Как получить данные в списке с помощью AsyncTask в android?

Question

public class Test2 extends Activity { 

private ListView lv; 
private ImageView logout,leftclosed,rightclosed,back,leftclosedadmin,rightclosedadmin,home; 
private JSONObject json; 
private ArrayList<Object> Item; 
private Context mContext; 
private SharedPreferences mSharedPreferencesWrite; 
private CommonClass mCommonClass = new CommonClass(); 
public String category_name,category_id,product_id,product_name; 
public StockAdapter adapter; 
public ActivityBean bean; 

public void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.xstockdetails); 
    lv=(ListView)findViewById(R.id.stockdetails_listview); 
    lv.setVerticalFadingEdgeEnabled(false); 
    Item=new ArrayList<Object>(); 

    class AsyncLogin extends AsyncTask<Void, Void, String> 
    { 
     ProcessDialog dialog = null; 
     public String doInBackground(Void... params) 
     { 
      try { 
       String strURL = mContext.getResources().getString(
         R.string.STOCK_DETAILS); 
       ArrayList<NameValuePair> mNameValuePair = new ArrayList<NameValuePair>(); 
       mNameValuePair 
         .add(new BasicNameValuePair("action", "getstock")); 
       mNameValuePair.add(new BasicNameValuePair("collection_by", 
         mSharedPreferencesWrite 
           .getString(Constant.LOGIN_SHARED.LS_USERID, "") 
           .toString().trim())); 
       String result = mCommonClass.PostConnection(strURL, 
         mNameValuePair); 
       if (result != null) { 

        try { 
         JSONObject jsonstockdetails = new JSONObject(result); 
         if (jsonstockdetails.getString(
           Constant.COMMON_JSON.TYPE).equals(
           Constant.COMMON_JSON.OK)) { 
          JSONObject jsonReturnResult = jsonstockdetails 
            .getJSONObject("ReturnResult"); 
          // Log.i("Result", "got result" + jsonReturnResult); 
          // Log.i(Constant.TAG,"Return Result :--- "+jsonReturnResult.names().toString()); 
          JSONArray jsonArray = jsonReturnResult.names(); 

          for (int i = 0; i < jsonArray.length(); i++) { 
           JSONObject jsonOBJName = jsonReturnResult 
             .getJSONObject(jsonArray.getString(i) 
               .toString()); 
           Log.i("jsonOBJName", "mil gaye in tesing" 
             + jsonOBJName); 
           category_id = jsonOBJName 
             .getString("category_id"); 
           category_name = jsonOBJName 
             .getString("category_name"); 
           product_id = jsonOBJName 
             .getString("product_id"); 
           product_name = jsonOBJName 
             .getString("product_name"); 
           Log.i("categories", "in testing!!" 
             + category_id + category_name 
             + product_id); 

           AddObjectToList(category_id,category_name,product_id,product_name); 
          } 
         } 
        } catch (Exception e) { 
         e.printStackTrace(); 
        } 

        return result; 
       } 
      } 
      catch(Exception e) 
      { 
       e.printStackTrace(); 
      } 


      return null; 
     } 


     protected void onPostExecute(String result) 
     { 
      dialog.cancel(); 
      adapter=new StockAdapter(Test2.this,Item); 
      lv.setAdapter(adapter); 

     } 


     protected void onPreExecute() 
     { 
      super.onPreExecute(); 
      /*dialog.setMessage("Loading....Please Wait"); 
      dialog.setCancelable(true); 
      dialog.show();*/ 
      dialog = new ProcessDialog(getApplicationContext(), "Loading..", ""); 

     } 
    } 
    if (mCommonClass.CheckNetwork(this)) { 
     AsyncLogin al = new AsyncLogin(); 
     al.execute(); 
    }else{ 
     Log.i("Alert!!!", "Server not Found"); 
    } 
} 
private void AddObjectToList(String category_id,String category_name,String product_id,String product_name) 
{ 

    bean =new ActivityBean(); 
    bean.setCategoryid(category_id); 
    bean.setCategory_name(category_name); 
    bean.setProductId(product_id); 
    bean.setProductName(product_name); 

