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/*
 * @Author: your name
 * @Date: 2020-11-04 10:19:14
 * @LastEditTime: 2020-11-04 10:28:50
 * @LastEditors: Please set LastEditors
 * @Description: In User Settings Edit
 * @FilePath: /java/calcu/RadioButtonFrame.java
 */

package calcu;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class RadioButtonFrame extends JFrame {
    private JPanel buttonPanel;
    private ButtonGroup group;
    private JLabel label;
    private static final int DEFAULT_SIZE = 36;

    public static void main(String[] args) {
        RadioButtonFrame t = new RadioButtonFrame();
        t.setTitle("ImageTest");
        t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        t.setVisible(true);
    }

    public RadioButtonFrame() {
        label = new JLabel("The quick brown fox jumps over the lazy dog.");
        label.setFont(new Font("Serif", Font.PLAIN, DEFAULT_SIZE));
        add(label, BorderLayout.CENTER);

        // add the radio buttons
        buttonPanel = new JPanel();
        group = new ButtonGroup();

        addRadioButton("Small", 8);
        addRadioButton("Medium", 12);
        addRadioButton("Large", 18);
        addRadioButton("Extra large", 36);

        add(buttonPanel, BorderLayout.SOUTH);
        pack();
    }

    public void addRadioButton(String name, int size) {
        boolean selected = size == DEFAULT_SIZE;
        JRadioButton button = new JRadioButton(name, selected);
        group.add(button);
        buttonPanel.add(button);

        // this listener sets the label font size
        ActionListener listener = event -> label.setFont(new Font("Serif", Font.PLAIN, size));

        button.addActionListener(listener);
    }
}