Java tutorial
/* * JBoss, Home of Professional Open Source * Copyright 2011 Red Hat Inc. and/or its affiliates and other contributors * as indicated by the @author tags. All rights reserved. * See the copyright.txt in the distribution for a * full listing of individual contributors. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License, v. 2.1. * This program is distributed in the hope that it will be useful, but WITHOUT A * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. * You should have received a copy of the GNU Lesser General Public License, * v.2.1 along with this distribution; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301, USA. */ package org.jboss.ballroom.client.layout; import com.google.gwt.core.client.GWT; import com.google.gwt.core.client.Scheduler; import com.google.gwt.dom.client.EventTarget; import com.google.gwt.event.dom.client.KeyCodes; import com.google.gwt.event.dom.client.KeyDownEvent; import com.google.gwt.event.dom.client.KeyDownHandler; import com.google.gwt.event.dom.client.MouseDownEvent; import com.google.gwt.event.dom.client.MouseDownHandler; import com.google.gwt.event.logical.shared.CloseEvent; import com.google.gwt.event.logical.shared.CloseHandler; import com.google.gwt.event.logical.shared.OpenEvent; import com.google.gwt.event.logical.shared.OpenHandler; import com.google.gwt.event.logical.shared.SelectionEvent; import com.google.gwt.event.logical.shared.SelectionHandler; import com.google.gwt.user.client.DOM; import com.google.gwt.user.client.Element; import com.google.gwt.user.client.Event; import com.google.gwt.user.client.ui.HTMLPanel; import com.google.gwt.user.client.ui.Tree; import com.google.gwt.user.client.ui.TreeItem; import org.jboss.ballroom.client.spi.Framework; import org.jboss.ballroom.client.widgets.icons.DefaultTreeResources; /** * * A tree that's used as a navigation element on the left hand side.<br> * It's driven by a token attribute that's associated with the tree item. * * @see LHSNavTreeItem * @see LHSTreeSection * * @author Heiko Braun * @date 3/24/11 */ public class LHSNavTree extends Tree implements LHSHighlightEvent.NavItemSelectionHandler { private static final String TREE_ID_ATTRIBUTE = "treeid"; private static final Framework framework = GWT.create(Framework.class); private String treeId; private String category; private LHSNavTreeItem prevNavItem; public LHSNavTree(final String category) { this(DefaultTreeResources.INSTANCE, category); } public LHSNavTree(Tree.Resources resources, final String category) { super(resources); this.treeId = "lhs-nav-tree_" + HTMLPanel.createUniqueId(); this.category = category; addStyleName("stack-section"); /** * actions that reveal content */ addKeyDownHandler(new KeyDownHandler() { public void onKeyDown(KeyDownEvent keyDownEvent) { if (keyDownEvent.getNativeKeyCode() == KeyCodes.KEY_ENTER) { revealContent(false); } } }); addMouseDownHandler(new MouseDownHandler() { public void onMouseDown(MouseDownEvent mouseDownEvent) { Scheduler.get().scheduleDeferred(new Scheduler.ScheduledCommand() { public void execute() { revealContent(true); } }); } }); Scheduler.get().scheduleEntry(new Scheduler.ScheduledCommand() { public void execute() { framework.getEventBus().addHandler(LHSHighlightEvent.TYPE, LHSNavTree.this); } }); /* Allow clicks on lhs titles to open thr tree */ addMouseDownHandler(new MouseDownHandler() { public void onMouseDown(MouseDownEvent event) { EventTarget target = event.getNativeEvent().getEventTarget(); com.google.gwt.dom.client.Element el = Element.as(target); final String title = el.getInnerText(); if (el.getTagName().equalsIgnoreCase("div")) { applyStateChange(new StateChange() { public void applyTo(TreeItem treeItem) { boolean isMatched = title.equals(treeItem.getText()); if (isMatched) { treeItem.setState(!treeItem.getState()); } } }); } } }); } /** * flag the 'active' item and revel content if necessary */ private void revealContent(boolean open) { TreeItem activeItem = getSelectedItem(); if (activeItem instanceof LHSNavTreeItem) { ((LHSNavTreeItem) activeItem).reveal(); } } public String getTreeId() { return treeId; } @Override public void addItem(TreeItem item) { item.getElement().setAttribute(TREE_ID_ATTRIBUTE, treeId); super.addItem(item); } public void onSelectedNavTree(final LHSHighlightEvent event) { if (category.equals(event.getCategory()) || event.getCategory().equals("*")) { applyStateChange(new StateChange() { public void applyTo(TreeItem treeItem) { if (!(treeItem instanceof LHSNavTreeItem)) return; LHSNavTreeItem target = (LHSNavTreeItem) treeItem; String token = treeItem.getElement().hasAttribute("token") ? treeItem.getElement().getAttribute("token") : "not-set"; boolean isSelected = event.getItem().equals(treeItem.getText()) || token.equals(event.getToken()); if (isSelected) { if (prevNavItem != null && !prevNavItem.equals(treeItem)) prevNavItem.setActive(false); prevNavItem = target; openParents(treeItem); target.setActive(true); } else { target.setActive(false); } } }); } } private void openParents(TreeItem treeItem) { TreeItem parentItem = treeItem.getParentItem(); if (parentItem != null) { parentItem.setState(true); openParents(parentItem); } } void applyStateChange(StateChange stateChange) { for (int i = 0; i < getItemCount(); i++) { dfsItem(stateChange, getItem(i)); } } private void dfsItem(StateChange stateChange, TreeItem item) { if (null == item) return; for (int x = 0; x < item.getChildCount(); x++) { dfsItem(stateChange, item.getChild(x)); } stateChange.applyTo(item); } interface StateChange { void applyTo(TreeItem item); } public void expandTopLevel() { for (int i = 0; i < getItemCount(); i++) { TreeItem item = getItem(i); item.setState(true); } } }