GPS Background service 구현하기

앱이 종료가 되더라도 사용자의 GPS 좌표를 계속 받아올 수 있는 백그라운드 서비스를 구현해보자

 

1. Permission (권한) 부여

- AndroidManifest.xml

: permission 4개 추가

( + LocationService.java 파일 생성 후 아래 <service> 태그 추가 )

<manifest xmlns:...>
...
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />

    <application
        ...

        <service
            android:name=".LocationService"
            android:enabled="true"
            android:exported="false" />
    </application>
</manifest>

>> Android 10(API 수준 29) 이상에서 개발자는 런타임 시 백그라운드 위치 정보 엑세스 권한을 요청하기 위해 앱 매니페스트에서 ACCESS_BACKGROUND_LOCATION 권한을 선언해야 합니다.

>> 또한 앱에서 Android 12 이상을 타겟팅하면 ACCESS_FINE_LOCATION 권한만 요청할 수 없습니다. ACCESS_COARSE_LOCATION 권한도 요청해야 하며 단일 런타임 요청에 두 권한을 모두 포함해야 합니다.

 

% 참조 : https://developer.android.com/training/location/permissions?hl=ko (안드로이드 개발문서)

 

2. gradle 추가

- build.gradle (:app)

dependencies {
	...
    
    // implementation('com.google.android.gms:play-services-location:<최신버전>')
    implementation('com.google.android.gms:play-services-location:18.0.0') // 저는 18.0.0 버전입니다.
}

 

3. 레이아웃 생성

- activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/buttonStartLocationUpdates"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/start_location_update"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/buttonStopLocationUpdates"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/stop_location_updates"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/buttonStartLocationUpdates" />

</androidx.constraintlayout.widget.ConstraintLayout>

- strings.xml ( 참고 )

<resources>
    <string name="app_name">Example_GPS</string>
    <string name="start_location_update">Start_Location_Updates</string>
    <string name="stop_location_updates">Stop_Location_Updates</string>
</resources>

 

4. 서비스 클래스 생성

- LocationService.java (생성)

package com.example.example_gps;

import android.Manifest;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.IBinder;
import android.os.Looper;
import android.util.Log;

import androidx.annotation.Nullable;
import androidx.core.app.ActivityCompat;
import androidx.core.app.NotificationCompat;

import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
import com.google.android.gms.location.LocationServices;

public class LocationService extends Service {
    private LocationCallback mLocationCallback = new LocationCallback() {
        @Override
        public void onLocationResult(LocationResult locationResult) {
            super.onLocationResult(locationResult);
            if (locationResult != null && locationResult.getLastLocation() != null) {
                double latitude = locationResult.getLastLocation().getLatitude();
                double longitude = locationResult.getLastLocation().getLongitude();
                Log.v("LOCATION_UPDATE", latitude + ", " + longitude);
            }
        }
    };

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        throw new UnsupportedOperationException("Not yet implemented");
    }

    private void startLocationService() {
        String channelId = "location_notification_channel";
        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        Intent resultIntent = new Intent();
        PendingIntent pendingIntent = PendingIntent.getActivity(getApplicationContext(), 0, resultIntent, PendingIntent.FLAG_UPDATE_CURRENT);
        NotificationCompat.Builder builder = new NotificationCompat.Builder(getApplicationContext(), channelId);
        builder.setSmallIcon(R.mipmap.ic_launcher);
        builder.setContentTitle("Location Service");
        builder.setDefaults(NotificationCompat.DEFAULT_ALL);
        builder.setContentText("Running");
        builder.setContentIntent(pendingIntent);
        builder.setAutoCancel(false);
        builder.setPriority(NotificationCompat.PRIORITY_MAX);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            if (notificationManager != null && notificationManager.getNotificationChannel(channelId) == null) {
                NotificationChannel notificationChannel = new NotificationChannel(channelId, "Location Service", NotificationManager.IMPORTANCE_HIGH);
                notificationChannel.setDescription("This channel is used by location service");
                notificationManager.createNotificationChannel(notificationChannel);
            }
        }

