StartScreen.java

package com.mygdx.game;

import com.badlogic.gdx.Game;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Screen;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Pixmap;
import com.badlogic.gdx.graphics.Pixmap.Format;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.BitmapFont;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.scenes.scene2d.Actor;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.ui.Skin;
import com.badlogic.gdx.scenes.scene2d.ui.TextButton;
import com.badlogic.gdx.scenes.scene2d.ui.TextButton.TextButtonStyle;
import com.badlogic.gdx.scenes.scene2d.utils.ChangeListener;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.InetAddress;
import java.net.URL;

public class StartScreen implements Screen {
    Skin skin;
    Stage stage;
    SpriteBatch batch;
    Game g;

    Texture background;
    public StartScreen(Game g){
        create();
        this.g=g;
    }

    public void create(){
        try {
            registerRoom();
        } catch (Exception e){
            e.printStackTrace();
        }
        batch = new SpriteBatch();
        background = new Texture("bg_album_art.jpg");
        stage = new Stage();
        Gdx.input.setInputProcessor(stage);

        // A skin can be loaded via JSON or defined programmatically, either is fine. Using a skin is optional but strongly
        // recommended solely for the convenience of getting a texture, region, etc as a drawable, tinted drawable, etc.
        skin = new Skin();
        // Generate a 1x1 white texture and store it in the skin named "white".
        Pixmap pixmap = new Pixmap(100, 100, Format.RGBA8888);
        pixmap.setColor(Color.BLUE);
        pixmap.fill();

        skin.add("white", new Texture(pixmap));

        // Store the default libgdx font under the name "default".
        BitmapFont bfont=new BitmapFont();
        bfont.getData().setScale(1);
        skin.add("default",bfont);

        // Configure a TextButtonStyle and name it "default". Skin resources are stored by type, so this doesn't overwrite the font.
        TextButtonStyle textButtonStyle = new TextButtonStyle();
        textButtonStyle.up = skin.newDrawable("white", Color.DARK_GRAY);
        textButtonStyle.down = skin.newDrawable("white", Color.DARK_GRAY);
        textButtonStyle.checked = skin.newDrawable("white", Color.BLUE);
        textButtonStyle.over = skin.newDrawable("white", Color.LIGHT_GRAY);

        textButtonStyle.font = skin.getFont("default");

        skin.add("default", textButtonStyle);

        // Create a button with the "default" TextButtonStyle. A 3rd parameter can be used to specify a name other than "default".
        final TextButton textButton=new TextButton("PLAY",textButtonStyle);
        textButton.setSize(200, 80);
        textButton.setPosition(583, 344);
        stage.addActor(textButton);
        stage.addActor(textButton);
        stage.addActor(textButton);

        // Add a listener to the button. ChangeListener is fired when the button's checked state changes, eg when clicked,
        // Button#setChecked() is called, via a key press, etc. If the event.cancel() is called, the checked state will be reverted.
        // ClickListener could have been used, but would only fire when clicked. Also, canceling a ClickListener event won't
        // revert the checked state.
        textButton.addListener(new ChangeListener() {
            public void changed (ChangeEvent event, Actor actor) {
                System.out.println("Clicked! Is checked: " + textButton.isChecked());
                textButton.setText("Starting new game");
                g.setScreen( new RoomScreen(g));
            }
        });
    }

    public void render (float delta) {
        Gdx.gl.glClearColor(0.2f, 0.2f, 0.2f, 1);
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
        batch.begin();
        batch.draw(background, 0, 0);
        batch.end();
        stage.act(Math.min(Gdx.graphics.getDeltaTime(), 1 / 30f));
        stage.draw();
        stage.setDebugAll(true);
    }

    @Override
    public void resize (int width, int height) {
        //stage.setViewport(width, height, false);
    }

    @Override
    public void dispose () {
        stage.dispose();
        skin.dispose();
    }

    @Override
    public void show() {
        // TODO Auto-generated method stub

    }

    @Override
    public void hide() {
        // TODO Auto-generated method stub

    }

    @Override
    public void pause() {
        // TODO Auto-generated method stub

    }

    @Override
    public void resume() {
        // TODO Auto-generated method stub
    }

    private void registerRoom() throws Exception {
        String url = "http://spacecharge.co.nf/php/room_add.php";
        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();

        //add reuqest header
        con.setRequestMethod("POST");
        //con.setRequestProperty("User-Agent", USER_AGENT);
        con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");

        InetAddress IP = InetAddress.getLocalHost();

        //System.out.print(IP.getHostAddress());
        String urlParameters = "ipAdd=" + IP.getHostAddress();

        // Send post request
        con.setDoOutput(true);
        DataOutputStream wr = new DataOutputStream(con.getOutputStream());
        wr.writeBytes(urlParameters);
        wr.flush();
        wr.close();

        int responseCode = con.getResponseCode();
        System.out.println("\nSending 'POST' request to URL : " + url);
        System.out.println("Post parameters : " + urlParameters);
        System.out.println("Response Code : " + responseCode);

        BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuilder response = new StringBuilder();

        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();
        //print result
        System.out.println("Room Code: " + response.toString());
        MyGdxGame.RoomID = response.toString();
    }
}