启动的服务不起作用

Question

I have and activity that starts an IntentService that is supposed to update the location regularly and post it to Firebase. Somehow it does not work. There is no exception, no error or anything. It just does not do what I want.

Here is my main activity:

public class MainActivity extends AppCompatActivity {

    private Intent mTrackingIntent;

    //UI
    protected Button mStartTrackingButton;
    protected Button mStopTrackingButton;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //Locate the UI widgets
        mStartTrackingButton = (Button) findViewById(R.id.start_button);
        mStopTrackingButton = (Button) findViewById(R.id.stop_button);

        mTrackingIntent = new Intent(this, TrackingService.class);
    }

    public void startButtonHandler(View view) {
        startService(mTrackingIntent);
}
    public void stopButtonHandler(View view) {
        stopService(mTrackingIntent);
    }

Here is TrackingService :

public class TrackingService extends IntentService implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {

private FirebaseAuth mFirebaseAuth;
private FirebaseUser mFirebaseUser;
public static final String SENDER_EMAIL = "*************";
public static final String SENDER_PASSWORD = "******************";
private DatabaseReference mDatabase;
private String mUserId;

private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 10000; //upper bound
public static final long FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS = UPDATE_INTERVAL_IN_MILLISECONDS / 2; //lower bound

private String mLastUpdateTime;
private String mLastUpdateYear;
private String mLastUpdateMonth;
private String mLastUpdateDay;
private static final SimpleDateFormat mYearFormat = new SimpleDateFormat("yyyy");
private static final SimpleDateFormat mMonthFormat = new SimpleDateFormat("MM");
private static final SimpleDateFormat mDayFormat = new SimpleDateFormat("dd");
private static final SimpleDateFormat mTimeFormat = new SimpleDateFormat("HH:mm:ss");
private Location mLastUpdateLocation;

public TrackingService() {
    super("TrackingService");
}

@Override
public void onDestroy() {
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
    super.onDestroy();
}

@Override
protected void onHandleIntent(Intent intent) {

    //Initialize Firebase Auth
    initFirebase();

    //connect to the Google API
    buildGoogleApiClient();

    startLocationUpdates();

}

private void initFirebase() {
    mFirebaseAuth = FirebaseAuth.getInstance();
    mFirebaseUser = mFirebaseAuth.getCurrentUser();
    mDatabase = FirebaseDatabase.getInstance().getReference();

    if (mFirebaseUser == null) {
        //log in to Firebase
        mFirebaseAuth.signInWithEmailAndPassword(SENDER_EMAIL, SENDER_PASSWORD);
        mFirebaseUser = mFirebaseAuth.getCurrentUser();
        mUserId = mFirebaseUser.getUid();
    }
    mUserId = mFirebaseUser.getUid();
}

protected void buildGoogleApiClient() {
    mGoogleApiClient = new GoogleApiClient.Builder(this).addConnectionCallbacks(this).addOnConnectionFailedListener(this).addApi(LocationServices.API).build();
    //Set update interval bounds and accuracy
    createLocationRequest();
    mGoogleApiClient.connect();
}

private void createLocationRequest() {
    mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
    mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}

private void startLocationUpdates() {
    //check if permission to get the location is granted
    if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(
            this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
    }
}

@Override
public void onLocationChanged(Location location) {
    Date updateDate = Calendar.getInstance().getTime();
    mLastUpdateTime = mTimeFormat.format(updateDate);
    mLastUpdateYear = mYearFormat.format(updateDate);
    mLastUpdateMonth = mMonthFormat.format(updateDate);
    mLastUpdateDay = mDayFormat.format(updateDate);
    mLastUpdateLocation = location;

    //post to Firebase
    postToFirebase(location);
}

public void postToFirebase(Location location) {
    mDatabase.child("users").child(mUserId).child(mLastUpdateYear).child(mLastUpdateMonth).child(mLastUpdateDay).child("trackRecords").push().setValue(location);
}

@Override
public void onConnected(@Nullable Bundle bundle) {
    startLocationUpdates();
}

@Override
public void onConnectionSuspended(int i) {
    mGoogleApiClient.connect();
}

@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

}
}

Answer 1

IntentService is not really the right tool for this job. The way IntentService works is this. When an Intent is received from startService(), it will use a background thread to handle the intent (starting in onHandleIntent()), and when that method returns, the IntentService stops itself and shuts down if there are no more intents in its queue.

Instead you probably need to create a custom service that manages its lifecycle so that it performs its background work so that it stays active until it's told to stop.