Remove title bar with maximum size

Question

package com.company;

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

public class Main extends JFrame{

    private JButton button1;
    private JPanel mainPanel;
    private JCheckBox checkBox1;
    private JCheckBox checkBox2;

    public void command(int x) {
        System.out.println(x);
    }

    public Main() {
//        setSize(300,250);
        setExtendedState(JFrame.MAXIMIZED_BOTH);
        setUndecorated ( true );

        setVisible(true);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setTitle("Menu");
        add(mainPanel);
        button1.addActionListener(ActionEvent -> dispose());
        checkBox1.addActionListener(ActionEvent -> command(2));
        checkBox2.addActionListener(ActionEvent -> command(1));
    }

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

I have a form alongside this as well for the actual buttons. But how would I get it so the window can be maximized but still get rid of the title bar because with these two lines.

        setExtendedState(JFrame.MAXIMIZED_BOTH);
        setUndecorated ( true );

It maximizes it, but it goes over the bottom task bar which isn't how I want it. Is there any way to fix this or another way to just get rid of title bar that'll also let me maximize it.

Answer 1

But how would I get it so the window can be maximized but still get rid of the title bar

You can manually set the size to exclude the task bar:

//setExtendedState(JFrame.MAXIMIZED_BOTH);
setUndecorated ( true );
GraphicsEnvironment env = GraphicsEnvironment.getLocalGraphicsEnvironment();
setBounds(env.getMaximumWindowBounds());
setVisible(true);

This should also work if the task bar is positioned other than the bottom.

Also note that components should be added to the frame BEFORE the frame is made visible.