/*
* 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.click.examples.page.ajax;
import java.util.List;
import java.util.Map;
import javax.annotation.Resource;
import org.apache.click.element.Element;
import org.apache.click.element.JsImport;
import org.apache.click.element.JsScript;
import org.apache.click.examples.page.BorderPage;
import org.apache.click.examples.service.CustomerService;
import org.apache.click.util.ClickUtils;
import org.apache.commons.lang.math.NumberUtils;
import org.springframework.stereotype.Component;
/**
* Demonstrates how to to dynamically load more customer while scrolling down
* the Page.
*/
@Component
public class AjaxLiveScroller extends BorderPage {
private static final long serialVersionUID = 1L;
@Resource(name="customerService")
private CustomerService customerService;
// Specifies the number of customers to retrieve at a time
private int pageSize = 10;
// Event Handlers --------------------------------------------------------
@Override
public void onGet() {
// Check if the offset parameter was received.
int offset = NumberUtils.toInt(getContext().getRequest().getParameter("offset"));
if (offset < 0) {
// If no offset was given, we assume this is not an Ajax request
// and set the offset to 0
offset = 0;
// We also set a message to display
addModel("msg", "Top customers");
}
// Return customers between the given offset and pageSize
addModel("customers", customerService.getTopCustomersForPage(offset, pageSize));
}
@Override
public List<Element> getHeadElements() {
// Lazily load head elements and ensure they are only loaded once
if (headElements == null) {
headElements = super.getHeadElements();
// Add the jQuery library
headElements.add(new JsImport("/assets/js/jquery-1.3.2.js"));
// Create a default model and add the pageSize variable to pass to
// the JavaScript template: ajax-live-scroller.js
Map model = ClickUtils.createTemplateModel(this, getContext());
model.put("pageSize", pageSize);
// Note the actual JavaScript necessary to setup the dynamic scrolling
// is specified in the Page JavaScript template: ajax-live-scroller.js.
headElements.add(new JsScript("/ajax/ajax-live-scroller.js", model));
}
return headElements;
}
// Public Methods ---------------------------------------------------------
@Override
public String getTemplate() {
// For Ajax requests we want to render the Page template only as there is
// no need to include the Border template in the response
if (getContext().isAjaxRequest()) {
return getPath();
} else {
return super.getTemplate();
}
}
}