Android doInBackground Fatal expection Asynctask #1

Question

My app crashes after I try to work in the background with json. I don't know why it doesn't work.

Class:

  package com.example.olda.hledac;
  import android.app.ProgressDialog;
  import android.content.Intent;
  import android.os.AsyncTask;
  import android.os.Bundle;
  import android.util.Log;
  import android.view.View;
  import android.widget.AdapterView;
  import android.widget.AdapterView.OnItemClickListener;
  import android.widget.ListAdapter;
  import android.widget.ListView;
  import android.widget.SimpleAdapter;
  import android.widget.TextView;
  import android.app.ListActivity;

  import org.apache.http.NameValuePair;
  import org.json.JSONArray;
  import org.json.JSONException;
  import org.json.JSONObject;

  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;


  public class vypis extends ListActivity {

private ProgressDialog pDialog;

JSONParser jParser = new JSONParser();

ArrayList<HashMap<String, String>> uzivatele;


private static String url = "http://lokace.4fan.cz/vypis_uzivatelu.php";

private static final String TAG_SUCCESS = "success";
private static final String TAG_WP_USERS = "wp_users";
private static final String TAG_ID = "ID";
private static final String TAG_USER_login = "user_login";

JSONArray uziv = null;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_vypis);
    ListView lv = getListView();
    uzivatele = new ArrayList<HashMap<String, String>>();
        new VypisUzivatele().execute();


        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
                String ID = ((TextView) view.findViewById(R.id.ID)).getText()
                        .toString();

                Intent in = new Intent(getApplicationContext(),
                        MenuActivity.class);
                in.putExtra(TAG_ID, ID);
                startActivityForResult(in, 100);
            }
        });

    }

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == 100) {
        Intent intent = getIntent();
        finish();
        startActivity(intent);
    }

}

 class VypisUzivatele extends AsyncTask<String, String, String> {

   @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(vypis.this);
        pDialog.setMessage("vypisování uživatelů");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }


     protected String doInBackground(String... args) {
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        JSONObject json = jParser.makeHttpRequest(url, "GET", params);
         Log.d("All Products: ", json.toString());

         try {
            int success = json.getInt(TAG_SUCCESS);

            if (success == 1) {
                uziv = json.getJSONArray(TAG_WP_USERS);

                for (int i = 0; i < uziv.length(); i++) {
                    JSONObject c = uziv.getJSONObject(i);

                    String id = c.getString(TAG_ID);
                    String name = c.getString(TAG_USER_login);


                    HashMap<String, String> map = new HashMap<String, String>();


                    map.put(TAG_ID, id);
                    map.put(TAG_USER_login, name);


                    uzivatele.add(map);
                }
            } else {

                Intent i = new Intent(getApplicationContext(),
                        MenuActivity.class);

                i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(i);
            }
        } catch (JSONException e) {
            e.printStackTrace();

        }

        return null;
    }


    protected void onPostExecute(String file_url) {
        pDialog.dismiss();

        runOnUiThread(new Runnable() {
            public void run() {

                ListAdapter adapter = new SimpleAdapter(
                        vypis.this, uzivatele,
                        R.layout.activity_uzivatele, new String[] { TAG_ID,
                        TAG_USER_login},
                        new int[] { R.id.ID, R.id.name });
                setListAdapter(adapter);
            }
        });

    }

}

Log:

    03-30 15:56:42.056    3999-4353/com.example.olda.hledac E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
    Process: com.example.olda.hledac, PID: 3999
    java.lang.RuntimeException: An error occured while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:300)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
     Caused by: java.lang.NullPointerException
            at com.example.olda.hledac.vypis$VypisUzivatele.doInBackground(vypis.java:98)
            at com.example.olda.hledac.vypis$VypisUzivatele.doInBackground(vypis.java:82)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
03-30 15:56:42.696    3999-3999/com.example.olda.hledac E/WindowManager﹕ android.view.WindowLeaked: Activity com.example.olda.hledac.vypis has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{41baf8f8 V.E..... R......D 0,0-684,192} that was originally added here
            at android.view.ViewRootImpl.<init>(ViewRootImpl.java:370)
            at      android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
            at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
            at android.app.Dialog.show(Dialog.java:286)
            at com.example.olda.hledac.vypis$VypisUzivatele.onPreExecute(vypis.java:91)
            at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
            at android.os.AsyncTask.execute(AsyncTask.java:535)
            at com.example.olda.hledac.vypis.onCreate(vypis.java:51)
            at android.app.Activity.performCreate(Activity.java:5395)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2248)
            at android.app.ActivityThread.access$800(ActivityThread.java:138)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1199)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5072)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
            at dalvik.system.NativeStart.main(Native Method)

Ckeck if one of your tags (TAG_WP_USERS, TAG_ID...) doesn't exist in json response. You have the result in `Log.d("All Products: ", json.toString());` — Rami, Mar 30 '15 at 14:43
possible duplicate of [How to watch for NullPointerEx in Eclipse using Debbuger Add Watch Expression feature?](http://stackoverflow.com/questions/4809646/how-to-watch-for-nullpointerex-in-eclipse-using-debbuger-add-watch-expression-fe) — Budius, Mar 30 '15 at 15:27
@Rami I tried to find this log Log.d("All Products: ", json.toString()); but it never show in logcat when I debug — Oldřich Barták, Mar 30 '15 at 15:56
this might problem with your dialog, refer this http://stackoverflow.com/questions/19155670/android-error-window-leaked-in-asynctask — Heshan Sandeepa, Mar 30 '15 at 16:12

score 0 · Answer 1 · answered Mar 31 '15 at 08:41

In this case was problem at my webhosting. They include their adverbs on every page and this adverb was sending with JSON and that was the problem and help me this solution. I setup substring and it works now.

try {
        jObj = new JSONObject(json.substring(3));
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data [" + e.getMessage()+"] "+json);
    }

Android doInBackground Fatal expection Asynctask #1

1 Answers1