/*
* 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.examples;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.user.client.History;
import com.google.gwt.user.client.ui.Hyperlink;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.VerticalPanel;
public class HistoryExample implements EntryPoint, ValueChangeHandler<String> {
private Label lbl = new Label();
public void onModuleLoad() {
// Create three hyperlinks that change the application's history.
Hyperlink link0 = new Hyperlink("link to foo", "foo");
Hyperlink link1 = new Hyperlink("link to bar", "bar");
Hyperlink link2 = new Hyperlink("link to baz", "baz");
// If the application starts with no history token, redirect to a new
// 'baz' state.
String initToken = History.getToken();
if (initToken.length() == 0) {
History.newItem("baz");
}
// Add widgets to the root panel.
VerticalPanel panel = new VerticalPanel();
panel.add(lbl);
panel.add(link0);
panel.add(link1);
panel.add(link2);
RootPanel.get().add(panel);
// Add history listener
History.addValueChangeHandler(this);
// Now that we've setup our listener, fire the initial history state.
History.fireCurrentHistoryState();
}
public void onValueChange(ValueChangeEvent<String> event) {
// This method is called whenever the application's history changes. Set
// the label to reflect the current history token.
lbl.setText("The current history token is: " + event.getValue());
}
}