com.google.gwt.maps.sample.hellomaps.client.StreetviewDemo.java Source code

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Here is the source code for com.google.gwt.maps.sample.hellomaps.client.StreetviewDemo.java

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/*
 * Copyright 2010 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.maps.sample.hellomaps.client;

import com.google.gwt.maps.client.MapWidget;
import com.google.gwt.maps.client.event.StreetviewInitializedHandler;
import com.google.gwt.maps.client.event.MapClickHandler;
import com.google.gwt.maps.client.event.StreetviewPitchChangedHandler;
import com.google.gwt.maps.client.event.StreetviewYawChangedHandler;
import com.google.gwt.maps.client.event.StreetviewZoomChangedHandler;
import com.google.gwt.maps.client.geom.LatLng;
import com.google.gwt.maps.client.overlay.Polygon;
import com.google.gwt.maps.client.streetview.LatLngStreetviewCallback;
import com.google.gwt.maps.client.streetview.StreetviewPanoramaOptions;
import com.google.gwt.maps.client.streetview.StreetviewPanoramaWidget;
import com.google.gwt.maps.client.streetview.Pov;
import com.google.gwt.maps.client.streetview.StreetviewClient;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * This demo shows how to construct a {@link StreetviewPanoramaWidget}, handle
 * Street View events and perform a panorama lookups.
 */
public class StreetviewDemo extends MapsDemo {
    private static HTML descHTML = null;
    private static final String descString = "<p>Creates a Street View Panorama "
            + "and a Map to demonstrate dispatching event between these two objects.</p>"
            + "<p>Expect to see a polygon object that represents you Street View point of"
            + " view on a map. Click on a map to change your location in Street View.</p>";

    public static MapsDemoInfo init() {
        return new MapsDemoInfo() {
            @Override
            public MapsDemo createInstance() {
                return new StreetviewDemo();
            }

            @Override
            public HTML getDescriptionHTML() {
                if (descHTML == null) {
                    descHTML = new HTML(descString);
                }
                return descHTML;
            }

            @Override
            public String getName() {
                return "Streetview Test";
            }
        };
    }

    private final VerticalPanel panel;
    private final MapWidget map;
    private final StreetviewPanoramaWidget panorama;
    private final StreetviewClient svClient;
    private final LatLng tenthStreet = LatLng.newInstance(33.78148, -84.38713);

    private LatLng currentLatLng = tenthStreet;
    private Pov currentPov = Pov.newInstance();
    private Polygon viewPolygon;

    public StreetviewDemo() {
        StreetviewPanoramaOptions options = StreetviewPanoramaOptions.newInstance();
        options.setLatLng(tenthStreet);
        svClient = new StreetviewClient();
        panorama = new StreetviewPanoramaWidget(options);
        panorama.setSize("500px", "300px");

        map = new MapWidget(tenthStreet, 16);
        map.setSize("500px", "300px");
        map.addMapClickHandler(new MapClickHandler() {
            public void onClick(MapClickEvent event) {
                LatLng point = event.getLatLng() == null ? event.getOverlayLatLng() : event.getLatLng();
                if (point != null) {
                    svClient.getNearestPanoramaLatLng(point, new LatLngStreetviewCallback() {
                        @Override
                        public void onFailure() {
                        }

                        @Override
                        public void onSuccess(LatLng point) {
                            panorama.setLocationAndPov(point, Pov.newInstance());
                        }
                    });
                }
            }
        });

        panorama.addInitializedHandler(new StreetviewInitializedHandler() {
            public void onInitialized(StreetviewInitializedEvent event) {
                currentLatLng = event.getLocation().getLatLng();
                currentPov = event.getLocation().getPov();
                map.setCenter(currentLatLng);
                updatePolyline();
            }
        });

        panorama.addPitchChangedHandler(new StreetviewPitchChangedHandler() {
            public void onPitchChanged(StreetviewPitchChangedEvent event) {
                currentPov.setPitch(event.getPitch());
                updatePolyline();
            }
        });

        panorama.addYawChangedHandler(new StreetviewYawChangedHandler() {
            public void onYawChanged(StreetviewYawChangedEvent event) {
                currentPov.setYaw(event.getYaw());
                updatePolyline();
            }
        });

        panorama.addZoomChangedHandler(new StreetviewZoomChangedHandler() {
            public void onZoomChanged(StreetviewZoomChangedEvent event) {
                currentPov.setZoom(event.getZoom());
                updatePolyline();
            }
        });

        panel = new VerticalPanel();
        panel.add(panorama);
        panel.add(map);
        initWidget(panel);
    }

    private void updatePolyline() {
        if (viewPolygon != null) {
            map.removeOverlay(viewPolygon);
        }

        // Some simple math to calculate viewPolygon

        double yaw = currentPov.getYaw();
        double distanceFactor = Math.cos(Math.toRadians(currentPov.getPitch())) * 0.0015 + 0.0005;
        double zoomFactor = currentPov.getZoom() * 0.7 + 1;

        LatLng[] points = new LatLng[11];
        points[0] = points[10] = currentLatLng;
        for (int i = 1; i < 10; i++) {
            double angle = Math.toRadians(yaw + (i - 5) * 7d / zoomFactor);
            points[i] = LatLng.newInstance(currentLatLng.getLatitude() + Math.cos(angle) * distanceFactor,
                    currentLatLng.getLongitude() + Math.sin(angle) * distanceFactor);
        }

        viewPolygon = new Polygon(points, "blue", 1, 0.5, "blue", 0.15);
        map.addOverlay(viewPolygon);
    }
}