        LocationRequest locationRequest = LocationRequest.create();
        locationRequest.setInterval(4000);
        locationRequest.setFastestInterval(2000);
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            //    ActivityCompat#requestPermissions
            // here to request the missing permissions, and then overriding
            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
            //                                          int[] grantResults)
            // to handle the case where the user grants the permission. See the documentation
            // for ActivityCompat#requestPermissions for more details.
            return;
        }
        LocationServices.getFusedLocationProviderClient(this).requestLocationUpdates(locationRequest, mLocationCallback, Looper.getMainLooper());
        startForeground(Constants.LOCATION_SERVICE_ID, builder.build());
    }

    private void stopLocationService() {
        LocationServices.getFusedLocationProviderClient(this).removeLocationUpdates(mLocationCallback);
        stopForeground(true);
        stopSelf();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if (intent != null) {
            String action = intent.getAction();
            if (action != null) {
                if (action.equals(Constants.ACTION_START_LOCATION_SERVICE)) {
                    startLocationService();
                } else if (action.equals(Constants.ACTION_STOP_LOCATION_SERVICE)) {
                    stopLocationService();
                }
            }
        }
        return super.onStartCommand(intent, flags, startId);
    }
}

 

- Constants.java (생성)

package com.example.example_gps;

public class Constants {
    static final int LOCATION_SERVICE_ID = 175;
    static final String ACTION_START_LOCATION_SERVICE = "startLocationService";
    static final String ACTION_STOP_LOCATION_SERVICE = "stopLocationService";
}

 

 

5. 버튼 동작하기 ( 메인 액티비티 )

- MainActivity.java

package com.example.example_gps;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.Manifest;
import android.app.ActivityManager;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    private static final int REQUEST_CODE_LOCATION_PERMISSION = 1;

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

        findViewById(R.id.buttonStartLocationUpdates).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_CODE_LOCATION_PERMISSION);
                } else {
                    startLocationService();
                }
            }
        });

        findViewById(R.id.buttonStopLocationUpdates).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                stopLocationService();
            }
        });
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == REQUEST_CODE_LOCATION_PERMISSION && grantResults.length > 0) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                startLocationService();
            } else {
                Toast.makeText(this, "Permission denied!", Toast.LENGTH_SHORT).show();
            }
        }
    }

    private boolean isLocationServiceRunning() {
        ActivityManager activityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
        if (activityManager != null) {
            for (ActivityManager.RunningServiceInfo service : activityManager.getRunningServices(Integer.MAX_VALUE)) {
                if (LocationService.class.getName().equals(service.service.getClassName())) {
                    if (service.foreground) {
                        return true;
                    }
                }
            }
            return false;
        }
        return false;
    }

    private void startLocationService() {
        if (!isLocationServiceRunning()) {
            Intent intent = new Intent(getApplicationContext(), LocationService.class);
            intent.setAction(Constants.ACTION_START_LOCATION_SERVICE);
            startService(intent);
            Toast.makeText(this, "Location service started", Toast.LENGTH_SHORT).show();
        }
    }

    private void stopLocationService() {
        if (isLocationServiceRunning()) {
            Intent intent = new Intent(getApplicationContext(), LocationService.class);
            intent.setAction(Constants.ACTION_STOP_LOCATION_SERVICE);
            startService(intent);
            Toast.makeText(this, "Location service stopped", Toast.LENGTH_SHORT).show();
        }
    }
}

 

- 파일 리스트

 

** 그대로 실행시켜서 Logcat을 보면 앱을 꺼도 GPS가 잡히는 것을 볼 수 있다.

 

 

* 중요 ★★★★★
- 안드로이드 11버전은 권한 요청에서 '항상 허용' 부분이 사라졌다. 그래서 백그라운드에서 일시적으로 작동하고 멈춘다. 

- 정상적으로 작동시키려면 사용자가 직접 앱 꾹 눌러서 '앱정보 > 권한 > 위치 > 항상 허용' 체크해줘야한다.

 

 

// https://www.youtube.com/watch?v=4_RK_5bCoOY&t=1095s 참고

 

 

 

끝