我已经写了一个后台服务，根据我在AlarmManager中设置的时间限制，将纬度，经度和其他一些细节插入我的sqlite数据库。 我使用GoogleApiClient来计算纬度和经度，但我遇到了一些问题。
问题
当我在没有网的情况下外出旅行时，纬度和经度不会定期更新。数据会定期插入我的sqlite，但经过半小时后纬度和经度保持不变，但我旅行的时间约为10公里。 我希望在旅行时像自动更新一样改变纬度和经度。
我想知道FusedLocationApi是否正确计算纬度经度，即使我没有连接到互联网，如果是，那么我需要一些建议来改进我尝试过的代码。
我试过的代码。
AlarmManagerService.java
public class AlarmManagerService extends Service implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener, LocationListener {
private static final String TAG = "AlarmManagerService";
AlarmReceiver alarmReceiver;
DriverDbHelper driverDbHelper;
Handler handler;
private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 1000;
private Location mLastLocation;
// Google client to interact with Google API
private GoogleApiClient mGoogleApiClient;
// boolean flag to toggle periodic location updates
private boolean mRequestingLocationUpdates = false;
private LocationRequest mLocationRequest;
// Location updates intervals in sec
private static int UPDATE_INTERVAL = 120000; // 2 mins
private static int FATEST_INTERVAL = 60000; // 1 min
private static int DISPLACEMENT = 10; // 10 meters
public Activity activity;
protected String mLastUpdateTime;
String areaName0, areaName1, areaName2, areaName3, fullAreaName,
sessionMobileNo, sessionDriverName, sessionDID, sessiondriverUserId,
date, time, dateTime, doc, trac_transId;
double latitude, longitude;
PowerManager.WakeLock mWakeLock;
SessionManager session;
ConnectionDetector cd;
Boolean isInternet = false;
String sync_no = "No";
String sync_yes = "Yes";
public AlarmManagerService() {
alarmReceiver = new AlarmReceiver();
driverDbHelper = new DriverDbHelper(this);
cd = new ConnectionDetector(this);
}
public void setActivity(Activity activity) {
this.activity = activity;
}
@Override
public void onCreate() {
super.onCreate();
try {
driverDbHelper.open(AlarmManagerService.this);
} catch (Exception e) {
e.printStackTrace();
}
Log.d("Service created", "Alarm Service Created");
// First we need to check availability of play services
if (checkPlayServices()) {
// Building the GoogleApi client
buildGoogleApiClient();
createLocationRequest();
}
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
PowerManager mgr = (PowerManager)
getSystemService(Context.POWER_SERVICE);
if (this.mWakeLock == null) {
this.mWakeLock = mgr.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
"MyWakeLock");
}
if (!this.mWakeLock.isHeld()) {
this.mWakeLock.acquire();
}
if (mGoogleApiClient != null) {
mGoogleApiClient.connect();
}
Log.d("Service started", "Alarm Service Started");
handler = new Handler(Looper.myLooper());
handler.post(new Runnable() {
@Override
public void run() {
postDatabaseDetails();
}
});
return START_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onDestroy() {
super.onDestroy();
Log.d("Service started", "Alarm Service Destroyed");
if (mGoogleApiClient.isConnected()) {
stopLocationUpdates();
mGoogleApiClient.disconnect();
}
if (this.mWakeLock != null) {
this.mWakeLock.release();
this.mWakeLock = null;
}
}
private void displayLocation() {
if (mLastLocation != null) {
latitude = mLastLocation.getLatitude();
longitude = mLastLocation.getLongitude();
List<Address> addressList = null;
try {
Geocoder gcd = new Geocoder(getBaseContext(),
Locale.getDefault());
addressList = gcd.getFromLocation(mLastLocation.getLatitude(),
mLastLocation.getLongitude(), 1);
if (addressList != null && addressList.size() > 0) {
Address address = addressList.get(0);
areaName0 = address.getLocality(); // city name
areaName1 = address.getSubLocality();
areaName2 = address.getAdminArea();// statename
//areaName3 = address.getFeatureName(); plot no
//areaName3 = address.getCountryCode();// IN
areaName3 = address.getThoroughfare();
fullAreaName = areaName3 + "\n" + areaName1 + "\n" +
areaName0 + "," + areaName2;
} else {
Log.i("Location ", "Location null");
}
} catch (IOException e1) {
Log.e("HomePage", "IO Exception in getFromLocation()");
e1.printStackTrace();
} catch (IllegalArgumentException e2) {
// Error message to post in the log
String errorString = "Illegal arguments " +
