Question

我在提交数据时遇到问题，android.os.NetworkOnMainThreadException出现问题。请帮我解决这个问题。以下来源daftar_nama_lokasi.java：

package geotracker.lokasi;

public class daftar_nama_lokasi extends Activity{
private LocationManager lm;
private LocationListener locationListener;
private EditText lat;
private EditText lon;
private EditText nama_lokasi;
private EditText alamat_lokasi;

private EditText kode;

public void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);

    setContentView(R.layout.daftar_nama_lokasi);

    lat = (EditText) findViewById(R.id.latitude);
    lon = (EditText) findViewById(R.id.longitude);
    nama_lokasi = (EditText) findViewById(R.id.nama_lokasi);
    alamat_lokasi = (EditText) findViewById(R.id.alamat_lokasi);
    kode = (EditText) findViewById(R.id.imei);
    lat.setEnabled(false);
    lon.setEnabled(false);
    kode.setEnabled(false);


     TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
        // mendapatkan nomor imei dan menyimpanya dalam variabel
        String imei = telephonyManager.getDeviceId();
        EditText IMEI = (EditText)findViewById(R.id.imei);
        // menampilkan nomor imei pada EditView yang sudah di buat
        IMEI.setText(imei);


    // ---use the LocationManager class to obtain GPS locations---
    lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    locationListener = new MyLocationListener();
    lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);

    Button btnSimpan = (Button) findViewById(R.id.btnsimpan);
    btnSimpan.setOnClickListener(
        new OnClickListener() {
            @Override
            public void onClick(View v) {
                JSONObject json = new JSONObject();
                String hasil = "";
                try {
                    json.put("lat", lat.getText());
                    json.put("lon", lon.getText());
                    json.put("location_name", nama_lokasi.getText());
                    json.put("address", alamat_lokasi.getText());
                    json.put("imei", kode.getText());
                    koneksi_internet kn = new koneksi_internet();
                    hasil = kn.postData(json,"nama_lokasi");
                    Toast.makeText(getBaseContext(), hasil, Toast.LENGTH_SHORT).show();
                } catch (JSONException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    );
}

private class MyLocationListener implements LocationListener {
    //Menampilkan Update Lokasi GPS terkini
    @Override
    public void onLocationChanged(Location loc) {
        if (loc != null) {
            lat.setText(String.valueOf(loc.getLatitude()));
            lon.setText(String.valueOf(loc.getLongitude()));
        }
    }

    @Override
    public void onProviderDisabled(String provider) {
        // TODO Auto-generated method stub
    }

    @Override
    public void onProviderEnabled(String provider) {
        // TODO Auto-generated method stub
    }

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

konfigurasi.java

package geotracker.lokasi;

 public class konfigurasi {
final static String URL ="http://localhost/andro/config/index.php?jenis=";
final static int WAKTU = 1;// 1 menit
 }

koneksi_internet.java

package geotracker.lokasi;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;


public class koneksi_internet {
public String test(){
    return konfigurasi.URL;
}

public String postData(JSONObject json, String querystring) throws JSONException{  
    // Create a new HttpClient and Post Header
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost(konfigurasi.URL+querystring);
    //JSONObject json = new JSONObject();
    String text="";
    try {
        // JSON data:
        JSONArray postjson=new JSONArray();
        postjson.put(json);

        // Post the data:
        httppost.setHeader("json",json.toString());
        httppost.getParams().setParameter("jsonpost",postjson);

        // Execute HTTP Post Request
        System.out.print(json);
        HttpResponse response = httpclient.execute(httppost);

        // for JSON:
        if(response != null)
        {
            InputStream is = response.getEntity().getContent();

            BufferedReader reader = new BufferedReader(new          InputStreamReader(is));
            StringBuilder sb = new StringBuilder();

            String line = null;
            try {
                while ((line = reader.readLine()) != null) {
                    sb.append(line + "\n");// backslash &#92;
                }
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            text = sb.toString();
        }
    }catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
    } catch (IOException e) {
        // TODO Auto-generated catch block
    }
    return text;
}

    }

Answer 1

Android需要在单独的线程中完成数据库查询或网络操作等长时间操作。为此使用AsyncTask，因为它提供了无痛的线程，因为它可以同步你的Ui和后台线程。那么在AsyncTask的doInBackground函数中进行网络操作。

private class LongOperation extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {
postData();
       return null;
    }

    @Override
    protected void onPostExecute(String result) {
        // runs in ui thread so update views here
    }

    @Override
    protected void onPreExecute() {
//runs in ui thread start progress dialog here
}

}

代码在gingerbird上成功运行但是果酱bean错误：android.os.NetworkOnMainThreadException

1 个答案: