HistoryManager.java :  » GWT » gwtuml » com » objetdirect » gwt » umldrawer » client » Java Open Source

/*
 * This file is part of the GWTUML project and was written by Mounier Florian <mounier-dot-florian.at.gmail'dot'com> for Objet Direct
 * <http://wwww.objetdirect.com>
 * 
 * Copyright  2009 Objet Direct Contact: gwtuml@googlegroups.com
 * 
 * GWTUML is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 * 
 * GWTUML 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 Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License along with GWTUML. If not, see <http://www.gnu.org/licenses/>.
 */
package com.objetdirect.gwt.umldrawer.client;

import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DeferredCommand;
import com.google.gwt.user.client.History;
import com.google.gwt.user.client.ui.LayoutPanel;
import com.google.gwt.user.client.ui.Widget;
import com.objetdirect.gwt.umlapi.client.helpers.OptionsManager;

/**
 * Manage the history url and token. 
 * @author Florian Mounier (mounier-dot-florian.at.gmail'dot'com)
 * @author Raphael Brugier (raphael-dot-brugier.at.gmail'dot'com)
 */
public class HistoryManager implements ValueChangeHandler<String> {
  
  public static final String START_PAGE = "Start";
  public static final String ANIMATED_PAGE = "AnimatedDemo";
  public static final String DEMO_PAGE = "Demo";
  public static final String DRAWER_PAGE = "Drawer";
  
  private LayoutPanel appContainer;

  static void upgradeDiagramURL(final String url) {
    String historyToken = DRAWER_PAGE + "?" + OptionsManager.toURL();
    if (!historyToken.endsWith("&")) {
      historyToken += "&";
    }
    historyToken += "diagram64=" + url;
    History.newItem(historyToken, false);
  }
  
  public HistoryManager() {
    History.addValueChangeHandler(this);
  }


  @Override
  public void onValueChange(final ValueChangeEvent<String> event) {
    String historyToken = event.getValue();
    UrlParser urlParser = new UrlParser(historyToken);
    String pageName = urlParser.getPageName();
    
    if (pageName.equals(DRAWER_PAGE)) {
      DrawerContainer drawerContainer = new DrawerContainer(urlParser); 
      changePage(drawerContainer);
      forceDrawerResize(drawerContainer);
    } 
    else if (pageName.equals(START_PAGE)) {
      changePage(new StartPanel());
    } 
    else if (pageName.equals(DEMO_PAGE)) {
      DrawerContainer drawerContainer = new DrawerContainer();
      new Demo(drawerContainer.getUmlCanvas());
      changePage(drawerContainer);
      forceDrawerResize(drawerContainer);
    } 
    else if (pageName.equals(ANIMATED_PAGE)) { // not working
      DrawerContainer drawerContainer = new DrawerContainer();
      new AnimatedDemo(drawerContainer);
      changePage(drawerContainer);
      forceDrawerResize(drawerContainer);
    }
  }
  
  /**
   * Switch the page currently displayed in the container.
   * @param newPage
   */
  private void changePage(Widget newPage)  {
    appContainer.clear();
    appContainer.add(newPage);
  }
  
  /**
   * Render a page from rule on the given container
   * @param container The container where the page is rendered (usually the RootLayoutPanel)
   */
  public void go(LayoutPanel container) {
    appContainer = container;
     if ("".equals(History.getToken())) {
          History.newItem(START_PAGE);
     }
     else {
         History.fireCurrentHistoryState();
     }
  }
  
  /**
   * Add a deferred command to force the drawer resizing.
   */
  private void forceDrawerResize(final DrawerContainer drawerContainer) {
    DeferredCommand.addCommand(new Command() {
      @Override
      public void execute() {
        drawerContainer.onResize();
      }
    });
  }
}