Question

有谁知道为什么凌空重复它的反应？香港专业教育学院已花了2个小时搞清楚为什么会这样。我发送重复的请求？或者在1个请求中向我发送重复数据？

 SwipeRefreshLayout swipe;
ListView list;
CustomListAdapter adapter;
List <Distance> itemList = new ArrayList <>();
Double latitude, longitude;
Criteria criteria;
Location location;
LocationManager locationManager;
String provider;


private static final String url = "https://phagedenic-roots.000webhostapp.com/thesis/haversine.php?latt=";

public ListViewFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_list_view, container, false);
    list = (ListView) view.findViewById(R.id.list);
    swipe = (SwipeRefreshLayout) view.findViewById(R.id.swipe);

    // mengisi data dari adapter ke listview
    adapter = new CustomListAdapter(getActivity(), itemList);
    list.setAdapter(adapter);

    locationManager = (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE);
    criteria = new Criteria();

    provider = locationManager.getBestProvider(criteria, false);


    swipe.setOnRefreshListener(this);

    swipe.post(new Runnable() {
        @Override
        public void run() {
            location();
        }

    });

    return view;
}

@Override
public void onRefresh() {
    location();
}

private void location() {
    if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        // TODO: Consider calling
        //    ActivityCompat#requestPermissions
        // here to request the missing permissions, and then overriding
        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
        //                                          int[] grantResults)
        // to handle the case where the user grants the permission. See the documentation
        // for ActivityCompat#requestPermissions for more details.
        return;
    }
    location = locationManager.getLastKnownLocation(provider);
    if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) !=
            PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(),
            Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        // TODO: Consider calling
        //    ActivityCompat#requestPermissions
        // here to request the missing permissions, and then overriding
        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
        //                                          int[] grantResults)
        // to handle the case where the user grants the permission. See the documentation
        // for ActivityCompat#requestPermissions for more details.
        return;
    }

    // request location update of device within per second
    locationManager.requestLocationUpdates(provider, 1000, 1, (LocationListener) this);

    if (location != null) {
       onLocationChanged(location);
    } else {
       /* latitude longitude Alun-alun Demak sebagai default jika tidak ditemukan lokasi dari device pengguna */
        callListVolley(13.138075, 123.735694);
    }
}

private void callListVolley(double lat, double lng) {
    itemList.clear();
    adapter.notifyDataSetChanged();

    swipe.setRefreshing(true);

    JsonArrayRequest jArr = new JsonArrayRequest(url + lat + "&longt=" + lng,
            new Response.Listener<JSONArray>() {
                @Override
                public void onResponse(JSONArray response) {
                    Log.e(TAG, response.toString());

                    // Parsing json
                    for (int i = 0; i < response.length(); i++) {
                        try {

                            JSONObject obj = response.getJSONObject(i);
                            Distance j = new Distance();
                            j.setApartmentname(obj.getString("apartmentName"));
                            j.setPrice(obj.getString("price_month"));
                            j.setCategory(obj.getString("Category"));

                            double distance = Double.parseDouble(obj.getString("distance"));

                            j.setDistance("" + round(distance, 2));

                            itemList.add(j);

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }

                    // memberitahu adapter jika ada perubahan data
                    adapter.notifyDataSetChanged();

                    swipe.setRefreshing(false);
                }
            }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            VolleyLog.e(TAG, "Error: " + error.getMessage());
            Toast.makeText(getContext(), error.getMessage(), Toast.LENGTH_LONG).show();
            swipe.setRefreshing(false);
        }
    });

    // menambah permintaan ke queue
    AppController.getInstance().addToRequestQueue(jArr);
}

public void onBackPressed() {
    getActivity().finish();
    System.exit(0);
}
// to get the shortest distance
public static double round(double value, int places) {
    if (places < 0) throw new IllegalArgumentException();

    long factor = (long) Math.pow(10, places);
    value = value * factor;
    long tmp = Math.round(value);
    return (double) tmp / factor;
}

// location of the current user
@Override
public void onLocationChanged(Location location) {
    latitude = location.getLatitude();
    longitude = location.getLongitude();


    Log.e(TAG, "User location latitude:" + latitude + ", longitude:" + longitude);

    callListVolley(latitude, longitude);
}

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

}

@Override
public void onProviderEnabled(String provider) {

}

@Override
public void onProviderDisabled(String provider) {

}

}

这是logcat的响应。我花了2个小时才弄明白它的错误是什么:(请帮忙。

Answer 1

你的排球请求工作正常。您只需输入两次onLocationChanged(Location location)，这意味着您的位置提供商会向您发送最后一个已知位置，并且可能会立即发送更新。我怀疑您的问题来自location()中的onResume()。您应该设置LocationManager并在requestLocationUpdates中请求onCreate()，并仅在onResume()中保留权限管理部分。这只是我的猜测，我没有尝试修改你的代码，因为我现在没有足够的时间.`

为什么我会得到重复的截击响应？

1 个答案: