/**
*
* @see org.apache.wicket.ajax.AjaxEventBehavior#onEvent(org.apache.wicket.ajax.AjaxRequestTarget)
*/
protected final void onEvent(final AjaxRequestTarget target)
{
final FormComponent formComponent = getFormComponent();
try
{
formComponent.inputChanged();
formComponent.validate();
if (formComponent.hasErrorMessage())
{
formComponent.invalid();
onError(target, null);
}
else
{
formComponent.valid();
formComponent.updateModel();
onUpdate(target);
}
}
catch (RuntimeException e)
{
onError(target, e);
}
}
/**
* Listener invoked on the ajax request. This listener is invoked after the
* component's model has been updated.
*
* @param target
*/
protected abstract void onUpdate(AjaxRequestTarget target);
/**
* Called to handle any error resulting from updating form component. Errors
* thrown from {@link #onUpdate(AjaxRequestTarget)} will not be caught here.
*
* The RuntimeException will be null if it was just a validation or conversion
* error of the FormComponent
*
* @param target
* @param e
*/
protected void onError(AjaxRequestTarget target, RuntimeException e)
{
if(e != null) throw e;
}
}