android app inserts blank row instead of value - php

Question

my code inserts an empty field when i try to run it from the android emulator.
the php script is fine, when i replace the variables with actual values it works.
when i run the script itself, it sends a row to my database, which is 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'];
$query="INSERT INTO name (username, password) VALUES ('$username' ,'$password')";
$res = mysql_query($query) or die ("Error: ". mysql_error(). " with query ");
mysql_close($connect);
echo $res;
?>
this is my java code, which can't connect to my php script.
when i run this 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();
}
}
});
}