我正在尝试在我的应用程序中使用FusedLocationAPI获取当前位置。它在android API＆gt; 23和＆lt; 23中都可以正常工作。问题是如果未启用GPS，应用程序会提示用户启用GPS，之后该位置将返回null。但是在重新启动应用程序时，它的工作正常。如果GPS没有关闭，应用程序工作正常。有没有什么方法可以让应用程序在获取位置之前等待启用GPS？下面我发布我的代码。请看看。
在onCreate（）中：
manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
statusOfGPS = manager.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (!statusOfGPS) {
displayPromptForEnablingGPS(this);
}
Log.d("permipart", "before");
if(CheckingPermissionIsEnabledOrNot())
{
Toast.makeText(MainActivity.this, "All Permissions Granted Successfully", Toast.LENGTH_LONG).show();
}
else {
RequestMultiplePermission();
}
if(Build.VERSION.SDK_INT<= 23)
{
buildGoogleApiClient();
if (!mGoogleApiClient.isConnected()) {
mGoogleApiClient.connect();
}
}
Log.d("permipart", "out");
其他方法：
@Override
public void onLocationChanged(Location location) {
Log.d("onconnectedlocchange","called");
if (location != null) {
lat = location.getLatitude();
lon = location.getLongitude();
if (!String.valueOf(lat).equals("0.0"))
{
latitudeVal = location.getLatitude();
longitudeVal = location.getLongitude();
Log.e("Lat and Lng", String.valueOf(latitudeVal) + longitudeVal);
}
}
}
@Override
public void onConnected(@Nullable Bundle bundle) {
if(CheckingPermissionIsEnabledOrNot())
{
Toast.makeText(MainActivity.this, "All Permissions Granted Successfully", Toast.LENGTH_LONG).show();
}
// If, If permission is not enabled then else condition will execute.
else {
//Calling method to enable permission.
RequestMultiplePermission();
}
Log.d("onconnected","called");
mLocationRequest = LocationRequest.create();
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
// Update location every second
if (ActivityCompat.checkSelfPermission(this, ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
}
else
{
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
lat = mLastLocation.getLatitude();
lon = mLastLocation.getLongitude();
if (!String.valueOf(lat).equals("0.0")){
latitudeVal = mLastLocation.getLatitude();
longitudeVal = mLastLocation.getLongitude();
Log.e("Lat and Lng", String.valueOf(latitudeVal)+ longitudeVal);
}
}
}
}
@Override
public void onConnectionSuspended(int i) {
}
synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
public void displayPromptForEnablingGPS(final Activity activity) {
final android.support.v7.app.AlertDialog.Builder builder = new android.support.v7.app.AlertDialog.Builder(activity);
final String action = Settings.ACTION_LOCATION_SOURCE_SETTINGS;
final String message = "Do you want open GPS setting?";
builder.setMessage(message)
.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface d, int id) {
activity.startActivity(new Intent(action));
d.dismiss();
}
})
.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface d, int id) {
d.cancel();
}
});
builder.create().show();
}
String[] permissions = new String[]{ACCESS_FINE_LOCATION,
ACCESS_COARSE_LOCATION, READ_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE };
//Permission function starts from here
private void RequestMultiplePermission() {
// Creating String Array with Permissions.
Log.d("permipart", "RequestMultiplePermission");
ActivityCompat.requestPermissions(MainActivity.this, new String[]
{
READ_EXTERNAL_STORAGE,
WRITE_EXTERNAL_STORAGE,
ACCESS_FINE_LOCATION,
ACCESS_COARSE_LOCATION
}, RequestPermissionCode);
}
private boolean checkPermission() {
int result;
List<String> listPermissionsNeeded = new ArrayList<>();
for (String p:permissions) {
result = ContextCompat.checkSelfPermission(this,p);
if (result != PackageManager.PERMISSION_GRANTED) {
listPermissionsNeeded.add(p);
}
}
if (!listPermissionsNeeded.isEmpty()) {
ActivityCompat.requestPermissions(this, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]),10 );
Log.d("permissionissue","no");
return false;
}
Log.d("permissionissue","yes");
return true;
}
@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
Log.d("permipart", "onRequestPermissionsResult");
switch (requestCode) {
case RequestPermissionCode:
if (grantResults.length > 0) {
boolean CameraPermission = grantResults[0] == PackageManager.PERMISSION_GRANTED;
boolean RecordAudioPermission = grantResults[1] == PackageManager.PERMISSION_GRANTED;
boolean SendSMSPermission = grantResults[2] == PackageManager.PERMISSION_GRANTED;
boolean GetAccountsPermission = grantResults[3] == PackageManager.PERMISSION_GRANTED;
if (CameraPermission && RecordAudioPermission && SendSMSPermission && GetAccountsPermission) {
Log.d("permipart", "done");
buildGoogleApiClient();
Toast.makeText(MainActivity.this, "Permission Granted", Toast.LENGTH_LONG).show();
if (!mGoogleApiClient.isConnected()) {
mGoogleApiClient.connect();
}
}
else {
Toast.makeText(MainActivity.this,"Permission Denied",Toast.LENGTH_LONG).show();
}
}
break;
}
}
/**
* Checking permission is enabled or not using function starts from here.
