How to populate the spinner with the dynamic data coming from sql server 2008

Question

I am making an android application in which I want to populate a spinner with an array of string values, coming from SQLServer 2008. I am having a problem in which it says that the spinner cannot be populated from a thread different from the main thread.

       Thread waitth = new Thread() {
         public void run() {
             try {
                    System.out.println("3");

                 String details="mani";
                        System.out.println("4");
                        URLConnection con = getServletConnection();
                        System.out.println("5");
                        ObjectOutputStream oos = new ObjectOutputStream(con.getOutputStream());
                        System.out.println("7");
                        oos.writeObject(details);
                        System.out.println("8");
                        oos.flush();
                        oos.close();
                        // receive result from servlet
                        InputStream inputStream = con.getInputStream();
                        ObjectInputStream inputFromServlet = new ObjectInputStream(
                                inputStream);
                        result = (String[]) inputFromServlet.readObject();
                        //System.out.println(result);
                        inputFromServlet.close();
                        inputStream.close();
                        System.out.println();
                        System.out.println("got it");

                    System.out.println("450200");


                    ArrayList<String> aus=new ArrayList<String>();
                    for(int i=0;i<result.length;i++)
                    aus.add(result[i]);
                 ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, aus);
                    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                   s1=(Spinner)findViewById(R.id.spinner1);

                        s1.setAdapter(adapter);




             }  
            catch (Exception ex) {
              ex.printStackTrace();
            }
         }
            };
            waitth.start();


    }


    private URLConnection getServletConnection() throws MalformedURLException,
       IOException {
    URL urlServlet = new URL("http://ipaddress/spinnerfordata");//servlet
    URLConnection con = urlServlet.openConnection();
    con.setUseCaches (false); 
       con.setDefaultUseCaches(false);
    con.setDoInput(true);
    con.setDoOutput(true);
    con.setUseCaches(false);
    con.setRequestProperty("Content-Type","application/x-java-serialized-object");
    System.out.println("9");
    return con;

  }

Logcat error:

      08-02 18:49:08.439: W/System.err(918):                      android.view.ViewRootImpl$CalledFromWrongThreadException  : Only the original thread that created a view hierarchy can touch its views.
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:4746)
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewRootImpl.focusableViewAvailable(ViewRootImpl.java:2588)
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
08-02 18:49:08.454: W/System.err(918):  at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
08-02 18:49:08.454: W/System.err(918):  at android.view.View.setFlags(View.java:8412)
08-02 18:49:08.464: W/System.err(918):  at android.view.View.setFocusable(View.java:5769)
08-02 18:49:08.464: W/System.err(918):  at android.widget.AdapterView.checkFocus(AdapterView.java:718)
08-02 18:49:08.464: W/System.err(918):  at android.widget.AbsSpinner.setAdapter(AbsSpinner.java:115)
08-02 18:49:08.464: W/System.err(918):  at android.widget.Spinner.setAdapter(Spinner.java:380)
08-02 18:49:08.464: W/System.err(918):  at com.example.manispinner.MainActivity$1.run(MainActivity.java:73)

also i am started to think that is this thread necessary for networking with sqlserver 2008? suggest alternatives if there are plzz.... — user2643603, Aug 04 '13 at 22:19

score 0 · Answer 1 · answered Aug 02 '13 at 18:50

0

you are trying to update the UI from a non-UI thread, you cannot do that as the error says. anything relating to the UI needs to be done on the UI thread

answered Aug 02 '13 at 18:50

tyczj

71,600
54
194
296

look up how to use an AsyncTask and then after the task is done in your `onPostExecute` method which runs on the UI thread is where you update – tyczj Aug 02 '13 at 19:12
could u plz give me an example for that,,thnx in advance – user2643603 Aug 02 '13 at 19:31
return the array list you created in your `doInBackground` and you will have your list in the `onPostExecute` or create a global variable in your class and just access it that way – tyczj Aug 02 '13 at 19:51
it seems it doesn't recognise the array result in postexecute() method and this time i am returning the array from doInbackground() method but still result array is not recognised – user2643603 Aug 02 '13 at 20:16
oh god!! i think i just find out what i have to do to make the result array scope valid outside the thread,it was very silly and i doesn't have to make an async task as mentioned by u sir,but the help given by u is very very appreciated!!,,thnx.. – user2643603 Aug 03 '13 at 13:53
sir now i want to ask one more question,how can i make two threads synchronizable such that if one thread can't work until second runs and vice -versa – user2643603 Aug 04 '13 at 22:15

VenomVendor · Accepted Answer · 2013-08-02T20:46:35.197

0

Get the data using an API, from the server, either xml or json
Parse the data.
store it in an array.
```
Do all the above in AsyncTask.
```
Finally populate it to the spinner.

Find an example project at GitHub Spinner-Dynamic

edited Aug 02 '13 at 20:46

answered Aug 02 '13 at 18:59

VenomVendor

15,064
13
65
96

i am using a servlet and i am getting a string from my sqlserver2008 from servlet but the array is not populating in the spinner,could u suggest how can i do that?? – user2643603 Aug 02 '13 at 19:14
You are populating the spinner in the background thread. Populate after finishing the thread. – VenomVendor Aug 02 '13 at 19:19
if i am populating the thread after finishing the thread then the array result scope is gone,,what should i do? – user2643603 Aug 02 '13 at 19:22
Declare your array as a global variable, at the top of your program :) – VenomVendor Aug 02 '13 at 19:41
i did that already but the values which comes from database are gone once i am out of the scope of my waitth thread – user2643603 Aug 02 '13 at 19:51
will give you an simple example, give me few mins – VenomVendor Aug 02 '13 at 19:55
Please check my Updated Answer, this code is very old(2years). Just use this as reference. – VenomVendor Aug 02 '13 at 20:44
sir now i want to ask one more question,how can i make two threads synchronizable such that if one thread can't work until second runs and vice -versa – user2643603 Aug 04 '13 at 22:08
I can't get you, can you be more specific. STOP USING 'SIR'. – VenomVendor Aug 05 '13 at 01:48

How to populate the spinner with the dynamic data coming from sql server 2008

2 Answers2