<?php
try{
$usuario = "ABCDEFGHIJKLM";
$password = "1234567890";
$conn = new PDO('mysql:host=fdb3.runhosting.com;dbname=DataBaseName', $usuario, $password);
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}catch(PDOException $e){
 echo "ERROR: " . $e->getMessage();
}
 $user=$_POST['user'];
 $Pass=$_POST['Pass'];
 $TipoUsuario=$_POST['$TipoUsuario'];
 $Code=$_GET['Code'];
$sql="UPDATE Usuarios SET user=?,Pass=?,TipoUsuario=? WHERE Code =?";
$stp=$conn->prepare($sql);
$pdoexect=$stp->execute(array($user,$Pass,$TipoUsuario,$Code));
if($pdoexect)
{
  echo "Actualización exitosa";
}else{
    echo "no se  pudo actualizar";
 }

?>

private void updateUsuario(){

 final String Code = et1.getText().toString().trim();
 final String User = et2.getText().toString().trim();
 final String Pass = et3.getText().toString().trim();
 final  String TipoUsuario=tipUser.getSelectedItem().toString();

 class UpdateUsuario extends AsyncTask<Void,Void,String>{
     ProgressDialog loading;
     @Override
     protected void onPreExecute() {
         super.onPreExecute();
         loading = ProgressDialog.show(buscarUpdateUser.this,"Updating...","Wait...",false,false);
     }

     @Override
     protected void onPostExecute(String s) {
         super.onPostExecute(s);
         loading.dismiss();
         Toast.makeText(buscarUpdateUser.this,s,Toast.LENGTH_LONG).show();
     }

     @Override
     protected String doInBackground(Void... params) {
         HashMap<String,String> hashMap = new HashMap<>();
         hashMap.put(Config.KEY_USER_CODE,Code);
         hashMap.put(Config.KEY_USER_USUARIO,User);
         hashMap.put(Config.KEY_USER_PASS,Pass);
         hashMap.put(Config.KEY_USER_TIPOUSER,TipoUsuario);

         RequestHandler rh = new RequestHandler();

         String s = rh.sendPostRequest(Config.URL_UPDATE_USER,hashMap);
         return s;
     }
 }
 UpdateUsuario ue = new UpdateUsuario();
 ue.execute();
 }