connection - Android app on real device,crashes when try connecting to server -

i trying run simple android code on real device keeps crashing, works fine on emulator.

my code

 package com.example.new1;        import java.io.bufferedreader;      import java.io.inputstreamreader;      import java.net.httpurlconnection;      import java.net.url;      import android.os.asynctask;      import android.os.bundle;      import android.app.activity;      import android.view.menu;      import android.view.view;      import android.widget.textview;       public class mainactivity extends activity {      textview tx;     @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);         tx= (textview)findviewbyid(r.id.text);     }      public void func(view view)     {         //tx.settext("working fine till here.");          new fetchsql().execute();     }      @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.activity_main, menu);         return true;     }     private class fetchsql  extends asynctask<string,void,string>      {             @override         protected string doinbackground(string... arg0) {                 url url = null;                 bufferedreader reader = null;                 stringbuilder stringbuilder;                 string myurl = "http://10.22.35.4:80/conc2.php";             try             { url =new url(myurl);               httpurlconnection connection = (httpurlconnection)      url.openconnection();               connection.setrequestmethod("get");               connection.setreadtimeout(15*10000);               connection.connect();               reader = new bufferedreader(new inputstreamreader(connection.getinputstream()));               stringbuilder = new stringbuilder();               string line = null;               while ((line = reader.readline()) != null)               {                 stringbuilder.append(line + "\n");                }             // todo auto-generated method stub             return stringbuilder.tostring();             }             catch(exception e)             {                 tx.settext(e.tostring());             }             return null;         }           protected void onpostexecute(string result)         {              tx.settext(result);         }       } } 

it works fine on emulator , output gives

v. m. aroradr. c. p. reddyarti chowdharyjagdish singh on running same on device. gives following error code.

05-03 11:49:39.002: e/androidruntime(19934): fatal exception: asynctask #1 05-03 11:49:39.002: e/androidruntime(19934): java.lang.runtimeexception: error occured while executing doinbackground() 05-03 11:49:39.002: e/androidruntime(19934):    @    android.os.asynctask$3.done(asynctask.java:200) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.futuretask$sync.innersetexception(futuretask.java:273) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.futuretask.setexception(futuretask.java:124) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.futuretask$sync.innerrun(futuretask.java:307) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.futuretask.run(futuretask.java:137) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1068) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:561) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.lang.thread.run(thread.java:1096) 05-03 11:49:39.002: e/androidruntime(19934): caused by: android.view.viewroot$calledfromwrongthreadexception: original thread created view hierarchy can touch views. 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.viewroot.checkthread(viewroot.java:2811) 05-03 11:49:39.002: e/androidruntime(19934):    @   android.view.viewroot.requestlayout(viewroot.java:594) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.view.requestlayout(view.java:8180) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.view.requestlayout(view.java:8180) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.view.requestlayout(view.java:8180) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.view.requestlayout(view.java:8180) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.widget.relativelayout.requestlayout(relativelayout.java:257) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.view.view.requestlayout(view.java:8180) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.widget.textview.checkforrelayout(textview.java:5383) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.widget.textview.settext(textview.java:2688) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.widget.textview.settext(textview.java:2556) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.widget.textview.settext(textview.java:2531) 05-03 11:49:39.002: e/androidruntime(19934):    @ com.example.new1.mainactivity$fetchsql.doinbackground(mainactivity.java:66) 05-03 11:49:39.002: e/androidruntime(19934):    @ com.example.new1.mainactivity$fetchsql.doinbackground(mainactivity.java:1) 05-03 11:49:39.002: e/androidruntime(19934):    @ android.os.asynctask$2.call(asynctask.java:185) 05-03 11:49:39.002: e/androidruntime(19934):    @ java.util.concurrent.futuretask$sync.innerrun(futuretask.java:305) 05-03 11:49:39.002: e/androidruntime(19934):    ... 4 more 

please help, how run stupid code on real device. ive got device

gti-9003 , android 2.2.1 (froyo).. , in app i've put min sdk ..of 1.5(cupcake).

its because trying change ui, settext actually, in doinbackground method not meant ui tasks.

here:

catch(exception e)             {                 tx.settext(e.tostring());             } 

you can this:

catch(exception e)             {                 return e.tostring();             } 

and in onpostexecute, set text textview.