how to print text message on backgroundtask

Question

below is my complete code which work fine if i m not using public class getDataTask extends AsyncTask<Void, Void, Void>{ } class is show text mesage on else statment but now i want to use progressbar untill server not load problem is if server return data then code work fine if server not return data else statement not work show toast message code is stop unexpectedly what should i do?

     public class SecondStep extends Activity {

ListView listMainMenu;
String SelectMenuAPI;
String SelectMenuAPI2;
String SearchSchoolurl;
String status;
String message;
ProgressBar prgLoading;
TextView txtAlert;

String param1;
String Menu_name;
String School_name;
secondscreenadapter mma;
TextView schoolname;

TextView textview1;
int IOConnect = 0;

static ArrayList<Long> Category_ID = new ArrayList<Long>();
static ArrayList<String> Category_name = new ArrayList<String>();
String URL, URL2, URL3, URL4;
String id;
String title;
String tmpString, finaldate, enddate;
String startdate;
String startdate2;
String val1, val2, val3, val4;
String mode;
String s2;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.secondstep);
    prgLoading = (ProgressBar) findViewById(R.id.prgLoading);
    txtAlert = (TextView) findViewById(R.id.txtAlert);

    s2 = "search";
    mode = HomeMenu.mode;
    if (mode.equals(s2.toString())) {

        Bundle bundle = this.getIntent().getExtras();
        School_name = bundle.getString("Serachvalue");
    } else {
        Bundle bundle = this.getIntent().getExtras();
        School_name = bundle.getString("School_name");
    }

    ImageView options = (ImageView) findViewById(R.id.options2);

    options.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent iMenuList = new Intent(SecondStep.this,
                    LinkButtons.class);
            startActivity(iMenuList);
        }
    });

    ImageView btnback = (ImageView) findViewById(R.id.btnback);

    ImageView logoimage = (ImageView) findViewById(R.id.bitmap);

    logoimage.setScaleType(ScaleType.FIT_CENTER);

    textview1 = (TextView) findViewById(R.id.textview1);
    listMainMenu = (ListView) findViewById(R.id.listMainMenu2);

    mma = new secondscreenadapter(this);
    new getDataTask().execute();

    // listMainMenu.setAdapter(mma);

    textview1
            .setText("If your school is not available in the list,.");

    listMainMenu.setOnItemClickListener(new OnItemClickListener() {

        public void onItemClick(AdapterView<?> arg0, View arg1,
                int position, long arg3) {
            // TODO Auto-generated method stub
    Intent iMenuList = new Intent(SecondStep.this,MealGroups.class);

    iMenuList.putExtra("category_name",  Category_name.get(position));

            iMenuList.putExtra("id", val1);
            iMenuList.putExtra("title", val2);
            iMenuList.putExtra("startdate", val3);
            iMenuList.putExtra("enddate", val4);

            startActivity(iMenuList);

        }
    });

    btnback.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            finish();
        }
    });

    // parseJSONData();
}

void clearData() {
    Category_ID.clear();
    Category_name.clear();

}

public class getDataTask extends AsyncTask<Void, Void, Void> {

    getDataTask() {
        if (!prgLoading.isShown()) {
            prgLoading.setVisibility(0);
            txtAlert.setVisibility(8);

            // count=1;
        }
    }

    @Override
    protected void onPreExecute() {
        // TODO Auto-generated method stub

    }

    @Override
    protected Void doInBackground(Void... arg0) {
        // TODO Auto-generated method stub
        parseJSONData();
        return null;
    }

    @Override
    protected void onPostExecute(Void result) {
        // TODO Auto-generated method stub
        prgLoading.setVisibility(8);

        if ((Category_ID.size() > 0) || IOConnect == 0) {
            listMainMenu.setVisibility(0);
            listMainMenu.setAdapter(mma);
        } else {
            txtAlert.setVisibility(0);
        }
    }
}

public void parseJSONData() {

    mode = HomeMenu.mode;
    if (mode.equals(s2.toString())) {

        SelectMenuAPI = Utils.SearchSchool + School_name;

        clearData();
        URL = SelectMenuAPI;
        URL2 = URL.replace(" ", "%20");

    } else {

        SelectMenuAPI = Utils.Schoolname + School_name;
        clearData();
        URL = SelectMenuAPI;
        URL2 = URL.replace(" ", "%20");
    }

