手机重启后，Android获取位置为空 [英] Android get location is null after phone reboot

问题描述

在我的应用程序中，我通过此功能获取手机的位置，但是当我重新启动手机并启动应用程序时，此方法得到的结果为null.有什么我想念或做错的事吗?我该怎么做才能解决此问题?

In my app im getting the phone's location via this function, but when I restart the phone and start the app I get null from this method. Is there something that im missing or doing wrong? What should I do to fix this issue?

这是我正在使用的函数:

Here is the function im using:

public void getAddress() {
        Log.v("--", "get address 1");
        boolean isGPSProviderEnabled = locationManager
                .isProviderEnabled(LocationManager.GPS_PROVIDER);
        boolean network_enabled = locationManager
                .isProviderEnabled(LocationManager.NETWORK_PROVIDER);
        Log.v("--", "get address 31 " + isGPSProviderEnabled + " gps  -  "
                + isConnectedToNetwork());

        if (isGPSProviderEnabled || network_enabled) {
            Log.v("--", "get address 2");
            Criteria c = new Criteria();
            Log.v("--", "provider " + locationManager.getBestProvider(c, true));
            locationManager.requestSingleUpdate(
                    locationManager.getBestProvider(c, true),
                    mLocationListener, Looper.myLooper());
            location = locationManager.getLastKnownLocation(locationManager
                    .getBestProvider(c, true));
            if (location == null) {
                Log.v("--", "get address 6");
                // TODO check if this is working
                locationManager.requestSingleUpdate(
                        locationManager.getBestProvider(c, true),
                        mLocationListener, Looper.myLooper());
                locationManager.requestLocationUpdates(
                        locationManager.getBestProvider(c, true), 0, 0,
                        mLocationListener);
                Location oldLocation = new Location("");
                oldLocation.setLatitude(new Double(prefs.getString(
                        Constants.LATITUDE, "48.51")));
                oldLocation.setLongitude(new Double(prefs.getString(
                        Constants.LONGITUDE, "2.20")));
                populateList(oldLocation);
                // locationManager.requestLocationUpdates(
                // locationManager.getBestProvider(c, true), 1000, 100,
                // mLocationListener);
            } else {
                Log.v("--", "get address 3");
                if (isConnectedToNetwork()) {
                    new AsyncTask<Void, Void, Void>() {
                        protected Void doInBackground(Void... params) {
                            try {
                                com.quanticapps.athan.utils.Geocoder geocoder = new com.quanticapps.athan.utils.Geocoder(
                                        Main.this);
                                GeocoderModel geocoderModel = geocoder
                                        .getFromLocation(
                                                location.getLatitude(),
                                                location.getLongitude(), 5);
                                city = geocoderModel.getCity();
                                country = geocoderModel.getCountry();
                                prefs.edit().putString(Constants.CITY, city)
                                        .apply();
                                Log.v("--", "get address 4");
                            } catch (IOException e) {
                                Log.v("--", "get address 11");
                                e.printStackTrace();
                            } catch (LimitExceededException e) {
                                Log.v("--", "get address 12");
                                e.printStackTrace();
                            }
                            return null;
                        };

                        protected void onPostExecute(Void result) {
                            prefs.edit().putString(Constants.COUNTRY, country)
                                    .apply();
                            prefs.edit().putString(Constants.CITY, city)
                                    .apply();
                            populateList(location);
                        };
                    }.execute();
                } else {
                    city = null;
                    Log.v("--", "get address 33 " + location.getLatitude());
                    populateList(location);
                }
            }
        } else {
            Log.v("--", "get address 5");
            startGpsEnableDialog();
        }

    }

和我的位置监听器:

private final LocationListener mLocationListener = new LocationListener() {
        @Override
        public void onLocationChanged(final Location location) {
            // TODO
            Log.v("--", "get address 121");
            if (location != null) {
                Main.this.location = location;
                getAddress();
            }
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onProviderEnabled(String provider) {
            // TODO Auto-generated method stub
            Log.v("--", "provider enabled");
        }

        @Override
        public void onProviderDisabled(String provider) {
            // TODO Auto-generated method stub
            Log.v("--", "provider disabled");
        }
    };

推荐答案

重新启动手机后，缓存的最后一个位置将丢失，因此，如果您未打开使用GPS的应用程序(例如google maps或Google Maps)，则将没有最后的位置位置.

When the phone is rebooted the cached last location is lost so if you didnt open up an app that uses GPS like google maps or something then there will be no last location.

您不必再返回任何位置，您应该始终假定它可以为空

There never has to be a location returned to you, you should always assume it could be null

这篇关于手机重启后，Android获取位置为空的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！