Question

I’m creating GUI and I don’t know how to resolve my problem. What I’d like to do is to create several panels from PanelClass like i did in Main.

I don’t know how:

1. Name buttons in my Panels and gave them some functionality (Like i was trying with button b1)
2. Add to panel3 additional labels, and buttons.

My main class

public class Main {

    JFrame f;
    PanelClass panel1, panel2, panel3;
    JButton b1, b2;

    public Main() {

        b1 = new JButton("asasa");

        f = new JFrame();
        f.setSize(300, 300);
        f.setLayout(new GridBagLayout());
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        panel1 = new PanelClass(b1, b2, panel1);
        panel2 = new PanelClass(b1, b2, panel2);
        panel3 = new PanelClass(b1, b2, panel3);

        f.add(panel1);
        f.add(panel2);
        f.add(panel3);
    }

    public static void main(String[] args) {    
        Main m = new Main();    
    }    
}

My Panel class

public class PanelClass extends JPanel {

    public PanelClass(JButton btn, JButton btn1, JPanel p) {

        super();
        p = new JPanel(new GridBagLayout());
        btn = new JButton();
        btn1 = new JButton();

        GridBagConstraints c = new GridBagConstraints();

        c.gridx = 0;
        c.gridy = 0;
        p.add(btn, c);
        c.gridx = 0;
        c.gridy = 1;
        p.add(btn1, c);
        add(p);
    }
}

Answer 1

1. A component can only exist in one visible container at a time (unless it is being used as a flyweight renderer). So putting the same buttons into 3 panels will not work.
2. The code passes a button(s) in the constructor of PanelClass which is(are) ignored. Instead 2 new button instances are created. Just assign the passed buttons to the ..I was going to say ‘class level attributes’ when I noted they were not. Entirely remove
   btn = new JButton(); and the text passed in the button constructor will appear.
3. For events, see How to Write an Action Listener.