    SelectMenuAPI2 = Utils.getSchedule;

    clearData();
    URL3 = SelectMenuAPI2;
    URL4 = URL3.replace(" ", "%20");

    try {

        HttpClient client = new DefaultHttpClient();
        HttpConnectionParams
                .setConnectionTimeout(client.getParams(), 15000);
        HttpConnectionParams.setSoTimeout(client.getParams(), 15000);
        HttpUriRequest request = new HttpGet(URL2);
        HttpResponse response = client.execute(request);
        InputStream atomInputStream = response.getEntity().getContent();
        BufferedReader in = new BufferedReader(new InputStreamReader(
                atomInputStream));

        String line;
        String str = "";
        while ((line = in.readLine()) != null) {
            str += line;
        }

        HttpClient client2 = new DefaultHttpClient();
        HttpConnectionParams.setConnectionTimeout(client2.getParams(),
                15000);
        HttpConnectionParams.setSoTimeout(client2.getParams(), 15000);
        HttpUriRequest request2 = new HttpGet(URL4);
        HttpResponse response2 = client2.execute(request2);
        InputStream atomInputStream2 = response2.getEntity().getContent();
        BufferedReader in2 = new BufferedReader(new InputStreamReader(
                atomInputStream2));

        String line2;
        String str2 = "";
        while ((line2 = in2.readLine()) != null) {
            str2 += line2;
        }

        JSONObject json2 = new JSONObject(str);

        status = json2.getString("status");
        if (status.equals("1")) {

            JSONArray school = json2.getJSONArray("data");

            for (int i = 0; i < school.length(); i++) {
                JSONObject object = school.getJSONObject(i);

                Category_ID.add(Long.parseLong(object
                        .getString("school_id")));
                Category_name.add(object.getString("name"));

            }

        }

        else {

            mode = HomeMenu.mode;
            if (mode.equals(s2.toString())) {
                textview1
                        .setText("No school found,.");
            } else {
                textview1
                        .setText("No school found in "
                                + School_name
                                + ",.");
            }

        }

        JSONObject json3 = new JSONObject(str2);
        // message = json2.getString("message");
        status = json3.getString("status");
        if (status.equals("1")) {

            JSONArray school = json3.getJSONArray("data");

            for (int k = 0; k < school.length(); k++) {
                JSONObject jb = (JSONObject) school.getJSONObject(k);
                id = jb.getString("schedule_id");
                title = jb.getString("title");

                startdate = jb.getString("start_date");
                tmpString = startdate.replace(" 00:00:00", "");
                finaldate = tmpString.replace("-", "/");
                enddate = jb.getString("end_date");

            }

            val1 = id;
            val2 = title;
            val3 = finaldate;
            val4 = enddate;

        }

        else {

            JSONArray school1 = json3.getJSONArray("data");
            for (int i = 0; i < school1.length(); i++) {
                JSONObject object = school1.getJSONObject(i);

                Category_ID.add((long) i);
                Category_name.add(object.getString("name"));

            }

        }

    } catch (MalformedURLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        IOConnect = 1;
        e.printStackTrace();
    } catch (JSONException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

 }

My Logcat is:

        AndroidRuntime(574): FATAL EXCEPTION: AsyncTask #4
   AndroidRuntime(574): java.lang.RuntimeException: An error occured while executing  
  doInBackground()

 AndroidRuntime(574):   at android.os.AsyncTask$3.done(AsyncTask.java:200)
  AndroidRuntime(574):  at   
 java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
  AndroidRuntime(574):  at 
  java.util.concurrent.FutureTask.setException(FutureTask.java:124)
 AndroidRuntime(574):   at 
java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
 AndroidRuntime(574): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
 AndroidRuntime(574):at    
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
AndroidRuntime(574):    at   
 java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
    AndroidRuntime(574):    at java.lang.Thread.run(Thread.java:1096)
 AndroidRuntime(574): Caused by: android.view.ViewRoot$CalledFromWrongThreadException:  
  Only     the original thread that created a view hierarchy can touch its views.
  AndroidRuntime(574): at android.view.ViewRoot.checkThread(ViewRoot.java:2802)
 AndroidRuntime(574):at android.view.ViewRoot.requestLayout(ViewRoot.java:594)
 0AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
  AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
  AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
   AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
  AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
  AndroidRuntime(574):at android.view.View.requestLayout(View.java:8125)
  0AndroidRuntime(574):at android.widget.TextView.checkForRelayout(TextView.java:5378)
 AndroidRuntime(574):at android.widget.TextView.setText(TextView.java:2688)
 AndroidRuntime(574):at android.widget.TextView.setText(TextView.java:2556)
 AndroidRuntime(574):at android.widget.TextView.setText(TextView.java:2531)
 AndroidRuntime(574):at com.schoollunchapp.SecondStep.parseJSONData(SecondStep.java:281)
AndroidRuntime(574):at    
  com.schoollunchapp.SecondStep$getDataTask.doInBackground(SecondStep.java:177)
  AndroidRuntime(574):  at    
  com.schoollunchapp.SecondStep$getDataTask.doInBackground(SecondStep.java:1)
  AndroidRuntime(574):  at android.os.AsyncTask$2.call(AsyncTask.java:185)
    AndroidRuntime(574):    at     
  java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)

