İ m not understand this wrong? [duplicate]

This question already has an answer here:

• Activity has leaked window that was originally added 28 answers

package com.omerta.myapplication;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class Kayit extends Activity {
  Button kayit;
  EditText isim_edit, mail_edit, sifre_edit, sifre_tekrar_edit, telefon_edit;
  String isim, mail, sifre, sifre_tekrar, hata_mesaji, telefon = "";
  boolean hata = false;
  PostClass post = new PostClass();
  String URL_POST = "brdbrmysqlvr.esy.es/kayit.php";
  JSONObject cevap = null;

  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.kayit);


    kayit = (Button) findViewById(R.id.kayit);
    isim_edit = (EditText) findViewById(R.id.editText1);
    mail_edit = (EditText) findViewById(R.id.editText2);
    sifre_edit = (EditText) findViewById(R.id.editText3);
    sifre_tekrar_edit = (EditText) findViewById(R.id.editText4);
    telefon_edit = (EditText) findViewById(R.id.editText5);

    kayit.setOnClickListener(new View.OnClickListener() { //Kay�t ol butonuna t�klan�nca

      @
      Override
      public void onClick(View v) {
        // TODO Auto-generated method stub
        //Edittextlerden bilgileri ald�k
        isim = isim_edit.getText().toString();
        mail = mail_edit.getText().toString();
        sifre = sifre_edit.getText().toString();
        sifre_tekrar = sifre_tekrar_edit.getText().toString();
        telefon = telefon_edit.getText().toString();
        int sifre_karakter = sifre.length();

        if (isim.matches("") || mail.matches("") || sifre.matches("") || sifre_tekrar.matches("")) { // bo� veri var m� kontrol�
          hata = true;
          hata_mesaji = "Gerekli Alanlar� Doldurunuz!!!";
        } else if (!sifre.matches(sifre_tekrar)) { //�ifreler uyu�uyor mu kontrol�
          hata = true;
          hata_mesaji = "�ifreler Farkl�!!!";
        } else if (sifre_karakter < 6) { //�ifre karakter say�s� kontrol�
          hata_mesaji += "�ifre 6 Karakterden Az Olamaz!!!";
          hata = true;
        } else if (!Fonksiyonlar.isEmailValid(mail)) { //Mail format kontrol
          hata_mesaji += "Yanl�� e-mail format�!!!";
          hata = true;
        }

        if (hata) { //hata varsa hatay� alertDialog ile g�steriyoruz
          AlertDialog alertDialog = new AlertDialog.Builder(Kayit.this).create();
          alertDialog.setTitle("Hata");
          alertDialog.setMessage(hata_mesaji);
          alertDialog.setCancelable(false);
          alertDialog.setButton(RESULT_OK, "Tamam", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
              sifre_edit.setText("");
              sifre_tekrar_edit.setText("");
              hata_mesaji = "";
              hata = false;
            }
          });
          alertDialog.show();
        } else { //hata yoksa
          new KayitOl().execute(); //Kay�tOl asynctask class� cag�r�yoruz
        }
      }
    });


  }

  class KayitOl extends AsyncTask < Void, Void, Void > {
    private String sonucmesaji, sonuc, tarih;
    ProgressDialog pDialog;

    protected void onPreExecute() {
      //  progress dialog 
      pDialog = new ProgressDialog(Kayit.this);
      pDialog.setMessage("Kay�t ��leminiz Ger�ekle�tiriliyor...");
      pDialog.setIndeterminate(true);
      pDialog.setCancelable(false);
      pDialog.show();
    }

    protected Void doInBackground(Void...unused) {

        sifre = Fonksiyonlar.sha1(sifre); //�ifreyi sha1 ile �ifreledik

        //Parametreleri ekliyoruz
        List < NameValuePair > params = new ArrayList < NameValuePair > ();
        params.add(new BasicNameValuePair("isim", isim));
        params.add(new BasicNameValuePair("mail", mail));
        params.add(new BasicNameValuePair("sifre", sifre));
        params.add(new BasicNameValuePair("telefon", telefon));

        //Tarih bilgisini almak i�in 
        Calendar c = Calendar.getInstance();
        SimpleDateFormat format = new SimpleDateFormat("dd-MMM-yyyy");
        tarih = format.format(c.getTime());

        String json = post.httpPost(URL_POST, "POST", params, 20000);

        Log.d("Gelen Json", "" + json); //Gelen veriyi logluyoruz.Log Catten kontrol edebiliriz
        try {

          cevap = new JSONObject(json);
          sonucmesaji = cevap.getString("sonucmesaji");

          if (cevap.getString("sonuc") != null) {
            sonuc = cevap.getString("sonuc");
            if (Integer.parseInt(sonuc) == 1) { //E�er kay�t ba�ar�l� ise
              //Sqlite database baglan�p gerekli verileri kaydediyoruz. 
              Database db = new Database(getApplicationContext());
              db.resetTables();
              db.kullaniciEkle(mail, sifre, tarih); //kullan�c�y� ekliyoruz.Ve Main activitye y�nlendiriyoruz.          

              //Sonuc ba�ar�l� ise main activitye y�nlendirdk.
              Intent anasayfa = new Intent(getApplicationContext(), MainActivity.class);
              startActivity(anasayfa);
              finish();

            }
          }

        } catch (JSONException e) {
          e.printStackTrace();
        }
        return null;
      }
      // Sonu� ba�ar�l� ise bu kod �al��m�cak ��nk� Main activitye y�nlenmi� durumda
    protected void onPostExecute(Void unused) {
      // closing progress dialog
      if (pDialog != null) {
        pDialog.dismiss();
        pDialog = null;
      }
      // updating UI from Background Thread
      runOnUiThread(new Runnable() {
        public void run() {
          if (Integer.parseInt(sonuc) == 0) { // Sonu� ba�ar�l� de�il ise 
            AlertDialog alertDialog = new AlertDialog.Builder(Kayit.this).create();
            alertDialog.setTitle("Hata");
            alertDialog.setMessage(sonucmesaji); //Sonuc mesaj�yla bilgilendiriyoruz.
            alertDialog.setCancelable(false);
            alertDialog.setButton(RESULT_OK, "Tamam", new DialogInterface.OnClickListener() {
              public void onClick(DialogInterface dialog, int which) {
                sifre_edit.setText("");
                sifre_tekrar_edit.setText("");
              }
            });
            alertDialog.show();
          }
        }


      });
    }
  }

}

Stack Trace

06-16 01:39:05.405 11493-11493/com.omerta.myapplication E/WindowManager: android.view.WindowLeaked: Activity com.omerta.myapplication.Kayit has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{fa7f0cf V.E..... R......D 0,0-1002,348} that was originally added here
     at android.view.ViewRootImpl.<init>(ViewRootImpl.java:465)
     at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:277)
     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
     at android.app.Dialog.show(Dialog.java:312)
     at com.omerta.myapplication.Kayit$KayitOl.onPreExecute(Kayit.java:104)
     at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
     at android.os.AsyncTask.execute(AsyncTask.java:535)
     at com.omerta.myapplication.Kayit$1.onClick(Kayit.java:86)
     at android.view.View.performClick(View.java:5181)
     at android.view.View$PerformClick.run(View.java:20887)
     at android.os.Handler.handleCallback(Handler.java:739)
     at android.os.Handler.dispatchMessage(Handler.java:95)
     at android.os.Looper.loop(Looper.java:145)
     at android.app.ActivityThread.main(ActivityThread.java:5942)
     at java.lang.reflect.Method.invoke(Native Method)
     at java.lang.reflect.Method.invoke(Method.java:372)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400)
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195)