    Item.add(bean); 
} 
public class StockAdapter extends BaseAdapter{ 

    ArrayList<Object> Aitem; 
    List<ActivityBean> yourList = null; 
    Activity context; 
    LayoutInflater li; 

    public StockAdapter(Activity parent,ArrayList<Object> item){ 
     this.context = parent; 
     this.Aitem = item; 
     this.li=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
    } 

    @Override 
    public int getCount() { 
     // TODO Auto-generated method stub 
     return Aitem.size(); 
    } 

    @Override 
    public Object getItem(int position) { 
     // TODO Auto-generated method stub 
     return Aitem.get(position); 
    } 

    @Override 
    public long getItemId(int position) { 
     // TODO Auto-generated method stub 
     return 0; 
    } 
    class ViewHolder 
     { 
     Button b1,b3,btndelete; 
     TextView tv0,tv1,tv2,tv3; 

     } 

    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 
     // TODO Auto-generated method stub 
     final ViewHolder hv; 
     if(convertView==null) 
     { 
      hv=new ViewHolder(); 
      convertView=li.inflate(R.layout.xstockdetailsadapter,null); 

      hv.tv0 = (TextView) convertView.findViewById(R.id.categoryname_txt); 
      hv.tv1 = (TextView) convertView.findViewById(R.id.textView1); 
      hv.tv2 = (TextView) convertView.findViewById(R.id.textView2); 
      hv.tv3 = (TextView) convertView.findViewById(R.id.textView3); 

      convertView.setTag(hv); 
     }else { 
      hv=(ViewHolder)convertView.getTag(); 
      final ActivityBean ab = (ActivityBean) Aitem.get(position); 

      hv.tv0.setText(ab.getCategory_name()); 
      hv.tv1.setText(ab.getCategoryid()); 
      hv.tv2.setText(ab.getProductId()); 
      hv.tv3.setText(ab.getProductName()); 

     } 
     return convertView; 
    } 

} 
} 

Я использую этот код для получения данных в listview с использованием Asynctask, но я получаю ниже ошибки, может ли кто-нибудь мне помочь? {

08-09 11:59:34.174: E/AndroidRuntime(6180): FATAL EXCEPTION: main 
08-09 11:59:34.174: E/AndroidRuntime(6180): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.ovte.letsrecycle/com.ovte.letsrecycle.Test2}: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread.access$600(ActivityThread.java:141) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.os.Handler.dispatchMessage(Handler.java:99) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.os.Looper.loop(Looper.java:137) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread.main(ActivityThread.java:5041) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at java.lang.reflect.Method.invokeNative(Native Method) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at java.lang.reflect.Method.invoke(Method.java:511) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at dalvik.system.NativeStart.main(Native Method) 
08-09 11:59:34.174: E/AndroidRuntime(6180): Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.view.ViewRootImpl.setView(ViewRootImpl.java:571) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:246) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.Dialog.show(Dialog.java:281) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at com.ovte.letsrecycle.ProcessDialog.<init>(ProcessDialog.java:19) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at com.ovte.letsrecycle.Test2$1AsyncLogin.onPreExecute(Test2.java:143) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.os.AsyncTask.execute(AsyncTask.java:534) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at com.ovte.letsrecycle.Test2.onCreate(Test2.java:149) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.Activity.performCreate(Activity.java:5104) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144) 
08-09 11:59:34.174: E/AndroidRuntime(6180):  ... 11 more 

}

Answer 1

Попробуйте это:

public void onPreExecute() 
    { 
     super.onPreExecute(); 
     dialog = new ProcessDialog(ActivityName.this, "Loading..", ""); 
     dialog.setMessage("Loading....Please Wait"); 
     dialog.setCancelable(true); 
     dialog.show(); 


    }