Question

How do I make the subpanels within my main panel stay where they are when I set one of the subpanels to be invisible?

What I have looks like:

[ (Panel1) (Panel2) (Panel3) (Panel4) ]

When I do panel3.setVisible(false) it then looks like:

[      (Panel1) (Panel2) (Panel4)     ]

I would like it to look like:

[ (Panel1) (Panel2)          (Panel4) ]

I am using the GridBagLayout and my mainPanel declaration looks like:

final JPanel panel = new JPanel(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();

and I add an new panel like:

final JTextField valueTextField = new JTextField();
valueTextField.setPreferredSize(new Dimension(80, 25));
valueTextField.setName("Value");
c.gridx =0;
panel.add(valueTextField, c);

I’ll provide more code if needed and I don’t care which layout I use as long as it gets me what I want.

Answer 1

I suggest using a CardLayout within the individual cells, and instead of setting it to invisible, switch to an empty panel instead.

The code below demonstrates this. Within hidePanel() there are two options to hide the cell with the CardLayout route currently enabled.

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class InvisiblePanels {
    public static void main(String... args) throws Exception {
        JFrame frame = new JFrame();
        frame.setLayout(new GridBagLayout());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        GridBagConstraints c = new GridBagConstraints();
        c.gridx = 0;
        frame.add(new MyPanel(), c);
        c.gridx = 1;
        frame.add(new MyPanel(), c);
        c.gridx = 2;
        frame.add(new MyPanel(), c);

        frame.pack();
        frame.setVisible(true);

    }

    private static class MyPanel extends JPanel {

        CardLayout layout;

        public MyPanel() {
            layout = new CardLayout();
            setLayout(layout);
            JButton button = new JButton("Click me");
            button.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    hidePanel();
                }
            });
            add(button, "visible");
            add(new JPanel(), "invisible");
            layout.show(this, "visible");
        }

        public void hidePanel() {
//            setVisible(false);
            layout.show(this, "invisible");
        }
    }
}