致命异常:AsyncTask#1,java.lang.RuntimeException:执行doInBackground()时发生错误
我在android设备上构建我的代码时出错。 其错误报告致命异常:AsyncTask#1,java.lang.RuntimeException:执行doInBackground()时发生错误
9月5日至17日:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:致命异常:#的AsyncTask 1 9月5日至17日:47:16.035 17982 -18134/com.example.ckw.mapku E/AndroidRuntime:进程:com.example.ckw.mapku,PID:17982 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime :java.lang.RuntimeException:执行doInBackground()时发生错误 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at android.os.AsyncTask $ 3.done(AsyncTask .java:300) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util.concurrent.FutureTask.run(FutureTask.java:242) 05-17 09:47:16.035 17982-18134/com.example.ckw .mapku E/AndroidRuntime:at android.os.AsyncTask $ SerialExecutor $ 1.run(AsyncTask.java:231) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at java .util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util.concurrent.ThreadPoolExecutor $ Worker。运行(ThreadPoolExecutor.java:587) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at java.lang.Thread.run( Thread.java:841) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:导致:java.lang.NullPointerException 05-17 09:47:16.035 17982-18134 /com.example.ckw.mapku E/AndroidRuntime:at com.example.ckw.mapku.ServiceHandler.makeHttpRequest(ServiceHandler.java:71) 05-17 09:47:16.035 17982-18134/com.example.ckw。 mapku E/AndroidRuntime:at com.example.ckw.mapku.ServiceHandler.makeHttpRequest(ServiceHandler.java:33) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at com .example.ckw.mapku.Hasil_pencarian $ GetMedik.doInBackground(Hasil_pencarian.java:77) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:at com.example.ckw。 mapku.Hasil_pencarian $ GetMedik.doInBackground(Hasil_pencarian.java:60) 05-17 09:47:16.035 17982-18134/com.example.ckw.map ku E/AndroidRuntime:at android.os.AsyncTask $ 2.call(AsyncTask.java:288) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util。并发.FutureTask.run(FutureTask.java:237) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在android.os.AsyncTask $ SerialExecutor $ 1.run(AsyncTask。 java:231) 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 05-17 09 :47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在java.util.concurrent.ThreadPoolExecutor $ Worker.run(ThreadPoolExecutor.java:587) 05-17 09:47:16.035 17982-18134 /com.example.ckw.mapku E/AndroidRuntime:在java.lang.Thread.run(Thread。Java的:841)
,这是我的代码
package com.example.ckw.mapku;
import android.app.ProgressDialog;
import android.app.Service;
import android.os.AsyncTask;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import org.apache.http.HttpEntity;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONStringer;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
public class Hasil_pencarian extends AppCompatActivity {
String myJSON;
private static final String TAG_RESULT = "result";
private static final String TAG_ID = "id_lay";
private static final String TAG_NAME = "Nama";
private static final String TAG_LONG = "Longitude";
private static final String TAG_LAT = "Latitude";
JSONArray layanan = null;
ArrayList<HashMap<String, String>> layananList;
ListView list;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_hasil_pencarian);
list = (ListView) findViewById(R.id.listView);
layananList = new ArrayList<HashMap<String, String>>();
new GetMedik().execute();
}
private class GetMedik extends AsyncTask<String, Void, JSONObject>{
private ProgressDialog progressDialog;
private static final String ALAMAT = "http://rugimuleh.com/medikmap/medik.php";
@Override
protected void onPreExecute(){
progressDialog = new ProgressDialog(Hasil_pencarian.this);
progressDialog.setMessage("Tunggu sebentar...");
progressDialog.setCancelable(false);
progressDialog.show();
}
@Override
protected JSONObject doInBackground(String... arg0) {
ServiceHandler sh = new ServiceHandler();
JSONObject jsonStr = sh.makeHttpRequest(ALAMAT, "GET");
Log.d("JSON result ", jsonStr.toString());
myJSON = jsonStr.toString();
if (jsonStr != null) {
try {
JSONObject jsonObject = new JSONObject(myJSON);
layanan = jsonObject.getJSONArray(TAG_RESULT);
for (int i=0;i<layanan.length();i++){
JSONObject c = layanan.getJSONObject(i);
String id_lay = c.getString(TAG_ID);
String Nama = c.getString(TAG_NAME);
String Longitude = c.getString(TAG_LONG);
String Latitude = c.getString(TAG_LAT);
HashMap<String, String> medik = new HashMap<String, String>();
medik.put(TAG_ID, id_lay);
medik.put(TAG_NAME, Nama);
medik.put(TAG_LONG, Longitude);
medik.put(TAG_LAT, Latitude);
layananList.add(medik);
}
}catch (Exception e) {
e.printStackTrace();
}
}else {
Log.e("ServiceHandler", "Couldn't get any data from the url");}
return null;
}
protected void onPostExecute(JSONObject result){
super.onPostExecute(result);
if(progressDialog.isShowing())
progressDialog.dismiss();
ListAdapter adapter = new SimpleAdapter(
Hasil_pencarian.this, layananList, R.layout.list_item,
new String[]{TAG_ID, TAG_NAME, TAG_LONG, TAG_LAT},
new int[]{R.id.id_lay, R.id.Nama, R.id.Longitude, R.id.Latitude}
);
list.setAdapter(adapter);
}
}
}
检查一个NullPointerException异常这里:
JSONObject jsonStr = sh.makeHttpRequest(ALAMAT, "GET");
引起:java.lang中.NullPointerException 05-17 09:47:16.035 17982-18134/com.example.ckw.mapku E/AndroidRuntime:在 com.example.ckw.mapku.ServiceHandler.makeHttpRequest(ServiceHandler.java:71)
好吧,我明白了。问题出在我的声明中。谢谢。但我又有一个问题。当我的应用程序运行时没有错误,但我的php不能显示在我的应用程序中的数据。如何回合 –
@StepHanusCkw,可以继续作为另一个问题,这应该是足够的本身:) – nullpointer
好ty为您的帮助@nullpointer –
有来自抛出显示java.lang.NullPointerException ServiceHandler.java的第71行。您应该检查该文件。 –
好吧,我明白了。这非常有帮助谢谢 –