*
*/
public boolean CheckingPermissionIsEnabledOrNot() {
int FirstPermissionResult = ContextCompat.checkSelfPermission(getApplicationContext(), READ_EXTERNAL_STORAGE);
int SecondPermissionResult = ContextCompat.checkSelfPermission(getApplicationContext(), WRITE_EXTERNAL_STORAGE);
int ThirdPermissionResult = ContextCompat.checkSelfPermission(getApplicationContext(), ACCESS_FINE_LOCATION);
int ForthPermissionResult = ContextCompat.checkSelfPermission(getApplicationContext(), ACCESS_COARSE_LOCATION);
return FirstPermissionResult == PackageManager.PERMISSION_GRANTED &&
SecondPermissionResult == PackageManager.PERMISSION_GRANTED &&
ThirdPermissionResult == PackageManager.PERMISSION_GRANTED &&
ForthPermissionResult == PackageManager.PERMISSION_GRANTED ;
}
答案 0 :(得分：2)
你需要接收这样的GPS状态广播：
public class GpsLocationReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().matches("android.location.PROVIDERS_CHANGED")) {
// here you can get the location or start a service to get it.
// example
// Intent getLocationService = new Intent(context,YourService.class);
// context.startService(getLocationService);
}
}
}
根据下面的评论 在你的代码中使用它
manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if(manager.isProviderEnabled( LocationManager.GPS_PROVIDER)){
// it is enabled
}else{
// it is not
}
答案 1 :(得分：1)
使用我的代码，如果关闭，它会要求用户打开GPS。在GPS打开之前，它永远不会返回任何东西。
注意：在将其用于marshmallow及以上手机之前，您必须获得位置许可。
试试这个：
@SuppressWarnings("MissingPermission")
public class LocationFinder implements LocationListener, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
public static final String TAG = "LocationFinder";
private static final String BROADCAST_GPS_REQ = "LocationFinder.GPS_REQ";
private static final String KEY_GPS_REQ = "key.gps.req";
private static final int GPS_REQUEST = 2301;
private Activity activity;
private FinderType finderType;
private GoogleApiClient googleApiClient;
private LocationRequest locationRequest;
private long updateInterval;
private long fastestInterval;
private GpsRequestListener gpsRequestListener;
private LocationUpdateListener locationUpdateListener;
public LocationFinder(Activity activity, FinderType finderType) {
this.activity = activity;
this.finderType = finderType;
}
private void connectGoogleApiClient() {
googleApiClient = new GoogleApiClient.Builder(activity)
.addApi(LocationServices.API).addConnectionCallbacks(this)
.addOnConnectionFailedListener(this).build();
googleApiClient.connect();
}
private void createLocationRequest() {
locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(updateInterval);
locationRequest.setFastestInterval(fastestInterval);
}
private BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
int intExtra = intent.getIntExtra(KEY_GPS_REQ, 0);
switch (intExtra) {
case Activity.RESULT_OK:
try {
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, LocationFinder.this);
} catch (Exception e) {
e.printStackTrace();
}
gpsRequestListener.gpsTurnedOn();
break;
case Activity.RESULT_CANCELED:
gpsRequestListener.gpsNotTurnedOn();
}
}
};
public void gpsRequestCallback(GpsRequestListener gpsRequestListener) {
this.gpsRequestListener = gpsRequestListener;
LocalBroadcastManager.getInstance(activity).registerReceiver(receiver, new IntentFilter(BROADCAST_GPS_REQ));
}
public void config(long updateInterval, long fastestInterval) {
this.updateInterval = updateInterval;
this.fastestInterval = fastestInterval;
}
public void find(LocationUpdateListener listener) {
this.locationUpdateListener = listener;
createLocationRequest();
connectGoogleApiClient();
}
private void find() {
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(locationRequest);
builder.setAlwaysShow(true);
PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
@Override
public void onResult(@NonNull LocationSettingsResult locationSettingsResult) {
Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, LocationFinder.this);
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
try {
status.startResolutionForResult(activity, GPS_REQUEST);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
Log.d(TAG, "No GPS Hardware");
break;
}
}
});
}
public void stopFinder() {
if (googleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(googleApiClient, this);
googleApiClient.disconnect();
}
try {
activity.unregisterReceiver(receiver);
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onConnected(@Nullable Bundle bundle) {
Log.d(TAG, "GoogleApiClient: Connected");
find();
}
@Override
public void onConnectionSuspended(int i) {
Log.d(TAG, "GoogleApiClient: onConnectionSuspended");
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
Log.d(TAG, "GoogleApiClient: onConnectionFailed");
}
@Override
public void onLocationChanged(Location location) {
if (finderType != FinderType.TRACK)
stopFinder();
locationUpdateListener.onLocationUpdate(new LatLng(location.getLatitude(), location.getLongitude()));
}
public void setGpsRequestListener(GpsRequestListener gpsRequestListener) {
this.gpsRequestListener = gpsRequestListener;
}
public static void onRequestResult(Activity activity, int requestCode, int resultCode) {
if (requestCode == GPS_REQUEST) {
Intent intent = new Intent(BROADCAST_GPS_REQ);
intent.putExtra(KEY_GPS_REQ, resultCode);
LocalBroadcastManager.getInstance(activity).sendBroadcast(intent);
}
}
public enum FinderType {
// It will update the current GPS location once.
GPS,
//It will update the user location continuously.
TRACK
}
public interface LocationUpdateListener {
void onLocationUpdate(LatLng latLng);
}
public interface GpsRequestListener {
void gpsTurnedOn();
void gpsNotTurnedOn();
}
}
要获取位置更新，请按以下方式初始化类：
public class MyActivity extends AppCompatActivity implements
LocationFinder.GpsRequestListener,
LocationFinder.LocationUpdateListener {
private LocationFinder locationUpdater;
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
locationUpdater = new LocationFinder(this, LocationFinder.FinderType.TRACK);
driverLocationUpdater.gpsRequestCallback(this);
driverLocationUpdater.config(5000, 5000);
driverLocationUpdater.find(this);
}
@Override
protected void onDestroy(){
super.onDestroy()
driverLocationUpdater.stopFinder();
}
@Override
public void onLocationUpdate(LatLng latLng) {
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
LocationFinder.onRequestResult(this, requestCode, resultCode);
}
}