在Android上使用Google Places API获取附近地点的列表

Question

I'm using this What is the simplest and most robust way to get the user's current location on Android? to get my current location and list nearby restaurants when i click on swith button.It works before i remove the app and install it again. this is my implementation of gotLocation method

switchCompat.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                if (isChecked){
                    MyLocationManager.LocationResult locationResult= new MyLocationManager.LocationResult() {
                        @Override
                        public void gotLocation(final Location location) {
                            //Got the location!


                                    currentLocation = location;
                                    browseNearbyBusinessesList(currentLocation);

                        }
                        };
                    MyLocationManager myLocationManager = new MyLocationManager();
                    myLocationManager.getLocation(getBaseContext(), locationResult);
                }else {
                    searchDefaultList();
                }
            }
        });

I got not null LocationResult Object but the gotLocation method was not executed . Can any one tell me where is exactly the problem please?

this is the code of MyLocationManager Class

public class MyLocationManager {
    public LocationResult locationResult;
    public Context context;
    Timer timer1;
    LocationManager lm;
    boolean gps_enabled = false;
    boolean network_enabled = false;
    LocationListener locationListenerGps = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerNetwork);
        }

        public void onProviderDisabled(String provider) {
        }

        public void onProviderEnabled(String provider) {
        }

        public void onStatusChanged(String provider, int status, Bundle extras) {
        }
    };
    LocationListener locationListenerNetwork = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerGps);
        }

        public void onProviderDisabled(String provider) {
        }

        public void onProviderEnabled(String provider) {
        }

        public void onStatusChanged(String provider, int status, Bundle extras) {
        }
    };
    private boolean isPermessed = false;

    public MyLocationManager() {

    }

    public MyLocationManager(boolean isPermessed) {
        this.isPermessed = isPermessed;
    }

    public boolean getLocation(Context context, LocationResult result) {
        //I use LocationResult callback class to pass location value from MyLocation to user code.
        this.context = context;
        locationResult = result;
        if (lm == null)
            lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);

        //exceptions will be thrown if provider is not permitted.
        try {
            gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
        } catch (Exception ex) {
        }
        try {
            network_enabled = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
        } catch (Exception ex) {
        }

        //don't start listeners if no provider is enabled
        if (!gps_enabled && !network_enabled)
            return false;

        if (gps_enabled) {
            if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

                isPermessed = false;
                return false;

            } else {
                isPermessed = true;
            }
            if (isPermessed)
                lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
        }
        if (network_enabled) {
            if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

                isPermessed = false;
                return false;
            } else {
                isPermessed = true;
            }
            if (isPermessed)
                lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
        }

        timer1 = new Timer();
        timer1.schedule(new GetLastLocation(), 4000);
        return true;
    }

    public static abstract class LocationResult {
        public abstract void gotLocation(final Location location);
    }

    class GetLastLocation extends TimerTask {
        @Override
        public void run() {
            lm.removeUpdates(locationListenerGps);
            lm.removeUpdates(locationListenerNetwork);

            Location net_loc = null, gps_loc = null;
            if (gps_enabled) {

                if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    isPermessed = false;
                    return;
                } else {
                    isPermessed = true;
                }
                if (isPermessed)
                    gps_loc = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            }
            if (network_enabled) {
                if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    isPermessed = false;
                    return;
                } else {
                    isPermessed = true;
                }
                if (isPermessed)
                    net_loc = lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            }
            System.out.println(isPermessed);
            //if there are both values use the latest one
            if (gps_loc != null && net_loc != null) {
                if (gps_loc.getTime() > net_loc.getTime())
                    locationResult.gotLocation(gps_loc);
                else
                    locationResult.gotLocation(net_loc);
                return;
            }

            if (gps_loc != null) {
                locationResult.gotLocation(gps_loc);
                return;
            }
            if (net_loc != null) {
                locationResult.gotLocation(net_loc);
                return;
            }
            locationResult.gotLocation(null);
        }
    }

}

Answer 1

The problem was isPermissed returns always false. I created a method getLocationPermissions() to grant permissions.

        private final static String FINE_LOCATION= Manifest.permission.ACCESS_FINE_LOCATION;
        private final static String COARSE_LOCATION= Manifest.permission.ACCESS_COARSE_LOCATION;
        private final static int LOCATION_PERMISSION_REQUEST_CODE=1234;
                   --------------------------------------

        if (gps_enabled) {
                    getLocationPermission();
                    if (((ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) && (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED))) {

                        isPermessed = true;
                        Log.i("isPermessed = ", isPermessed+"");

                    } else {
                        isPermessed = false;
                        Log.i("isPermessed = ", isPermessed+"");
                        return false;


                    }

                     --------------------------------------
 private void getLocationPermission() {
        String[] permissions = {android.Manifest.permission.ACCESS_FINE_LOCATION,
                android.Manifest.permission.ACCESS_COARSE_LOCATION};

        if (ContextCompat.checkSelfPermission(context,
                FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
            if (ContextCompat.checkSelfPermission(context,
                    COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
            } else {
                ActivityCompat.requestPermissions((Activity) context,
                        permissions,
                        LOCATION_PERMISSION_REQUEST_CODE);
            }
        } else {
            ActivityCompat.requestPermissions((Activity) context,
                    permissions,
                    LOCATION_PERMISSION_REQUEST_CODE);
        }
    }