public class BackgroundWorker extends AsyncTask {
    Context context;
    BackgroundWorker (Context context){
        this.context=context;
    }

    @Override
    protected Object doInBackground(Object[] objects) {
        Object type=objects[0];
        String login_url = "http://localhost/android/user.php";
        if(type.equals("login")){
            try{

                String username= (String) objects[1];
                String password=(String)objects[2];
                URL url=new URL(login_url);
                HttpURLConnection httpURLConnection=(HttpURLConnection)url.openConnection();
                httpURLConnection.setRequestMethod("POST");
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setDoInput(true);
                OutputStream outputStream=httpURLConnection.getOutputStream();
                BufferedWriter bufferedWriter=new BufferedWriter(new OutputStreamWriter(outputStream,"UTF-8"));
                String post_data= URLEncoder.encode("username","UTF-8")+"="+URLEncoder.encode(username,"UTF-8")+"&"
                        +URLEncoder.encode("username","UTF-8")+"="+URLEncoder.encode(username,"UTF-8");
                bufferedWriter.write(post_data);
                bufferedWriter.flush();
                bufferedWriter.close();
                outputStream.close();
                InputStream inputStream=httpURLConnection.getInputStream();
                BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(inputStream,"iso-8859-1"));
                String result="";
                String line="";
                while(bufferedReader.readLine()!=null){
                    result+=line;
                }
                bufferedReader.close();
                inputStream.close();
                httpURLConnection.disconnect();
                return result;
            }
            catch(MalformedURLException e){
                e.printStackTrace();
            }
            catch (IOException e){
                e.printStackTrace();
            }
        }
        return null;
    }
}