Java tutorial
/* * Copyright 2008 Google Inc. * * Licensed 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 com.nanosim.client.content.other; import com.google.gwt.event.dom.client.ChangeEvent; import com.google.gwt.event.dom.client.ChangeHandler; import com.google.gwt.i18n.client.Constants; import com.google.gwt.user.client.Command; import com.google.gwt.user.client.Cookies; import com.google.gwt.user.client.DeferredCommand; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.ui.Button; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.user.client.ui.Grid; import com.google.gwt.user.client.ui.ListBox; import com.google.gwt.user.client.ui.TextBox; import com.google.gwt.user.client.ui.Widget; import com.nanosim.client.ContentWidget; import com.nanosim.client.NanosimAnnotations.NanosimData; import com.nanosim.client.NanosimAnnotations.NanosimSource; import java.util.Collection; import java.util.Date; /** * Example file. */ public class CwCookies extends ContentWidget { /** * The constants used in this Content Widget. */ @NanosimSource public static interface CwConstants extends Constants, ContentWidget.CwConstants { String cwCookiesDeleteCookie(); String cwCookiesDescription(); String cwCookiesExistingLabel(); String cwCookiesInvalidCookie(); String cwCookiesName(); String cwCookiesNameLabel(); String cwCookiesSetCookie(); String cwCookiesValueLabel(); } /** * The timeout before a cookie expires, in milliseconds. Current one day. */ @NanosimData private static final int COOKIE_TIMEOUT = 1000 * 60 * 60 * 24; /** * An instance of the constants. */ @NanosimData private CwConstants constants; /** * A {@link TextBox} that holds the name of the cookie. */ @NanosimData private TextBox cookieNameBox = null; /** * A {@link TextBox} that holds the value of the cookie. */ @NanosimData private TextBox cookieValueBox = null; /** * The {@link ListBox} containing existing cookies. */ @NanosimData private ListBox existingCookiesBox = null; /** * Constructor. * * @param constants the constants */ public CwCookies(CwConstants constants) { super(constants); this.constants = constants; } @Override public String getDescription() { return constants.cwCookiesDescription(); } @Override public String getName() { return constants.cwCookiesName(); } @Override public boolean hasStyle() { return false; } /** * Initialize this example. */ @NanosimSource @Override public Widget onInitialize() { // Create the panel used to layout the content Grid mainLayout = new Grid(3, 3); // Display the existing cookies existingCookiesBox = new ListBox(); Button deleteCookieButton = new Button(constants.cwCookiesDeleteCookie()); deleteCookieButton.addStyleName("sc-FixedWidthButton"); mainLayout.setHTML(0, 0, "<b>" + constants.cwCookiesExistingLabel() + "</b>"); mainLayout.setWidget(0, 1, existingCookiesBox); mainLayout.setWidget(0, 2, deleteCookieButton); // Display the name of the cookie cookieNameBox = new TextBox(); mainLayout.setHTML(1, 0, "<b>" + constants.cwCookiesNameLabel() + "</b>"); mainLayout.setWidget(1, 1, cookieNameBox); // Display the name of the cookie cookieValueBox = new TextBox(); Button setCookieButton = new Button(constants.cwCookiesSetCookie()); setCookieButton.addStyleName("sc-FixedWidthButton"); mainLayout.setHTML(2, 0, "<b>" + constants.cwCookiesValueLabel() + "</b>"); mainLayout.setWidget(2, 1, cookieValueBox); mainLayout.setWidget(2, 2, setCookieButton); // Add a handler to set the cookie value setCookieButton.addClickHandler(new ClickHandler() { public void onClick(ClickEvent event) { String name = cookieNameBox.getText(); String value = cookieValueBox.getText(); Date expires = new Date((new Date()).getTime() + COOKIE_TIMEOUT); // Verify the name is valid if (name.length() < 1) { Window.alert(constants.cwCookiesInvalidCookie()); return; } // Set the cookie value Cookies.setCookie(name, value, expires); refreshExistingCookies(name); } }); // Add a handler to select an existing cookie existingCookiesBox.addChangeHandler(new ChangeHandler() { public void onChange(ChangeEvent event) { updateExstingCookie(); } }); // Add a handler to delete an existing cookie deleteCookieButton.addClickHandler(new ClickHandler() { public void onClick(ClickEvent event) { int selectedIndex = existingCookiesBox.getSelectedIndex(); if (selectedIndex > -1 && selectedIndex < existingCookiesBox.getItemCount()) { String cookieName = existingCookiesBox.getValue(selectedIndex); Cookies.removeCookie(cookieName); existingCookiesBox.removeItem(selectedIndex); updateExstingCookie(); } } }); // Return the main layout refreshExistingCookies(null); return mainLayout; } /** * Refresh the list of existing cookies. * * @param selectedCookie the cookie to select by default */ @NanosimSource private void refreshExistingCookies(String selectedCookie) { // Clear the existing cookies existingCookiesBox.clear(); // Add the cookies int selectedIndex = 0; Collection<String> cookies = Cookies.getCookieNames(); for (String cookie : cookies) { existingCookiesBox.addItem(cookie); if (cookie.equals(selectedCookie)) { selectedIndex = existingCookiesBox.getItemCount() - 1; } } // Select the index of the selectedCookie. Use a DeferredCommand to give // the options time to register in Opera. final int selectedIndexFinal = selectedIndex; DeferredCommand.addCommand(new Command() { public void execute() { // Select the default cookie if (selectedIndexFinal < existingCookiesBox.getItemCount()) { existingCookiesBox.setSelectedIndex(selectedIndexFinal); } // Display the selected cookie value updateExstingCookie(); } }); } /** * Retrieve the value of the existing cookie and put it into to value label. */ @NanosimSource private void updateExstingCookie() { // Cannot update if there are no items if (existingCookiesBox.getItemCount() < 1) { cookieNameBox.setText(""); cookieValueBox.setText(""); return; } int selectedIndex = existingCookiesBox.getSelectedIndex(); String cookieName = existingCookiesBox.getValue(selectedIndex); String cookieValue = Cookies.getCookie(cookieName); cookieNameBox.setText(cookieName); cookieValueBox.setText(cookieValue); } }