android - Uncaught Handler error. -

i trying http post , came know time consuming tasks should used within async task or handler, tried code using handler getting handler uncaught exception, unable determine going wrong. below code , log trace.

           @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);       button bt = (button)findviewbyid(r.id.button1);     button btx = (button)findviewbyid(r.id.button2);         et = (edittext)findviewbyid(r.id.edittext1);     etp = (edittext)findviewbyid(r.id.edittext2);      bt.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view v) {             dialog = progressdialog.show(mainactivity.this,"loading", "please wait...");              h = new handler(){                  @override                 public void handlemessage(message msg) {                     super.handlemessage(msg);                     dialog.dismiss();                  }             };               new thread(){                  @override                 public void run() {                     super.run();                      connection();                      try {                         thread.sleep(3000);                         h.sendemptymessage(0);                      } catch (interruptedexception e) {                         e.printstacktrace();                     }                  }              }.start();          }     });              // btx.setonclicklistener(sig);     }          private view.onclicklistener sig =new view.onclicklistener() {         public void onclick(view v){               intent sign = new intent(mainactivity.this,signup.class);             startactivity(sign);          }         };              public  void connection(){     string = null;     string x = et.gettext().tostring();     string y = etp.gettext().tostring();      if(x.length()>0 && y.length()>0){         = x;         b = y;          httpclient httpclient = new defaulthttpclient();         httppost httppost = new httppost("http://animsinc.com/query.php");          try {            list<namevaluepair> namevaluepairs = new arraylist<namevaluepair>(2);            namevaluepairs.add(new basicnamevaluepair("username", x));            namevaluepairs.add(new basicnamevaluepair("password",y));            httppost.setentity(new urlencodedformentity(namevaluepairs));            httpclient.execute(httppost);         //   et.settext(""); // clear text box         //   etp.settext(""); // clear text box          httpresponse responce = httpclient.execute(httppost);         httpentity entity = responce.getentity();         = entityutils.tostring(entity);        // in = entity.getcontent();       //  log.e("post responce----->", "" + is);         toast.maketext(this,""+is, toast.length_long).show();           } catch (clientprotocolexception e) {              // todo auto-generated catch block          }catch (unsupportedencodingexception e) {             e.printstacktrace();          }catch (ioexception e) {              // todo auto-generated catch block          }         } else{             // display message if text fields empty              toast.maketext(getbasecontext(),"all field required",toast.length_short).show();          }     if(is != null){         toast.maketext(this,""+is, toast.length_long).show();      }    } 

}

this log cat:

problem calling:

toast.maketext(this,""+is, toast.length_long).show(); 

from worker thread inside run() method. shouldn't it. can manipulate ui main(ui) thread.

solution use runonuithread() or asynctask or show toast in handler.