Question

我使用 http://api.openweathermap.org/data/2.5/weather 来显示当我使用位置设置在其中发送位置时它在模拟器中工作的天气，但它不在真实设备上工作。它甚至不会在日志中显示任何错误消息可以任何人告诉我我做错了什么？

我还在Androidmanifest.xml添加了所有权限。

MainActivity.java

public class MainActivity extends AppCompatActivity implements LocationListener {

    TextView txtCity, txtLastUpdate, txtDescription, txtHumidity, txtTime, txtCelsius;
    ImageView imageView;

    LocationManager locationManager;
    String provider;
    static double lat, lng;
    OpenWeatherMap openWeatherMap = new OpenWeatherMap();

    int MY_PERMISSION = 0;

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

        //Control
        txtCity = (TextView) findViewById(R.id.txtCity);
        txtLastUpdate = (TextView) findViewById(R.id.txtLastUpdate);
        txtDescription = (TextView) findViewById(R.id.txtDescription);
        txtHumidity = (TextView) findViewById(R.id.txtHumidity);
        txtTime = (TextView) findViewById(R.id.txtTime);
        txtCelsius = (TextView) findViewById(R.id.txtCelsius);
        imageView = (ImageView) findViewById(R.id.imageView);


        //Get Coordinates
        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        provider = locationManager.getBestProvider(new Criteria(), false);

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


            ActivityCompat.requestPermissions(MainActivity.this, new String[]{
                    Manifest.permission.INTERNET,
                    Manifest.permission.ACCESS_COARSE_LOCATION,
                    Manifest.permission.ACCESS_FINE_LOCATION,
                    Manifest.permission.ACCESS_NETWORK_STATE,
                    Manifest.permission.SYSTEM_ALERT_WINDOW,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE


            }, MY_PERMISSION);
        }
        Location location = locationManager.getLastKnownLocation(provider);
        if (location == null)
            Log.e("TAG","No Location");
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{
                    Manifest.permission.INTERNET,
                    Manifest.permission.ACCESS_COARSE_LOCATION,
                    Manifest.permission.ACCESS_FINE_LOCATION,
                    Manifest.permission.ACCESS_NETWORK_STATE,
                    Manifest.permission.SYSTEM_ALERT_WINDOW,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE


            }, MY_PERMISSION);
        }
        locationManager.removeUpdates(this);
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{
                    Manifest.permission.INTERNET,
                    Manifest.permission.ACCESS_COARSE_LOCATION,
                    Manifest.permission.ACCESS_FINE_LOCATION,
                    Manifest.permission.ACCESS_NETWORK_STATE,
                    Manifest.permission.SYSTEM_ALERT_WINDOW,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE


            }, MY_PERMISSION);
        }
        locationManager.requestLocationUpdates(provider, 400, 1, this);
    }

    @Override
    public void onLocationChanged(Location location) {
        lat = location.getLatitude();
        lng = location.getLongitude();

        new GetWeather().execute(Common.apiRequest(String.valueOf(lat),String.valueOf(lng)));
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override
    public void onProviderEnabled(String provider) {

    }

    @Override
    public void onProviderDisabled(String provider) {

    }

    private class GetWeather extends AsyncTask<String,Void,String>{
        ProgressDialog pd = new ProgressDialog(MainActivity.this);


        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pd.setTitle("Please wait...");
            pd.show();

        }


        @Override
        protected String doInBackground(String... params) {
            String stream = null;
            String urlString = params[0];

            Helper http = new Helper();
            stream = http.getHTTPData(urlString);
            return stream;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            if(s.contains("Error: Not found city")){
                pd.dismiss();
                return;
            }
            Gson gson = new Gson();
            Type mType = new TypeToken<OpenWeatherMap>(){}.getType();
            openWeatherMap = gson.fromJson(s,mType);
            pd.dismiss();

            txtCity.setText(String.format("%s,%s",openWeatherMap.getName(),openWeatherMap.getSys().getCountry()));
            txtLastUpdate.setText(String.format("Last Updated: %s", Common.getDateNow()));
            txtDescription.setText(String.format("%s",openWeatherMap.getWeather().get(0).getDescription()));
            txtHumidity.setText(String.format("%d%%",openWeatherMap.getMain().getHumidity()));
            txtTime.setText(String.format("%s/%s",Common.unixTimeStampToDateTime(openWeatherMap.getSys().getSunrise()),Common.unixTimeStampToDateTime(openWeatherMap.getSys().getSunset())));
            txtCelsius.setText(String.format("%.2f °C",openWeatherMap.getMain().getTemp()));
            Picasso.with(MainActivity.this)
                    .load(Common.getImage(openWeatherMap.getWeather().get(0).getIcon()))
                    .into(imageView);

        }

    }
}

Common.java

public class Common {
public static String API_KEY = "mykey";
public static String API_LINK = "http://api.openweathermap.org/data/2.5/weather";

@NonNull
public static String apiRequest(String lat, String lng){
    StringBuilder sb = new StringBuilder(API_LINK);
    sb.append(String.format("?lat=%s&lon=%s&APPID=%s&units=metric",lat,lng,API_KEY));
    return sb.toString();
}

public static String unixTimeStampToDateTime(double unixTimeStamp){
    DateFormat dateFormat = new SimpleDateFormat("HH:mm");
    Date date = new Date();
    date.setTime((long)unixTimeStamp*1000);
    return dateFormat.format(date);
}

public static String getImage(String icon){
    return String.format("http://openweathermap.org/img/w/%s.png",icon);
}

public static String getDateNow(){
    DateFormat dateFormat = new SimpleDateFormat("dd MMMM yyyy HH:mm");
    Date date = new Date();
    return dateFormat.format(date);
}

}

Answer 1

方法getLastKnownLocation在上次获取位置信息时，它可能为空。

您可以参考关键字的其他问题：getLastKnownLocation return null

这些问题对你有帮助，可能是。

getlastknownlocation always return null after I re-install the apk file via eclipse

getLastKnownLocation returns null

在真实设备上运行时未显示天气

1 个答案: