我尝试在应用程序在后台运行时获取当前位置，因此我使用服务。但是，数据在后台不会改变，服务不起作用。我想知道这个问题。这是应用程序的代码。
MainActivity如下：
public class MainActivity extends Activity {
Button btn_start;
private static final int REQUEST_PERMISSIONS = 100;
boolean boolean_permission;
TextView tv_latitude, tv_longitude, tv_address,tv_area,tv_locality;
SharedPreferences mPref;
SharedPreferences.Editor medit;
Double latitude,longitude;
Geocoder geocoder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn_start = (Button) findViewById(R.id.btn_start);
tv_address = (TextView) findViewById(R.id.tv_address);
tv_latitude = (TextView) findViewById(R.id.tv_latitude);
tv_longitude = (TextView) findViewById(R.id.tv_longitude);
tv_area = (TextView)findViewById(R.id.tv_area);
tv_locality = (TextView)findViewById(R.id.tv_locality);
geocoder = new Geocoder(this, Locale.getDefault());
mPref = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
medit = mPref.edit();
btn_start.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (boolean_permission) {
if (mPref.getString("service", "").matches("")) {
medit.putString("service", "service").commit();
Intent intent = new Intent(getApplicationContext(), GoogleService.class);
startService(intent);
} else {
Toast.makeText(getApplicationContext(), "Service is already running", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(getApplicationContext(), "Please enable the gps", Toast.LENGTH_SHORT).show();
}
}
});
fn_permission();
}
private void fn_permission() {
if ((ContextCompat.checkSelfPermission(getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)) {
if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, android.Manifest.permission.ACCESS_FINE_LOCATION))) {
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION
},
REQUEST_PERMISSIONS);
}
} else {
boolean_permission = true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case REQUEST_PERMISSIONS: {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
boolean_permission = true;
} else {
Toast.makeText(getApplicationContext(), "Please allow the permission", Toast.LENGTH_LONG).show();
}
}
}
}
private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
latitude = Double.valueOf(intent.getStringExtra("latitude"));
longitude = Double.valueOf(intent.getStringExtra("longitude"));
List<Address> addresses = null;
try {
addresses = geocoder.getFromLocation(latitude, longitude, 1);
String cityName = addresses.get(0).getAddressLine(0);
String stateName = addresses.get(0).getAddressLine(1);
String countryName = addresses.get(0).getAddressLine(2);
tv_area.setText(addresses.get(0).getAdminArea());
tv_locality.setText(stateName);
tv_address.setText(countryName);
} catch (IOException e1) {
e1.printStackTrace();
}
tv_latitude.setText(latitude+"");
tv_longitude.setText(longitude+"");
tv_address.getText();
}
};
@Override
protected void onResume() {
super.onResume();
registerReceiver(broadcastReceiver, new IntentFilter(GoogleService.str_receiver));
}
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(broadcastReceiver);
}
}
服务如下：
public class GoogleService extends Service implements LocationListener{
boolean isGPSEnable = false;
boolean isNetworkEnable = false;
double latitude,longitude;
LocationManager locationManager;
Location location;
private Handler mHandler = new Handler();
private Timer mTimer = null;
long notify_interval = 1000;
public static String str_receiver =
"com.findmyelderly.findmyelderly.receiver";
Intent intent;
public GoogleService() {
}
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
mTimer = new Timer();
mTimer.schedule(new TimerTaskToGetLocation(),5,notify_interval);
intent = new Intent(str_receiver);
// fn_getlocation();
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
private void fn_getlocation() {
locationManager = (LocationManager) getApplicationContext().getSystemService(LOCATION_SERVICE);
isGPSEnable = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
isNetworkEnable = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnable && !isNetworkEnable) {
} else {
if (isNetworkEnable) {
location = null;
try {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 1000, 0, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
Log.e("latitude", location.getLatitude() + "");
Log.e("longitude", location.getLongitude() + "");
latitude = location.getLatitude();
longitude = location.getLongitude();
fn_update(location);
}
}
} catch (SecurityException e) {
e.printStackTrace();
}
}
if (isGPSEnable) {
location = null;
try {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
Log.e("latitude", location.getLatitude() + "");
Log.e("longitude", location.getLongitude() + "");
latitude = location.getLatitude();
longitude = location.getLongitude();
fn_update(location);
}
}
} catch (SecurityException e) {
e.printStackTrace();
}
}
}
}
private class TimerTaskToGetLocation extends TimerTask {
@Override
public void run() {
mHandler.post(new Runnable() {
@Override
public void run() {
fn_getlocation();
}
});
}
}
private void fn_update(Location location){
intent.putExtra("latutide",location.getLatitude()+"");
intent.putExtra("longitude",location.getLongitude()+"");
sendBroadcast(intent);
}
}
build.gradle如下
.........
compile 'com.android.support:appcompat-v7:25.0.0'
compile 'com.google.android.gms:play-services-location:10.0.1'
compile 'com.android.support:multidex:1.0.0'
AndroidManifest如下
..........
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
.........
<service android:name=".GoogleService" android:exported="false" android:enabled="true"/>
</application>
</manifest>
我很困惑。
答案 0 :(得分：0)
您可以尝试的一件事是检查手机上应用程序的权限。我发现我的设备（Android版本6.0.1）仅仅添加“uses-permission android：name =”android.permission.ACCESS_FINE_LOCATION“/＆gt;并且 “uses-permission android：name =”android.permission.ACCESS_COARSE_LOCATION“/＆gt;” 在清单中，您必须在设备上手动授予应用程序权限。
要执行此操作，请转到设置＆gt;应用＆gt; 'yourApp'＆gt;权限并在栏上滑动以启用该应用的位置。
我自己对Android应用程序足够新，所以在你的情况下可能会有一个更大的问题我不确定但是还是值得一试！