gpxservice.java

Android从入门到精通

package com.androidbook.services;

import java.util.Date;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;

public class GPXService extends Service {
    private static final int GPS_NOTIFY = 0x2001;

    private static final String DEBUG_TAG = "GPXService";
    
    public static final String EXTRA_UPDATE_RATE = "update-rate";
    public static final String GPX_SERVICE = "com.androidbook.GPXService.SERVICE";
        
    private LocationManager location = null;
    private NotificationManager notifier = null;
    private int updateRate = -1;
    @Override
    public void onCreate() {
        super.onCreate();
        
        location = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        notifier = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    }

    @Override
    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
        updateRate = intent.getIntExtra(EXTRA_UPDATE_RATE, -1);
        if (updateRate == -1) {
            updateRate = 60000;
        }
        
        Criteria criteria = new Criteria();
        criteria.setAccuracy(Criteria.NO_REQUIREMENT);
        criteria.setPowerRequirement(Criteria.POWER_LOW);
        
        location = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        
        String best = location.getBestProvider(criteria, true);
        
        location.requestLocationUpdates(best, updateRate, 0, trackListener);
        
        // notify that we've started up
        Notification notify = new Notification(android.R.drawable.stat_notify_more, "GPS Tracking", System.currentTimeMillis());
        notify.flags |= Notification.FLAG_AUTO_CANCEL;
        Intent toLaunch = new Intent(getApplicationContext(), ServiceControl.class);
        PendingIntent intentBack = PendingIntent.getActivity(getApplicationContext(), 0, toLaunch, 0);
        
        notify.setLatestEventInfo(getApplicationContext(), "GPS Tracking", "Tracking start at "+updateRate+"ms intervals with ["+best+"] as the provider.", intentBack);
        notifier.notify(GPS_NOTIFY, notify);
    }

    @Override
    public void onDestroy() {
        if (location != null) {
            location.removeUpdates(trackListener);
            location = null;
        }
        
        // notify that we've stopped
        Notification notify = new Notification(android.R.drawable.stat_notify_more, "GPS Tracking", System.currentTimeMillis());
        notify.flags |= Notification.FLAG_AUTO_CANCEL;
        Intent toLaunch = new Intent(getApplicationContext(), ServiceControl.class);
        PendingIntent intentBack = PendingIntent.getActivity(getApplicationContext(), 0, toLaunch, 0);
        
        notify.setLatestEventInfo(getApplicationContext(), "GPS Tracking", "Tracking stopped", intentBack);
        notifier.notify(GPS_NOTIFY, notify);
        
        super.onDestroy();
    }

    @Override
    public IBinder onBind(Intent intent) {
        // we only have one, so no need to check the intent
        return mRemoteInterfaceBinder;
    }
    
    // our remote interface
    private final IRemoteInterface.Stub mRemoteInterfaceBinder = new IRemoteInterface.Stub() {
        public Location getLastLocation() {
            Log.v("interface", "getLastLocation() called");
            return lastLocation;
        }
        
        public GPXPoint getGPXPoint() {
            if (lastLocation == null) {
                return null;
            } else {
                Log.v("interface", "getGPXPoint() called");
                GPXPoint point = new GPXPoint();
                point.elevation = lastLocation.getAltitude();

                point.latitude = (int) (lastLocation.getLatitude() * 1E6);
                point.longitude = (int) (lastLocation.getLongitude() * 1E6);
                point.timestamp = new Date(lastLocation.getTime());
                return point;
            }
        }
  
    };
    
    private Location firstLocation = null;
    private Location lastLocation = null;
    private long lastTime = -1;
    private long firstTime = -1;
    private LocationListener trackListener = new LocationListener () {



        public void onLocationChanged(Location location) {
            long thisTime = System.currentTimeMillis();
            long diffTime = thisTime - lastTime;
            Log.v(DEBUG_TAG, "diffTime == " + diffTime + ", updateRate = " + updateRate);
            if (diffTime < updateRate) {
                // it hasn't been long enough yet
                return;
            }
            lastTime = thisTime;
            String locInfo = String.format("Current loc = (%f, %f) @ (%.1f meters up)", location.getLatitude(), location.getLongitude(), location.getAltitude());
            if (lastLocation != null) {
                float distance = location.distanceTo(lastLocation);
                locInfo += String.format("\n Distance from last = %.1f meters", distance);
                float lastSpeed = distance / diffTime;
                locInfo += String.format("\n\tSpeed: %.1fm/s", lastSpeed);
                if (location.hasSpeed())  {
                    float gpsSpeed = location.getSpeed();
                    locInfo += String.format(" (or %.1fm/s)", lastSpeed, gpsSpeed);
                } else {
                    
                }
            
            }
            
            if (firstLocation != null && firstTime != -1) {
                float overallDistance = location.distanceTo(firstLocation);
                float overallSpeed = overallDistance / (thisTime - firstTime);
                locInfo += String.format("\n\tOverall speed: %.1fm/s over %.1f meters", overallSpeed, overallDistance);
            }
            
            lastLocation = location;
            if (firstLocation == null) {
                firstLocation = location;
                firstTime = thisTime;
            }

            Toast.makeText(getApplicationContext(), locInfo, Toast.LENGTH_LONG).show();
            Log.v(DEBUG_TAG, "Test time");
        }

        public void onProviderDisabled(String provider) {
            Log.v(DEBUG_TAG, "Provider disabled "+ provider);

        }

        public void onProviderEnabled(String provider) {
            Log.v(DEBUG_TAG, "Provider enabled "+ provider);
            
        }

        public void onStatusChanged(String provider, int status, Bundle extras) {
            
        }
        
    };

}