com.google.code.gwt.geolocation.sample.hellogeolocation.client.HelloGeolocation.java Source code

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Here is the source code for com.google.code.gwt.geolocation.sample.hellogeolocation.client.HelloGeolocation.java

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/*
 * Copyright 2010 Bart Guijt and others.
 * 
 * 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.code.gwt.geolocation.sample.hellogeolocation.client;

import com.google.code.gwt.geolocation.client.Coordinates;
import com.google.code.gwt.geolocation.client.Geolocation;
import com.google.code.gwt.geolocation.client.Position;
import com.google.code.gwt.geolocation.client.PositionCallback;
import com.google.code.gwt.geolocation.client.PositionError;
import com.google.code.gwt.geolocation.client.PositionOptions;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.core.client.GWT.UncaughtExceptionHandler;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class HelloGeolocation implements EntryPoint {

    /**
     * This is the entry point method.
     */
    public void onModuleLoad() {
        GWT.setUncaughtExceptionHandler(new UncaughtExceptionHandler() {
            public void onUncaughtException(Throwable e) {
                RootPanel.get().add(new Label("Uncaught exception: " + e));
            }
        });
        final VerticalPanel main = new VerticalPanel();
        RootPanel.get().add(main);

        main.add(new Label("Geolocation provider: " + Geolocation.getProviderName()));
        //main.add(new Label("GWT strongname: " + GWT.getPermutationStrongName()));  // GWT2.0!

        Label l1 = new Label("Obtaining Geolocation...");
        main.add(l1);
        if (!Geolocation.isSupported()) {
            l1.setText("Obtaining Geolocation FAILED! Geolocation API is not supported.");
            return;
        }
        final Geolocation geo = Geolocation.getGeolocation();
        if (geo == null) {
            l1.setText("Obtaining Geolocation FAILED! Object is null.");
            return;
        }
        l1.setText("Obtaining Geolocation DONE!");

        main.add(new Button("Get Location", new ClickHandler() {
            public void onClick(ClickEvent event) {
                obtainPosition(main, geo);
            }
        }));

        obtainPosition(main, geo);
    }

    private void obtainPosition(final VerticalPanel main, Geolocation geo) {
        final Label l2 = new Label("Obtaining position (timeout: 15 sec)...");
        main.add(l2);

        geo.getCurrentPosition(new PositionCallback() {
            public void onFailure(PositionError error) {
                String message = "";
                switch (error.getCode()) {
                case PositionError.UNKNOWN_ERROR:
                    message = "Unknown Error";
                    break;
                case PositionError.PERMISSION_DENIED:
                    message = "Permission Denied";
                    break;
                case PositionError.POSITION_UNAVAILABLE:
                    message = "Position Unavailable";
                    break;
                case PositionError.TIMEOUT:
                    message = "Time-out";
                    break;
                default:
                    message = "Unknown error code.";
                }
                l2.setText("Obtaining position FAILED! Message: '" + error.getMessage() + "', code: "
                        + error.getCode() + " (" + message + ")");
            }

            public void onSuccess(Position position) {
                l2.setText("Obtaining position DONE - acquired at " + position.getTimestamp());
                Coordinates c = position.getCoords();
                main.add(new Label("lat, lon: " + c.getLatitude() + ", " + c.getLongitude()));
                main.add(new Label("Accuracy (in meters): " + c.getAccuracy()));
                main.add(new Label("Altitude: " + (c.hasAltitude() ? c.getAltitude() : "[no value]")));
                main.add(new Label("Altitude accuracy (in meters): "
                        + (c.hasAltitudeAccuracy() ? c.getAltitudeAccuracy() : "[no value]")));
                main.add(new Label("Heading: " + (c.hasHeading() ? c.getHeading() : "[no value]")));
                main.add(new Label("Speed: " + (c.hasSpeed() ? c.getSpeed() : "[no value]")));
            }
        }, PositionOptions.getPositionOptions(false, 15000, 30000));
    }
}