java - Android 获取用户位置一次

Question

我知道这方面有很多问题，但即使我(几乎)读完了所有内容，我仍然无法弄清楚问题所在。

基本上，当我打开应用程序或按下按钮并保存在共享首选项时，我希望让用户获得“精细位置”。 我的旧代码可以工作，但由于获取坐标的速度很慢，因此无法保存共享首选项(GPS 图标不显示在栏上)。

旧:

 public void askLocation() {
    if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
        LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
        Criteria criteria = new Criteria();
        String provider = locationManager.getBestProvider(criteria, true);
        try {
            mLocation = locationManager.getLastKnownLocation(provider);
        } catch (SecurityException e) {
            //
        }

        String currentCoordinates = somename.getString("LastLocation", "0,0");

        if (mLocation != null) {
            double currentLatitude = mLocation.getLatitude();
            double currentLongitude = mLocation.getLongitude();

            currentCoordinates = currentLatitude + "," + currentLongitude;
        }

        SharedPreferences.Editor editor = somename.edit();
        editor.putString("LastLocation", currentCoordinates).commit();

        Log.d("SomeName", "lastLocation start: " + currentCoordinates);
    }
}

我的新代码(从 Stackoverflow 上的帖子中使用)未正确获取(GPS 图标显示在栏上):

public void askLocation() {
    if (ContextCompat.checkSelfPermission(MainActivity.this,                                                 Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)         {
        Criteria criteria = new Criteria();
        criteria.setAccuracy(Criteria.ACCURACY_COARSE);
        criteria.setPowerRequirement(Criteria.POWER_LOW);
        criteria.setAltitudeRequired(false);
        criteria.setBearingRequired(false);
        criteria.setSpeedRequired(false);
        criteria.setCostAllowed(true);
        criteria.setHorizontalAccuracy(Criteria.ACCURACY_HIGH);
        criteria.setVerticalAccuracy(Criteria.ACCURACY_HIGH);

        // Now create a location manager
        LocationManager locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
        Looper looper = null;
        locationManager.requestSingleUpdate(criteria, locationListener, looper);

        String currentCoordinates = somename.getString("LastLocation", "0,0");
        Log.d("SomeName", "lastLocation askLocation: " + currentCoordinates);
    }
}

final LocationListener locationListener = new LocationListener() {
    @Override
    public void onLocationChanged(Location location) {
        mLocation = location;
        String currentCoordinates = somename.getString("LastLocation", "0,0");

        if (location != null) {
            double currentLatitude = location.getLatitude();
            double currentLongitude = location.getLongitude();

            currentCoordinates = currentLatitude + "," + currentLongitude;
        }

        SharedPreferences.Editor editor = somename.edit();
        editor.putString("LastLocation", currentCoordinates).commit();
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
        Log.d("Status Changed", String.valueOf(status));
    }

    @Override
    public void onProviderEnabled(String provider) {
        Log.d("Provider Enabled", provider);
    }

    @Override
    public void onProviderDisabled(String provider) {
        Log.d("Provider Disabled", provider);
    }
};

谢谢。

Answer 1

您可以尝试此方法在打开应用程序或按按钮并保存在共享首选项时获取位置。

               if (Constants.isOnline(getApplicationContext())) {
                        gps = new GPSTracker(v.getContext(),this);
                        if (gps.canGetLocation()) {

                            latitude = gps.getLatitude();
                            longitude = gps.getLongitude();
                            Log.e("Location ", "latitude : " + latitude + "longitude :" + longitude);

                        } else {
                            gps.showSettingsAlert();
                        }
                }

isOnline() 用于检查用户是否有互联网连接。

 public static boolean isOnline(Context c) {
    ConnectivityManager cm = (ConnectivityManager) c.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo netInfo = cm.getActiveNetworkInfo();
    if (netInfo != null && netInfo.isConnectedOrConnecting()) {
        return true;
    } else {
        Toast.makeText(c, "No Internet Connection.", Toast.LENGTH_SHORT).show();
    }
return false;

}