private LocationManager locationManager;
private LocationListener listener;

static float lat;
static float lon;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction().add(R.id.container, new WeatherFragment()).commit();
    }


    locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);


    listener = new LocationListener() {
        @Override
        public void onLocationChanged(Location location) {
            lat = (float)location.getLatitude();
            lon = (float)location.getLongitude();

            //t.setText("n " + lat + "n" + lon);
        }

        @Override
        public void onStatusChanged(String s, int i, Bundle bundle) {

        }

        @Override
        public void onProviderEnabled(String s) {

        }

        @Override
        public void onProviderDisabled(String s) {

            Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
            startActivity(i);
        }
    };

    configure_button();


}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.weather, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if(item.getItemId() == R.id.change_city){
        showInputDialog();
    }
    return false;
}

private void showInputDialog(){
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Escolher a Cidade:");
    final EditText input = new EditText(this);
    input.setInputType(InputType.TYPE_CLASS_TEXT);
    builder.setView(input);
    builder.setPositiveButton("Go", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            changeCity(input.getText().toString());
        }
    });
    builder.show();
}

public void changeCity(String city){
    WeatherFragment wf = (WeatherFragment)getSupportFragmentManager()
            .findFragmentById(R.id.container);
    wf.changeCity(city);
    new CityPreference(this).setCity(city);
}


@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    switch (requestCode){
        case 10:
            configure_button();
            break;
        default:
            break;
    }
}

void configure_button(){
    // first check for permissions
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION,Manifest.permission.ACCESS_FINE_LOCATION,Manifest.permission.INTERNET}
                    ,10);
        }
        return;
    }
    // this code won't execute IF permissions are not allowed, because in the line above there is return statement.

    //noinspection MissingPermission
    locationManager.requestLocationUpdates("gps", 5000, 0, listener);
}

//private static final String OPEN_WEATHER_MAP_API = "http://api.openweathermap.org/data/2.5/weather?q=%s&units=metric";


//private static final String OPEN_WEATHER_MAP_API = "http://api.openweathermap.org/data/2.5/weather?lat=35&lon=139&units=metric";

private static final String OPEN_WEATHER_MAP_API = "http://api.openweathermap.org/data/2.5/weather?lat=" + lat + "&lon=" + lon + "&units=metric";



public static JSONObject getJSON(Context context, String city){
    try {
        URL url = new URL(String.format(OPEN_WEATHER_MAP_API, city));
        HttpURLConnection connection =
                (HttpURLConnection)url.openConnection();

        connection.addRequestProperty("x-api-key", context.getString(R.string.open_weather_maps_app_id));

        BufferedReader reader = new BufferedReader(
                new InputStreamReader(connection.getInputStream()));

        StringBuffer json = new StringBuffer(1024);
        String tmp="";
        while((tmp=reader.readLine())!=null)
            json.append(tmp).append("n");
        reader.close();

        JSONObject data = new JSONObject(json.toString());

        if(data.getInt("cod") != 200){
            return null;
        }

        return data;
    }catch(Exception e){
        return null;
    }
}

Typeface weatherFont;

TextView cityField;
TextView updatedField;
TextView detailsField;
TextView currentTemperatureField;
TextView weatherIcon;

TextView windField;

Handler handler;

public WeatherFragment(){
    handler = new Handler();
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_weather, container, false);
    cityField = (TextView)rootView.findViewById(R.id.city_field);
    updatedField = (TextView)rootView.findViewById(R.id.updated_field);
    detailsField = (TextView)rootView.findViewById(R.id.details_field);
    currentTemperatureField = (TextView)rootView.findViewById(R.id.current_temperature_field);
    weatherIcon = (TextView)rootView.findViewById(R.id.weather_icon);

    windField = (TextView)rootView.findViewById(R.id.wind_detail);

    weatherIcon.setTypeface(weatherFont);
    return rootView;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    weatherFont = Typeface.createFromAsset(getActivity().getAssets(), "weather.ttf");
    updateWeatherData(new CityPreference(getActivity()).getCity());
}

private void updateWeatherData(final String city){
    new Thread(){
        public void run(){
            final JSONObject json = RemoteFetch.getJSON(getActivity(), city);
            if(json == null){
                handler.post(new Runnable(){
                    public void run(){
                        Toast.makeText(getActivity(),
                                getActivity().getString(R.string.place_not_found),
                                Toast.LENGTH_LONG).show();
                    }
                });
            } else {
                handler.post(new Runnable(){
                    public void run(){
                        renderWeather(json);
                    }
                });
            }
        }
    }.start();
}

private void renderWeather(JSONObject json){
    try {
        cityField.setText(json.getString("name").toUpperCase(Locale.US) +
                ", " +
                json.getJSONObject("sys").getString("country"));

        JSONObject details = json.getJSONArray("weather").getJSONObject(0);
        JSONObject main = json.getJSONObject("main");
        detailsField.setText(
                details.getString("description").toUpperCase(Locale.US) +
                "n" + "Humidity: " + main.getString("humidity") + "%" +
                "n" + "Pressure: " + main.getString("pressure") + " hPa");

        JSONObject wind = json.getJSONObject("wind");

        //converter para km/h
        double wind_ms = Double.parseDouble(wind.getString("speed").toUpperCase(Locale.getDefault()));
        double wind_km = wind_ms * 3.6;
        //DecimalFormat decimal = new DecimalFormat("#.##");
        //wind_km = Double.valueOf(decimal.format(wind_km));
        windField.setText("Wind: " + wind_km + " Km/h   ");


        currentTemperatureField.setText(
                    String.format("%.2f", main.getDouble("temp"))+ " ℃");

        DateFormat df = DateFormat.getDateTimeInstance();
        String updatedOn = df.format(new Date(json.getLong("dt")*1000));
        updatedField.setText("Last update: " + updatedOn);

        setWeatherIcon(details.getInt("id"),
                json.getJSONObject("sys").getLong("sunrise") * 1000,
                json.getJSONObject("sys").getLong("sunset") * 1000);

    }catch(Exception e){
        Log.e("SimpleWeather", "One or more fields not found in the JSON data");
    }
}

private void setWeatherIcon(int actualId, long sunrise, long sunset){
    int id = actualId / 100;
    String icon = "";
    if(actualId == 800){
        long currentTime = new Date().getTime();
        if(currentTime>=sunrise && currentTime<sunset) {
            icon = getActivity().getString(R.string.weather_sunny);
        } else {
            icon = getActivity().getString(R.string.weather_clear_night);
        }
    } else {
        switch(id) {
        case 2 : icon = getActivity().getString(R.string.weather_thunder);
                 break;
        case 3 : icon = getActivity().getString(R.string.weather_drizzle);
                 break;
        case 7 : icon = getActivity().getString(R.string.weather_foggy);
                 break;
        case 8 : icon = getActivity().getString(R.string.weather_cloudy);
                 break;
        case 6 : icon = getActivity().getString(R.string.weather_snowy);
                 break;
        case 5 : icon = getActivity().getString(R.string.weather_rainy);
                 break;
        }
    }
    weatherIcon.setText(icon);
}

public void changeCity(String city){
    updateWeatherData(city);
}