Java tutorial
/********************************************** * Copyright (C) 2010 Lukas Laag * This file is part of vectomatic2. * * vectomatic2 is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * vectomatic2 is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with vectomatic2. If not, see http://www.gnu.org/licenses/ **********************************************/ package org.vectomatic.svg.edit.client; import java.io.IOException; import java.util.Iterator; import org.vectomatic.dom.svg.OMAttr; import org.vectomatic.dom.svg.OMElement; import org.vectomatic.dom.svg.OMNode; import org.vectomatic.dom.svg.impl.SVGParserImpl; import org.vectomatic.dom.svg.utils.DOMHelper; import org.vectomatic.dom.svg.utils.XPathPrefixResolver; import com.extjs.gxt.ui.client.Style.Scroll; import com.extjs.gxt.ui.client.data.BeanModel; import com.extjs.gxt.ui.client.data.BeanModelFactory; import com.extjs.gxt.ui.client.data.BeanModelLookup; import com.extjs.gxt.ui.client.data.BeanModelTag; import com.extjs.gxt.ui.client.event.ButtonEvent; import com.extjs.gxt.ui.client.event.Events; import com.extjs.gxt.ui.client.event.Listener; import com.extjs.gxt.ui.client.event.SelectionChangedEvent; import com.extjs.gxt.ui.client.event.SelectionListener; import com.extjs.gxt.ui.client.store.ListStore; import com.extjs.gxt.ui.client.util.Format; import com.extjs.gxt.ui.client.widget.Dialog; import com.extjs.gxt.ui.client.widget.ListView; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Document; import com.google.gwt.http.client.Request; import com.google.gwt.http.client.RequestBuilder; import com.google.gwt.http.client.RequestCallback; import com.google.gwt.http.client.RequestException; import com.google.gwt.http.client.Response; /** * Dialog to display the OpenClipArt 'new svg' RSS feed. * @author laaglu */ public class RSSReader extends Dialog { /** * Bean to represent a single entry in the * OpenClipArt 'new svg' RSS feed. * @author laaglu */ public static class RSSEntry implements BeanModelTag { private String pngPath; private String svgPath; public RSSEntry() { } public void setPngPath(String pngPath) { this.pngPath = pngPath; } public String getPngPath() { return pngPath; } public void setSvgPath(String svgPath) { this.svgPath = svgPath; } public String getName() { int index = svgPath.lastIndexOf('/'); return (index != -1) ? svgPath.substring(1 + index) : svgPath; } public String getSvgPath() { return svgPath; } } /** * The list view */ private ListView<BeanModel> view; /** * A store from which the list view fetches * RSS records */ private ListStore<BeanModel> store; /** * A bean factory to wrap RSSEntry into BeanModel * to make them compatible with ListView */ private BeanModelFactory beanFactory; public RSSReader() { super(); okText = AppConstants.INSTANCE.openButton(); cancelText = AppConstants.INSTANCE.cancelButton(); setButtons(Dialog.OKCANCEL); setScrollMode(Scroll.AUTO); setHideOnButtonClick(true); setHeading(AppConstants.INSTANCE.openRssFeedMenuItem()); setModal(true); setSize(520, 300); getButtonById(OK).addSelectionListener(new SelectionListener<ButtonEvent>() { @Override public void componentSelected(ButtonEvent ce) { for (BeanModel beanModel : view.getSelectionModel().getSelectedItems()) { RSSEntry rssEntry = (RSSEntry) beanModel.getBean(); VectomaticApp2.APP.load(rssEntry.getSvgPath()); } } }); beanFactory = BeanModelLookup.get().getFactory(RSSEntry.class); store = new ListStore<BeanModel>(); view = new ListView<BeanModel>() { @Override protected BeanModel prepareData(BeanModel model) { String s = model.get("name"); model.set("shortName", Format.ellipse(s, 15)); return model; } }; view.setTemplate(getTemplate()); view.setStore(store); view.setItemSelector("div.thumb-wrap"); view.getSelectionModel().addListener(Events.SelectionChange, new Listener<SelectionChangedEvent<BeanModel>>() { public void handleEvent(SelectionChangedEvent<BeanModel> be) { BeanModel beanModel = be.getSelectedItem(); if (beanModel != null) { RSSEntry rssEntry = (RSSEntry) beanModel.getBean(); GWT.log("Selected: " + rssEntry.getName()); } } }); add(view); load(); } public void load() { final String url = "http://www.openclipart.org/rss/new.xml"; String resourceUrl = GWT.getHostPageBaseURL() + "fetch?url=" + url + "&type=text/xml"; RequestBuilder requestBuilder = new RequestBuilder(RequestBuilder.GET, resourceUrl); requestBuilder.setCallback(new RequestCallback() { public void onError(Request request, Throwable e) { GWT.log("Cannot fetch " + url, e); VectomaticApp2.APP.info(AppConstants.INSTANCE.openRssFeedMenuItem(), AppMessages.INSTANCE.loadErrorMessage(url, e.getMessage())); } private void onSuccess(Request request, Response response) { // Create a store of BeanModel of RSSEntry SVGParserImpl impl = GWT.create(SVGParserImpl.class); Document doc = impl.parseFromString(response.getText(), "text/xml").cast(); OMElement root = OMNode.convert(doc.getDocumentElement()); Iterator<OMAttr> iterator = DOMHelper.evaluateXPath(root, "//rss/channel/item/enclosure/@url", null); while (iterator.hasNext()) { RSSEntry rssEntry = new RSSEntry(); rssEntry.setSvgPath(iterator.next().getValue()); store.add(beanFactory.createModel(rssEntry)); } iterator = DOMHelper.evaluateXPath(root, "//rss/channel/item/media:thumbnail/@url", new XPathPrefixResolver() { @Override public String resolvePrefix(String prefix) { if ("media".equals(prefix)) { return "http://search.yahoo.com/mrss/"; } return null; } }); int index = 0; while (iterator.hasNext()) { BeanModel beanModel = store.getAt(index++); RSSEntry rssEntry = (RSSEntry) beanModel.getBean(); rssEntry.setPngPath(iterator.next().getValue()); store.update(beanModel); } } public void onResponseReceived(Request request, Response response) { if (response.getStatusCode() == Response.SC_OK) { onSuccess(request, response); } else { onError(request, new IOException( AppMessages.INSTANCE.httpErrorMessage(Integer.toString(response.getStatusCode())))); } } }); try { requestBuilder.send(); } catch (RequestException e) { GWT.log("Cannot fetch " + url, e); VectomaticApp2.APP.info(AppConstants.INSTANCE.openRssFeedMenuItem(), AppMessages.INSTANCE.loadErrorMessage(url, e.getMessage())); } } private static native String getTemplate() /*-{ return ['<tpl for=".">', '<div class="thumb-wrap" id="{svgPath}">', '<div class="thumb"><img src="{pngPath}" title="{name}"></div>', '<span class="x-editable">{shortName}</span></div>', '</tpl>', '<div class="x-clear"></div>'].join(""); }-*/; }