/* * Copyright 2006 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.google.gwt.sample.mail.client;import com.google.gwt.user.client.ui.Composite;import com.google.gwt.user.client.ui.Tree;import com.google.gwt.user.client.ui.TreeItem;/** * A tree displaying a set of email folders. */public class Mailboxes extends Composite {  private Tree tree = new Tree();  public Mailboxes() {    TreeItem root = new TreeItem(imageItemHTML("home.gif", "foo@example.com"));    tree.addItem(root);    addImageItem(root, "Inbox");    addImageItem(root, "Drafts");    addImageItem(root, "Templates");    addImageItem(root, "Sent");    addImageItem(root, "Trash");    root.setState(true);    initWidget(tree);  }  /**   * A helper method to simplify adding tree items that have attached images.   * {@link #addImageItem(TreeItem, String) code}   *    * @param root the tree item to which the new item will be added.   * @param title the text associated with this item.   */  private TreeItem addImageItem(TreeItem root, String title) {    TreeItem item = new TreeItem(imageItemHTML(title + ".gif", title));    root.addItem(item);    return item;  }  /**   * Generates HTML for a tree item with an attached icon.   *    * @param imageUrl the url of the icon image   * @param title the title of the item   * @return the resultant HTML   */  private String imageItemHTML(String imageUrl, String title) {    return "<span><img style='margin-right:4px' src='" + imageUrl.toLowerCase()        + "'>" + title + "</span>";  }}