ajaxbutton.java

Wicket一个开发Java Web应用程序框架。它使得开发web应用程序变得容易而轻松。 Wicket利用一个POJO data beans组件使得它可以与任何持久层技术相结合。

/*
 * 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.markup.html.form;

import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.ajax.IAjaxCallDecorator;
import org.apache.wicket.ajax.form.AjaxFormSubmitBehavior;
import org.apache.wicket.markup.html.form.Button;
import org.apache.wicket.markup.html.form.Form;
import org.apache.wicket.util.string.AppendingStringBuffer;

/**
 * A button that submits the form via ajax. Since this button takes the form as a constructor
 * argument it does not need to be added to it unlike the {@link Button} component.
 * 
 * @since 1.3
 * 
 * @author Igor Vaynberg (ivaynberg)
 */
public abstract class AjaxButton extends Button
{
	private static final long serialVersionUID = 1L;

	private final Form form;

	/**
	 * Construct.
	 * 
	 * @param id
	 */
	public AjaxButton(String id)
	{
		this(id, null);
	}

	/**
	 * Returns the form if it was set in constructor, otherwise returns the form nearest in parent
	 * hierarchy.
	 * 
	 * @see org.apache.wicket.markup.html.form.FormComponent#getForm()
	 */
	public Form getForm()
	{
		if (form != null)
		{
			return form;
		}
		else
		{
			return super.getForm();
		}
	}

	/**
	 * Construct.
	 * 
	 * @param id
	 * @param form
	 */
	public AjaxButton(String id, final Form form)
	{
		super(id);
		this.form = form;

		add(new AjaxFormSubmitBehavior(form, "onclick")
		{

			private static final long serialVersionUID = 1L;

			protected void onSubmit(AjaxRequestTarget target)
			{
				AjaxButton.this.onSubmit(target, AjaxButton.this.getForm());
			}

			protected void onError(AjaxRequestTarget target)
			{
				AjaxButton.this.onError(target, AjaxButton.this.getForm());
			}

			protected CharSequence getEventHandler()
			{
				return new AppendingStringBuffer(super.getEventHandler()).append("; return false;");
			}

			protected IAjaxCallDecorator getAjaxCallDecorator()
			{
				return AjaxButton.this.getAjaxCallDecorator();
			}

		});

	}

	/**
	 * Returns the {@link IAjaxCallDecorator} that will be used to modify the generated javascript.
	 * This is the preferred way of changing the javascript in the onclick handler
	 * 
	 * @return call decorator used to modify the generated javascript or null for none
	 */
	protected IAjaxCallDecorator getAjaxCallDecorator()
	{
		return null;
	}

	/**
	 * Listener method invoked on form submit with no errors
	 * 
	 * @param target
	 * @param form
	 */
	protected abstract void onSubmit(AjaxRequestTarget target, Form form);

	/**
	 * Listener method invoked on form submit with errors
	 * 
	 * @param target
	 * @param form
	 * 
	 * TODO 1.3: Make abstract to be consistent with onSubmit()
	 */
	protected void onError(AjaxRequestTarget target, Form form)
	{

	}

}