inmethod parseJSONData(); else statement not show textview message code stop unexpectedly — user2778836, Sep 17 '13 at 06:52

score 0 · Answer 1 · edited May 23 '17 at 12:28

0

You are updating ui from a background thread which is not possible.

textview1.setText("No school found");

You need to update ui on the ui thread. Do it in onPostExecute

Return result of the background computation in doInbackground. The result of doInbackground computation is a param to onPostExecute. So based on the result update ui in onPostExecute.

You can also use runOnUiThread which is a method of activity class.

If your asynctask is not an inner class of your activity you can use interface

Can't post response from AsyncTask to MainActivity

edited May 23 '17 at 12:28

Community

1
1

answered Sep 17 '13 at 06:57

Raghunandan

132,755
26
225
256

but how do i check which message show there is two textview message which check first mode = HomeMenu.mode; if (mode.equals(s2.toString())) { – user2778836 Sep 17 '13 at 06:58
return the mode in doinbackground check and update textview in onPostexcute – Raghunandan Sep 17 '13 at 07:00
@user2778836 i suggest you read the docs has an example and details you need http://developer.android.com/reference/android/os/AsyncTask.html – Raghunandan Sep 17 '13 at 07:08

Harish Godara · Answer 2 · 2013-09-17T07:04:47.900

0

You have to use runOnUiThead() like below in your worker thread :

mode = HomeMenu.mode;

runOnUiThread(new Runnable() 
{
    public void run() 
    {
        if (mode.equals(s2.toString())) 
        {
            textview1.setText("No school found,.");
        } 
        else 
        {
            textview1.setText("No school found in " + School_name + ",.");
        }           
    }
});

edited Sep 17 '13 at 07:04

answered Sep 17 '13 at 06:58

Harish Godara

2,388
1
14
28

but checkmy code i apply condtions mode = HomeMenu.mode; if (mode.equals(s2.toString())) { show diffrent textview else show another textview – user2778836 Sep 17 '13 at 07:00
where i placerunOnUiThread(new Runnable() ? at the last of Activity?? – user2778836 Sep 17 '13 at 07:01
u mean add conditions in runonUithread?? whrere i place this piece of code? – user2778836 Sep 17 '13 at 07:03
just only tell me where i place this all runonUitheard code? inside main clas or last of the application code? – user2778836 Sep 17 '13 at 07:06
and how do i identify code goes on else statement in parseJSONData(); method?? – user2778836 Sep 17 '13 at 07:07
For that you have to debug your code I have answered your main question – Harish Godara Sep 17 '13 at 07:09

Tarsem Singh · Accepted Answer · 2013-09-17T09:33:19.347

-1

You are trying to update UI part in doInBackground() of AsyncTask which is not allowed directly

Check Following inside parseJSONData() which is called from doInBackground()

 if (mode.equals(s2.toString())) {
        textview1.setText("No school found,.");
    } else {
        textview1.setText("No school found in "+ School_name+ ",.");
    }

if you are to update the UI part do same in onPostExecute() of AsyncTask

edited Sep 17 '13 at 09:33

answered Sep 17 '13 at 06:57

Tarsem Singh

14,139
7
51
71

so how do i show this messages in background therad with conditions? if mode.equals(S2.String); – user2778836 Sep 17 '13 at 06:59
@user2778836 do same in `onPostExecute() of AsyncTask`, would be much better than using anything else. – Tarsem Singh Sep 17 '13 at 07:03
but how do i indicate from onpostexecute from inside parseJSONData() that now show this toast message? – user2778836 Sep 17 '13 at 07:10
`onPostExecute` is better , change the return types in `Aynctask` and of the method parseJSONData and also `doinbackground` make it to return string and in `onPostExecute` check the condition with result. – Rahul Patil Sep 17 '13 at 09:55
@Tarsem , I am not the one who did a down vote . I just expressed by concern – Rahul Patil Sep 17 '13 at 11:03

how to print text message on backgroundtask

3 Answers3