Unable to increase cell width in GridBag Layout

Question

I am following this tutorial and setting up my GUI. What I want a single textarea should occupy entire width (all columns) but it is not happening and screen like this:

This Cyan field should capture the width of entire screen. Below is my code:

Code

package com.company.app;

import javax.swing.*;
import java.awt.*;


public class SpamGUI {

    public static void main(String[] args) {
        System.out.println("Loading Program..");
        try {
            UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
        } catch (Exception e) {
            e.printStackTrace();
        }
        JFrame frame = new JFrame("Evil App");
        frame.setSize(800, 500);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        //frame.setResizable(false);


        JPanel panel = new JPanel();

        panel.setLayout(new GridLayout(3, 3));
        //panel.setLayout(new GridLayout());

        GridBagConstraints c = new GridBagConstraints();
        c.fill = GridBagConstraints.HORIZONTAL;

        panel.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);

        /**
         * Training File Section Path
         */
        JLabel lblTrainPath = new JLabel("Enter Training Folder Path");
        lblTrainPath.setSize(100, 10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 0;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(lblTrainPath, c);

        JTextField txtTrainPath = new JTextField();
        txtTrainPath.setSize(100, 20);
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 0;
        c.gridy = 1;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(txtTrainPath, c);

        JButton btnTrainPath = new JButton("Browse..");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 2;
        c.weightx = 0.5;
        c.weighty = 0.5;
        c.gridwidth = 3;
        panel.add(btnTrainPath, c);

        /**
         * Testing File Section Path
         */

        JLabel lblTestingPath = new JLabel("Enter Testing Folder Path");
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 1;
        c.gridy = 0;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(lblTestingPath, c);

        JTextField txtTestPath = new JTextField();
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 1;
        c.gridy = 1;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(txtTestPath, c);

        JButton btnTestPath = new JButton("Browse..");
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 1;
        c.gridy = 2;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(btnTestPath, c);

        /**
         * Pogress Section
         */
        JTextArea txtProgress = new JTextArea();
        txtProgress.setBackground(Color.cyan);
        txtProgress.setOpaque(true);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 2;
        c.gridy = 0;
        c.ipadx = 50;
        c.weightx = 0.5;
        c.weighty = 0.5;
        c.gridwidth = 2;

        panel.add(txtProgress, c);

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

    }
}

Answer 1

• The layout was wrong.
• The gridx/gridy orders were reversed.
• The gridwidth was randomly set to 3 too early.
• Text field width should be set in columns.
• Text area size should be specified in columns and rows.

.. That's all I can remember changing.

import javax.swing.*;
import java.awt.*;

public class SpamGUI {

    public static void main(String[] args) {
        System.out.println("Loading Program..");
        try {
            UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
        } catch (Exception e) {
            e.printStackTrace();
        }
        JFrame frame = new JFrame("Evil App");
        //frame.setSize(800, 500);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        //frame.setResizable(false);


        JPanel panel = new JPanel();

        panel.setLayout(new GridBagLayout());
        //panel.setLayout(new GridLayout());

        GridBagConstraints c = new GridBagConstraints();
        c.fill = GridBagConstraints.HORIZONTAL;

        panel.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);

        /**
         * Training File Section Path
         */
        JLabel lblTrainPath = new JLabel("Enter Training Folder Path");
        //lblTrainPath.setSize(100, 10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 0;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(lblTrainPath, c);

        JTextField txtTrainPath = new JTextField(10);
        //txtTrainPath.setSize(100, 20);
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 1;
        c.gridy = 0;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(txtTrainPath, c);

        JButton btnTrainPath = new JButton("Browse..");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 2;
        c.gridy = 0;
        c.weightx = 0.5;
        c.weighty = 0.5;
        //c.gridwidth = 3;
        panel.add(btnTrainPath, c);

        /**
         * Testing File Section Path
         */

        JLabel lblTestingPath = new JLabel("Enter Testing Folder Path");
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 0;
        c.gridy = 1;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(lblTestingPath, c);

        JTextField txtTestPath = new JTextField(10);
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 1;
        c.gridy = 1;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(txtTestPath, c);

        JButton btnTestPath = new JButton("Browse..");
        c.fill = GridBagConstraints.FIRST_LINE_END;
        c.gridx = 2;
        c.gridy = 1;
        c.weightx = 0.5;
        c.weighty = 0.5;
        panel.add(btnTestPath, c);

        /**
         * Pogress Section
         */
        JTextArea txtProgress = new JTextArea(5,15);
        txtProgress.setBackground(Color.cyan);
        txtProgress.setOpaque(true);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 2;
        c.ipadx = 50;
        c.weightx = 0.5;
        c.weighty = 0.5;
        c.gridwidth = 3;

        panel.add(txtProgress, c);

        frame.add(panel);
        frame.pack();
        frame.setVisible(true);
    }
}

Parting tip:

That GUI is badly in need of some white space. Change that something like changing:

    c.fill = GridBagConstraints.HORIZONTAL;

To:

    c.fill = GridBagConstraints.HORIZONTAL;
    c.insets = new Insets(5,5,5,5);