Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
import javax.swing.border.LineBorder;
import javax.swing.border.TitledBorder;

public class Main {

    private static final int NB1 = 5;
    private static final int NB2 = 13;
    private static final int NB3 = 15;

    public static void main(String[] args) {

        JFrame f = new JFrame();
        f.setTitle("Example2");
        f.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);

        JPanel p1 = new JPanel(new FlowLayout(FlowLayout.CENTER));
        p1.setBorder(new TitledBorder(new LineBorder(Color.BLACK), "JPanel 1"));
        for (int i = 0; i < NB1; i++)
            p1.add(new JButton("Button " + i));

        JPanel p2 = new JPanel(new FlowLayout(FlowLayout.CENTER));

        p2.setBorder(new TitledBorder(new LineBorder(Color.BLACK), "JPanel 2"));
        for (int i = NB1; i < NB2; i++)
            p2.add(new JButton("Button " + i));

        JPanel p3 = new JPanel(new FlowLayout(FlowLayout.CENTER));
        p3.setBorder(new TitledBorder(new LineBorder(Color.BLACK), "JPanel 3"));
        for (int i = NB2; i < NB3; i++)
            p3.add(new JButton("Button " + i));

        JPanel global = new JPanel(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.fill = GridBagConstraints.HORIZONTAL; // added
        gbc.weightx = 1.0f; // added
        gbc.gridy = 0;
        global.add(p1, gbc);
        gbc.gridy++;
        global.add(p2, gbc);
        gbc.gridy++;
        global.add(p3, gbc);

        f.add(global);
        f.pack();
        f.setVisible(true);

    }

}