How to Display json array to listview with AsyncTask?

Question

Hello I am new for the android,so please let me know where I am wrong.

I want convert the jsonarray into custom listview.I tried much but I don't get the solution. I got the value that I want into strValue1(please check the below code ,Activites_Activity.java). Now ,I want to pass this strValue1 into the listview. but I am not able to convert it into listview.

so Please let me know what i should do?

I got the error

04-17 12:52:55.795: E/AndroidRuntime(765): FATAL EXCEPTION: AsyncTask #1
04-17 12:52:55.795: E/AndroidRuntime(765): java.lang.RuntimeException: An error occured               while executing doInBackground()
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.os.AsyncTask$3.done(AsyncTask.java:200)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.lang.Thread.run(Thread.java:1096)
04-17 12:52:55.795: E/AndroidRuntime(765): Caused by: android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewRoot.checkThread(ViewRoot.java:2802)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewRoot.focusableViewAvailable(ViewRoot.java:1596)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:451)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.View.setFlags(View.java:4474)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.view.View.setFocusableInTouchMode(View.java:3104)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.widget.AdapterView.checkFocus(AdapterView.java:694)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.widget.ListView.setAdapter(ListView.java:437)
04-17 12:52:55.795: E/AndroidRuntime(765):  at com.rahul.cheerfoolz.activites.Activites_Activity$activites.doInBackground(Activites_Activity.java:141)
04-17 12:52:55.795: E/AndroidRuntime(765):  at com.rahul.cheerfoolz.activites.Activites_Activity$activites.doInBackground(Activites_Activity.java:1)
04-17 12:52:55.795: E/AndroidRuntime(765):  at android.os.AsyncTask$2.call(AsyncTask.java:185)
04-17 12:52:55.795: E/AndroidRuntime(765):  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
04-17 12:52:55.795: E/AndroidRuntime(765):  ... 4 more

Thanks.

Activites_Activity.java

public class Activites_Activity extends CheerfoolznativeActivity {

 TextView txtactivity;
 ListView list;
 LazyAdapter adapter;
 ImageView img;
 ProgressBar pgb;

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

    setContentView(R.layout.activity_activites);
    setHeader("Activites");

/*
     list=(ListView)findViewById(R.id.activity_listView);
    adapter=new LazyAdapter(this, mImages,mTitle);
    list.setAdapter(adapter);
*/
    txtactivity = (TextView) findViewById(R.id.activity_textView);
    img=(ImageView)findViewById(R.id.activity_image);
    pgb = (ProgressBar)findViewById(R.id.activity_progressBar);
    new activites().execute();
}

public class activites extends AsyncTask<Void, Void, Void> {
    String parsedString = "\n";  
    String strValue1 ;
    public int i=0;

    @Override
    protected void onPreExecute() {
        // TODO Auto-generated method stub
        super.onPreExecute();
         pgb.setVisibility(View.VISIBLE);
    }

    @Override
    protected Void doInBackground(Void... params) {
        // TODO Auto-generated method stub
        String url = " Here my json URL ";

        String strResponse = util.makeWebCall(url);

        try {
            JSONObject objResponse = new JSONObject(strResponse);

            JSONArray jsonnodes = objResponse.getJSONArray(API.cheerfoolz_activities.NODES);
            Log.i(" NO of entries===>" +Activites_Activity.class.getName(),"Number of entries " + jsonnodes.length());

            ArrayList<String> items = new ArrayList<String>();

            for (i = 0; i < jsonnodes.length(); i++) 
            {
                String str = Integer.toString(i); 
                Log.i("Value of i",str);

                JSONObject jsonnode = jsonnodes.getJSONObject(i); 

                JSONObject jsonnodevalue = jsonnode.getJSONObject(API.cheerfoolz_activities.NODE);

                strValue1 = jsonnodevalue.getString(API.cheerfoolz_activities.TITLE);

                Log.i("JSONArray", strValue1);
                //parsedString += " \n\n Value of stored parse :  => " + strValue1;
                parsedString = parsedString.trim(); //this will remove the blank white space

                items.add(strValue1);

                parsedString += " \n Value added in list  => " + items;

                Log.i("Value of items : ", parsedString);



            }


            //List<String> list = Arrays.asList((String[])jsonnodes.toString());
            //String[] values= new String[]{items.toString()};
            //myListView.setListAdapter(

