Executing PHP scripts using a button from Android app

Issue

I am trying to make a simple app with two buttons each of which would execute a PHP script on my DB, on localhost. So far i have the php script working as intended (tested in browser):

<?php
require 'Connect.php'; // connects to DB

$query = "UPDATE tracker_database
SET tracker_logged_in = '1'
WHERE tracker_username = 'tracker01'";

if(mysqli_query($conn, $query))
{
    echo'Success';
} else {
    echo'not executed';
}
?>

here I have the app's OnClickListener

public void addListenerOnExeBtn() {
    btn_exe = (Button) findViewById(R.id.btn_exe);
    btn_exe.setOnClickListener(
            new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    String link = "http://10.0.3.2/path/to/my/script.php"; //using this IP for Genymotion emulator
                    new updateData().execute(link);
                    Toast.makeText(MainActivity.this, "Executed", Toast.LENGTH_LONG).show();
                }
            }
    );
}

And as far as I understand you need to use AsyncTask to access the scripts

private class updateData extends AsyncTask <String, Void, Void> {

    @Override
    protected Void doInBackground(String... params) {
        try {
            URL url = new URL(params[0]);
            HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
            urlConn.connect();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
}

So my problem is that when I run my app and click the btn_exe it prints out the Toast "Executed" but when I refresh my DB there are no changes, and yes I put the

<uses-permission android:name="android.permission.INTERNET"/>

in my AndroidManifest.xml. I can't find anything wrong in the logcat, no errors, nothing. Anyone has any ideas?

Solution

Ok, so I managed to fix the problem and it was in the updateData method, here is the fixed version if anyone has the same problem:

public class updateData extends AsyncTask<String, String, String> {

    @Override
    protected String doInBackground(String... params) {
        HttpURLConnection conn = null;

        try {
            URL url;
            url = new URL(params[0]);
            conn = (HttpURLConnection) url.openConnection();
            if( conn.getResponseCode() == HttpURLConnection.HTTP_OK ){
                InputStream is = conn.getInputStream();
            }else{
                InputStream err = conn.getErrorStream();
            }
            return "Done";
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if(conn != null) {
                conn.disconnect();
            }
        }
        return null;
    }

Answered By - Matic Tuma