com.nitrous.gwt.earth.client.demo.ClosingBalloonsDemo.java Source code

Introduction

Here is the source code for com.nitrous.gwt.earth.client.demo.ClosingBalloonsDemo.java

Source

/*
 * Copyright 2012 Nick Kerr
 *
 *   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.nitrous.gwt.earth.client.demo;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.dom.client.Style.Unit;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DockLayoutPanel;
import com.google.gwt.user.client.ui.HasHorizontalAlignment;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.RootLayoutPanel;
import com.nitrous.gwt.earth.client.api.GEHtmlStringBalloon;
import com.nitrous.gwt.earth.client.api.GELayerId;
import com.nitrous.gwt.earth.client.api.GEPlugin;
import com.nitrous.gwt.earth.client.api.GEPluginReadyListener;
import com.nitrous.gwt.earth.client.api.GEVisibility;
import com.nitrous.gwt.earth.client.api.GoogleEarth;
import com.nitrous.gwt.earth.client.api.GoogleEarthWidget;
import com.nitrous.gwt.earth.client.api.KmlAltitudeMode;
import com.nitrous.gwt.earth.client.api.KmlLookAt;
import com.nitrous.gwt.earth.client.api.KmlPlacemark;
import com.nitrous.gwt.earth.client.api.KmlPoint;

/**
 * A GWT implementation of the demo found <a href="http://code.google.com/apis/ajax/playground/?exp=earth#closing_balloons">here</a>.
 * 
 * @author nick
 * 
 */
public class ClosingBalloonsDemo implements EntryPoint {

    private GoogleEarthWidget earth;
    private KmlPlacemark placemark;

    public void onModuleLoad() {
        // Load the Earth API
        GoogleEarth.loadApi(new Runnable() {
            @Override
            public void run() {
                // start the application
                onApiLoaded();
            }
        });
    }

    /**
     * The Google earth API has loaded, start the application
     */
    private void onApiLoaded() {
        // construct the UI widget
        earth = new GoogleEarthWidget();

        // register a listener to be notified when the earth plug-in has loaded
        earth.addPluginReadyListener(new GEPluginReadyListener() {
            public void pluginReady(GEPlugin ge) {
                // show map content once the plugin has loaded
                loadMapContent();
            }

            public void pluginInitFailure() {
                // failure!
                Window.alert("Failed to initialize Google Earth Plug-in");
            }
        });

        Button showButton = new Button("Show a balloon!");
        showButton.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                GEPlugin ge = earth.getGEPlugin();
                GEHtmlStringBalloon balloon = ge.createHtmlStringBalloon("");
                balloon.setFeature(placemark); // optional
                balloon.setMaxWidth(300);

                // Google logo.
                balloon.setContentString("<img src=\"http://www.google.com/intl/en_ALL/images/logo.gif\"><br>"
                        + "<font size=20>Earth Plugin</font><br><font size=-2>sample info " + "window</font>");
                ge.setBalloon(balloon);
            }
        });
        Button closeButton = new Button("Close the balloon!");
        closeButton.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                // hide the balloon
                earth.getGEPlugin().setBalloon(null);
            }
        });

        HorizontalPanel buttons = new HorizontalPanel();
        buttons.add(showButton);
        buttons.add(closeButton);

        HorizontalPanel topPanel = new HorizontalPanel();
        topPanel.setWidth("100%");
        topPanel.setHorizontalAlignment(HasHorizontalAlignment.ALIGN_CENTER);
        topPanel.add(buttons);

        DockLayoutPanel layout = new DockLayoutPanel(Unit.PX);
        layout.addNorth(topPanel, 40D);
        layout.add(earth);
        RootLayoutPanel.get().add(layout);

        // begin loading the Google Earth Plug-in
        earth.init();
    }

    /**
     * Display content on the map
     */
    private void loadMapContent() {
        // The GEPlugin is the core class and is a great place to start browsing
        // the API
        GEPlugin ge = earth.getGEPlugin();
        ge.getWindow().setVisibility(true);

        // add a navigation control
        ge.getNavigationControl().setVisibility(GEVisibility.VISIBILITY_AUTO);

        // add some layers
        ge.enableLayer(GELayerId.LAYER_BORDERS, true);
        ge.enableLayer(GELayerId.LAYER_ROADS, true);

        // create the placemark
        placemark = ge.createPlacemark("");

        KmlPoint point = ge.createPoint("");
        point.setLatitude(37);
        point.setLongitude(-122);
        placemark.setGeometry(point);

        // add the placemark to the earth DOM
        ge.getFeatures().appendChild(placemark);

        // look at the placemark we created
        KmlLookAt la = ge.createLookAt("");
        la.set(37, -122, 0, // altitude
                KmlAltitudeMode.ALTITUDE_RELATIVE_TO_GROUND, 0, // heading
                0, // straight-down tilt
                5000 // range (inverse of zoom)
        );
        ge.getView().setAbstractView(la);
    }

}