Positioning of JButtons in a JPanel with BoxLayout over JLabel in JPanel with Overlaylayout

Question

I'm making a menu for my game. I want the background to be animated. Therefore I use a JLabel with a gif. On top of this I want my buttons. But, I want some air between the buttons and the left side of the window. That gives me trouble.

This is my result. It's pretty good! But I can't get the gray bar to disappear! Also, it looks like my background JLabel is being pushed a tad to the right.

I have three classes:

1 The launcher that creates the JFrame

public class Launcher extends JFrame{

    public int speed = 0;

    int c = 0;
    public final static int WIDTH = 1200;
    public final static int HEIGHT = 800;
    Game game;
    JFrame frame;


    public static void main(String[] args) throws IOException{

        new Launcher();


    }

    public Launcher() throws IOException{

        game = new Game();
        JFrame frame = new JFrame("PingPong!");
        frame.add(game);
        frame.setFocusable(true);
        frame.setPreferredSize(new Dimension(WIDTH, HEIGHT) );
        frame.setVisible(true);
        frame.setResizable(false);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);



    }




}

2 The Game that creates a JPanel with OverlayLayout

public class Game extends JPanel implements Runnable{

    public State menuState;


    public Game() throws IOException{
        this.removeAll();
        this.setLayout(new OverlayLayout(this));

        menuState = new MenuState(this, handler);
    }
}

3 And finally my MenuState that creates a JPanel with BoxoLayout where I add the elements

public class MenuState extends State{

    JPanel menuPanel;

    JLabel background;

    private Icon backgroundIcon;

    private Icon newgameIcon;
    private Icon loadgameIcon;

    private JButton newGame;
    private JButton loadGame;

    Border border;

    public MenuState(Game game, Handler handler) {
        super(game, handler);       

        init();


    }       

    public void init(){

        menuPanel = new JPanel();
        menuPanel.setLayout(new BoxLayout(menuPanel, BoxLayout.PAGE_AXIS));
        menuPanel.setBackground(Color.green);
        menuPanel.add(Box.createHorizontalStrut(100));
        menuPanel.setVisible(true);
        menuPanel.setOpaque(false);



        Box left = Box.createVerticalBox();

        backgroundIcon = new ImageIcon("res/images/menu/back.gif");
        background = new JLabel(backgroundIcon);

        newGame = new JButton("New Game");  
        loadGame = new JButton("Load Game");

        game.add(menuPanel);

        menuPanel.add(newGame);


        left.add(newGame);
        left.add(Box.createRigidArea(new Dimension(0, 40)));
        left.add(loadGame);
        left.add(Box.createRigidArea(new Dimension(0, 300)));
        left.setOpaque(false);


        menuPanel.add(left);

        background.setSize(1200, 800);
        game.add(background);   


    }


}

I have tried different order of adding the components. I have tried Opacity true and false.

I wish I could just set newGame.setLocation(100, 500) and the box would be placed where I wanted it.

Answer 1

But, I want some air between the buttons and the left side of the window.

1. Add your buttons to a JPanel and make the JPanel non-opaque.
2. Then you can add an EmptyBorder to the panel to give the buttons spacing within the panel.
3. Then you add the panel to the overlay layout using the appropriate alignmentx/y values.

You can play with the alignment values using the demo code found here: Java Layout with Component always in Top Right

If I understand your requirement you should be using setAlignmentX(0.0) and setAlignmentY(0.5);

So to simply your code it should be something like:

JLabel background = new JLabel(...);
background.setAlignmentX(0.0f);
background.setAlignmentY(0.5f);

JPanel buttonsPanel = new JPanel( set your layout );
buttonsPanel.setOpaque( false );
buttonsPanel.setBorder( new EmptyBorder(...) );
buttonsPanel.setAlignmentX(0.0f);
buttonsPanel.setAlignmentY(0.5f);

JPanel overlayPanel = new JPanel( new OverLayLayout(...) );
overlayPanel.add(background);
overlayPanel.add(buttonsPanel);