Question

I am new to Java (knowing OOPS concepts as I am ASP.NET member but not doing Java from last 2 years), creating Tic-Tac-Toe game.

Deleted code here as I am putting my code below.

Here, I am wondering how below lines are working?

game frame = new game();
frame.setVisible(true);

I understood that frame is Object of game Class and initialized by new game() Constructor but not understanding that how .setVisible() method works for this object.

And one more difficulty I am facing is how can I access initialized objects in other classes or methods.

---

Hello,
I asked previous question because I am facing this difficulty here :
First I’ll give code

public class Game extends JFrame {


    private JPanel contentPane;
    //private JPanel settingPane;

    protected JLabel lblPlayerName2; // I am using this one for my testing
    JLabel[] lbls = new JLabel[9];
    private final ButtonGroup buttonGroup = new ButtonGroup();


    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Game frame = new Game();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */

    public Game() {
        setTitle("Tic Tac Toe");
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 810, 607);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);
        contentPane.setName("Tic Tac Toe");
.       
.
..
.
.
.
.
.
.
.
.
.

    for (int i=0; i<lbls.length; i++) {
        lbls[i] = new JLabel(""+(i+1));
        lbls[i].addMouseListener(new AllbtnBehvr());

        lbls[i].setFont(new Font("Trebuchet MS", Font.BOLD, 95));
        lbls[i].setHorizontalAlignment(SwingConstants.CENTER);
        lbls[i].setBorder(new LineBorder(new Color(0, 0, 0), 2));
        panelGameArea.add(lbls[i]);
    }
        .
    .
    .
    .
    .
    .

    .
    .
    .
    .
    .
    .

} // End of Game() 

class AllbtnBehvr implements MouseInputListener{ //Created this class as SubClass of Game Class

        @Override
        public void mouseClicked(MouseEvent src) {
            // TODO Auto-generated method stub

            JLabel b = (JLabel) src.getSource();
            lblPlayerName2.setText(b.getText());


.       }
...
.
.
.
.
.
.
} // End of AllbtnBehvr
}// End of Game Class

Here, I observed that, variable ‘lblPlayerName2’ and lbls[] defined outside of Game() Constructor, and it can be accessed, but other variables inside Game() cannot be accessed.
Here, I want to ask,

How can I access to variables inside Game()? and
How can I access to variables inside Game() if I create class outside Game Class?

Answer 1

game extends JFrame, which in turn extends java.awt.Window, so inherits its methods.

PS. Classes should be named with a capital first letter. Game.