Double.toString(mLastLocation.getLatitude()) + " , " +
Double.toString(mLastLocation.getLongitude()) +
" passed to address service";
Log.e("HomePage", errorString);
e2.printStackTrace();
}
}
}
/**
* Creating google api client object
*/
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API).build();
}
/**
* Creating location request object
*/
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL);
//mLocationRequest.setFastestInterval(FATEST_INTERVAL);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setSmallestDisplacement(DISPLACEMENT);
}
/**
* Method to verify google play services on the device
*/
private boolean checkPlayServices() {
int resultCode = GooglePlayServicesUtil
.isGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.SUCCESS) {
if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
GooglePlayServicesUtil.getErrorDialog(resultCode, activity,
PLAY_SERVICES_RESOLUTION_REQUEST).show();
} else {
Log.i("Google play services", "Device not supported");
activity.finish();
}
return false;
}
return true;
}
/**
* Starting the location updates
*/
protected void startLocationUpdates() {
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
/**
* Stopping location updates
*/
protected void stopLocationUpdates() {
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient, this);
}
@Override
public void onConnected(Bundle bundle) {
// Once connected with google api, get the location
//displayLocation();
if (mRequestingLocationUpdates) {
startLocationUpdates();
}
if (mLastLocation == null) {
mLastLocation =
LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
displayLocation();
}
}
@Override
public void onConnectionSuspended(int i) {
mGoogleApiClient.connect();
}
@Override
public void onLocationChanged(Location location) {
// Assign the new location
mLastLocation = location;
mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
Log.d("Location changed ", "Location changed " + mLastLocation);
Log.d("Last updated time", "Last updated location " + mLastUpdateTime);
// Displaying the new location on UI
displayLocation();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = "
+ connectionResult.getErrorCode());
}
public void postDatabaseDetails() {
session = new SessionManager(getApplicationContext());
HashMap<String, String> user = session.getUserDetails();
sessionMobileNo = user.get(SessionManager.KEY_MOBILENO);
sessionDriverName = user.get(SessionManager.KEY_NAME);
sessionDID = user.get(SessionManager.KEY_DEVICEID);
sessiondriverUserId = user.get(SessionManager.KEY_DRIVERUSERID);
Calendar in = Calendar.getInstance();
Date dt = new Date();
in.setTimeZone(TimeZone.getTimeZone("Asia/Kolkata"));
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat stf = new SimpleDateFormat("HH:mm:ss");
date = sdf.format(dt);
time = stf.format(dt);
String timeval = time.toString();
String dateval = date.toString();
dateTime = date.toString() + " " + time.toString();
doc = sessionDID + "" + dateTime;
isInternet = cd.isConnectingToInternet();
if (isInternet) {
long id = driverDbHelper.insertDriverDetails(doc, sessionDID,
sessiondriverUserId, latitude, longitude,
fullAreaName, dateTime, "DEMO", sync_no, dateval, timeval);
postDriverDetails();
Log.d("GPS", "Service started after 2 mins with internet");
} else {
Log.d("Internet status", "No internet available for service");
long id = driverDbHelper.insertDriverDetails(doc, sessionDID,
sessiondriverUserId, latitude, longitude,
"NA", dateTime, "DEMO", sync_no, dateval, timeval);
Log.d("GPS", "Service started after 2 mins without internet");
}
}
我从活动HomePage.java调用此服务，但是从哪里调用下面的代码，从onStart（）或在setContentView（R.layout.home）之后？
try {
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.MINUTE, 2);
AlarmManager am = (AlarmManager)
getSystemService(Context.ALARM_SERVICE);
Intent i = new Intent(Home_Page.this, AlarmManagerService.class);
PendingIntent pi = PendingIntent.getService(Home_Page.this, 0, i,0);
am.setInexactRepeating(AlarmManager.RTC_WAKEUP,
calendar.getTimeInMillis(), EXEC_INTERVAL, pi);
} catch (Exception e) {
e.printStackTrace();
}
我希望我能得到一些改进上述服务代码的建议，因为我希望它能在后台平稳运行，定期更新纬度和经度。