            /* list=(ListView)findViewById(R.id.activity_listView);
               // adapter=new LazyAdapter((Activity) getApplicationContext(), mImages,mTitle);
                list.setAdapter(adapter);*/

            ListView myListView = (ListView)findViewById(R.id.activity_listView);
            myListView.setAdapter(new ArrayAdapter(getApplicationContext(), android.R.layout.simple_expandable_list_item_1, items));

    //      ArrayAdapter<String> adapter= new ArrayAdapter<String>(Activites_Activity.this, android.R.layout.simple_list_item_1,items);
    //      myListView.setAdapter(adapter);
            //Log.i("contact", items1 );

        }
        catch (JSONException e) {

            e.printStackTrace();
            txtactivity.setText(e.getMessage());

        }

        return null;
    }

    @Override
    protected void onProgressUpdate(Void... values) {
        // TODO Auto-generated method stub
        super.onProgressUpdate(values);
    }

    @Override
    public void onPostExecute(Void result) {
        // TODO Auto-generated method stub
        super.onPostExecute(result);

        txtactivity.setText(parsedString);
        pgb.setVisibility(View.GONE);
        //img.setImageResource(parsedString);
    }
}

}

LazyAdapter.java

public class LazyAdapter extends BaseAdapter{

private Activity context;
private String[] title;
private String[] images;
private LayoutInflater inflater;


public LazyAdapter(Activity context,String[] img ,String[] title) {  
    super();  

    this.context = context;  
    this.title = title;  
    this.images = img; 

    this.inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);  
}  

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

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

@Override  
public long getItemId(int position) {  
    // TODO Auto-generated method stub  
    return 0;  
}  

public static class ViewHolder  
{  
    ImageView imgViewLogo;  
    TextView txtViewTitle;  

}  

@Override  
public View getView(int position, View convertView, ViewGroup parent) {  
    // TODO Auto-generated method stub  

    ViewHolder holder;  
    if(convertView==null)  
    {  
        holder = new ViewHolder();  
        convertView = inflater.inflate(R.layout.activity_listitem, null);  

        holder.imgViewLogo = (ImageView) convertView.findViewById(R.id.activity_list_logo);  
        holder.txtViewTitle = (TextView) convertView.findViewById(R.id.activity_list_title);  

        convertView.setTag(holder);  
    }  
    else  
        holder=(ViewHolder)convertView.getTag();  

 //  holder.imgViewLogo.setImageResource(images[position]);  
    holder.txtViewTitle.setText(title[position]);  


    return convertView;  
}   

}

makeWebCall.class

public static String makeWebCall(String url) {

    DefaultHttpClient client = new DefaultHttpClient();

    HttpGet httpRequest = new HttpGet(url);

    try {

        HttpResponse httpResponse = client.execute(httpRequest);

         final int statusCode = httpResponse.getStatusLine().getStatusCode();

         if (statusCode != HttpStatus.SC_OK) {
          /*  Log.i(getClass().getSimpleName(),
                "Error => " + statusCode + " => for URL " + url);*/
            return null;
         }

         HttpEntity entity = httpResponse.getEntity();
            InputStream is = entity.getContent();
            return iStream_to_String(is);
    }
    catch (IOException e) {
        httpRequest.abort();
      // Log.w(getClass().getSimpleName(), "Error for URL =>" + url, e);
    }

    return null;

 }


public static String iStream_to_String(InputStream is1)
{
     BufferedReader rd = new BufferedReader(new InputStreamReader(is1), 4096);
     String line;
     StringBuilder sb =  new StringBuilder();
     try {
        while ((line = rd.readLine()) != null) {
                sb.append(line);
         }
         rd.close();

    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
     String contentOfMyInputStream = sb.toString();
     return contentOfMyInputStream;
}

Answer 1

Assuming your ListView modifications are right, then move this code:

ListView myListView = (ListView)findViewById(R.id.activity_listView);
            myListView.setAdapter(new ArrayAdapter(getApplicationContext(), android.R.layout.simple_expandable_list_item_1, items));

from the AsyncTask 's doInBackground method into the onPostExecute function. You can't modify any View s from inside doInBackground , you must do it in one of the callback functions that are guaranteed to be run on the event dispatch thread.