我正在尝试使用Android中的GPS获取坐标。我已成功获取前景中的位置，但是每当我将应用程序置于背景中时，GPS标志就会消失，并且在背景中时它会停止定位。 我使用了不同版本的android，一些定位位置点（低于8.0），有些则没有（派）。
如何在Pie中保持GPS在后台运行。我尝试了不同的答案，但没有找到解决方法。
我正在使用Service在后台运行应用程序，并使用广播接收器获取坐标。但是我没有在Pie版本中获得积分。
这是我的MainActivity.java
public class MainActivity extends AppCompatActivity {
private LocationManager locationManager;
private LocationListener locationListener;
private double latitude, longitude;
BroadcastReceiver broadcastReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
/*inflating layout*/
riderFirstName = findViewById(R.id.rider_fName);
riderLastName = findViewById(R.id.rider_lName);
riderNote = findViewById(R.id.note);
logout = findViewById(R.id.logout);
if (!runtime_permissions()) {
Intent i = new Intent(getApplicationContext(), GPS_Service.class);
startService(i);
}
}
@Override
protected void onResume() {
super.onResume();
if (broadcastReceiver==null){
broadcastReceiver=new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
double lat = (double) intent.getExtras().get("latitude");
double lng= (double) intent.getExtras().get("longitude");
Log.i("lat", String.valueOf(lat));
Log.i("lang", String.valueOf(lng));
Log.i("lang", String.valueOf(RiderID));
}
};
}
registerReceiver(broadcastReceiver, new IntentFilter("location_update"));
}
@Override
protected void onDestroy() {
super.onDestroy();
if (broadcastReceiver!=null)
unregisterReceiver(broadcastReceiver);
}
private boolean runtime_permissions() {
if (Build.VERSION.SDK_INT >= 23 && ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, 100);
return true;
}
return false;
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == 100) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED && grantResults[1] == PackageManager.PERMISSION_GRANTED) {
Intent i = new Intent(getApplicationContext(), GPS_Service.class);
startService(i);
} else {
runtime_permissions();
}
}
}
}
这是我的服务班
public class GPS_Service extends Service {
PowerManager.WakeLock wakeLock;
private LocationListener listener;
private LocationManager locationManager;
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@SuppressLint("InvalidWakeLockTag")
@Override
public void onCreate() {
listener = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
Intent i = new Intent("location_update");
i.putExtra("latitude", location.getLatitude());
i.putExtra("longitude", location.getLongitude());
sendBroadcast(i);
}
@Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
@Override
public void onProviderEnabled(String s) {
}
@Override
public void onProviderDisabled(String s) {
Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(i);
}
};
locationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
//noinspection MissingPermission
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, CommonObjects.DELAY_LOCATION, 0, listener);
}
@Override
public void onDestroy() {
super.onDestroy();
if(locationManager != null){
//noinspection MissingPermission
locationManager.removeUpdates(listener);
}
}
}
这是清单
<!-- my permissions -->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
答案 0 :(得分：0)
通过使用startForegroundService()而不是startService()，我得到了针对Oreo（8.0）及更高版本的问题的解决方案（在后台获取GPS位置）。
对于实现，我们必须在Manifest中添加Foreground权限，并在Service类中添加startForeground();方法，如下所示：
这是我更新的MianActivity.java代码
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
...
if (!runtime_permissions()) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
{
Intent serviceIntent = new Intent(context, YourService.class);
ContextCompat.startForegroundService(context, serviceIntent );
}
else
{
context.startService(new Intent(context, YourService.class));
}
}
}
更新了我的服务课程
@SuppressLint("InvalidWakeLockTag")
@Override
public void onCreate() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
startMyOwnForeground();
else
startForeground(1, new Notification());
...
}
private void startMyOwnForeground(){
String NOTIFICATION_CHANNEL_ID = "com.example.simpleapp";
String channelName = "My Background Service";
NotificationChannel chan = null;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
chan = new NotificationChannel(NOTIFICATION_CHANNEL_ID, channelName, NotificationManager.IMPORTANCE_NONE);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
chan.setLightColor(Color.BLUE);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
chan.setLockscreenVisibility(Notification.VISIBILITY_PRIVATE);
}
NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
assert manager != null;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
manager.createNotificationChannel(chan);
}
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID);
Notification notification = notificationBuilder.setOngoing(true)
.setContentTitle("App is running in background")
.setPriority(NotificationManager.IMPORTANCE_MIN)
.setCategory(Notification.CATEGORY_SERVICE)
.build();
startForeground(2, notification);
}
更新的清单权限
...
<uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>