php - android app inserts blank row instead of value -

my code inserts empty field when try run android emulator.

the php script fine, when replace variables actual values works.

when run script itself, sends row database, blank.

<?php $connect = mysql_connect("localhost","","") or die(mysql_error()); mysql_select_db("tedd_fyp") or die(mysql_error()); $username = $_post['username']; $password = $_post['password'];   $query="insert name (username, password) values ('$username' ,'$password')";  $res = mysql_query($query) or die ("error: ". mysql_error(). " query ");  mysql_close($connect);  echo $res; ?> 

this java code, can't connect php script.

when run script, nothing happens.

      setcontentview(r.layout.activity_main);        edittext1 = (edittext) findviewbyid(r.id.edittext1);       edittext2 = (edittext) findviewbyid(r.id.edittext2);       button registerlecturer=(button)findviewbyid(r.id.button1);      registerlecturer.setonclicklistener(new view.onclicklistener() {       public void onclick(view v) {      // todo auto-generated method stub            string username = edittext1.gettext().tostring();           string password = edittext2.gettext().tostring();            try          {          defaulthttpclient httpclient = new defaulthttpclient();         httppost httppost = new httppost("http://tedd.5gbfree.com/insert.php");            arraylist<namevaluepair> namevaluepairs = new arraylist<namevaluepair>();              namevaluepairs.add(new basicnamevaluepair("username", username));              namevaluepairs.add(new basicnamevaluepair("password", password));            httppost.setentity(new urlencodedformentity(namevaluepairs));          httpresponse response = httpclient.execute(httppost);           }          catch(exception e)          {          e.printstacktrace();          }      }      });       }