Java 用方法改变 JButton 颜色

Question

我实现了一个带有 25 个 JButton 组件的 JFrame 来表示酒店中的可用房间。我确实知道这不是整个程序，但是我如何创建一种方法，在按下时颜色会发生变化？

可用房间的颜色是绿色，我想将它们更改为红色。

Answer 1

此代码使用 JToggleButton，其中针对标准状态和选定状态具有不同颜色的图标。也可以使用 JCheckBox。

import java.awt.*;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.net.*;
import java.util.*;

public class RoomReservationToggle {

    private JComponent ui = null;
    private String reservedPath = "/image/xj49g.png";
    private String freePath = "/image/zJ8am.png";

    RoomReservationToggle() {
        try {
            initUI();
        } catch (MalformedURLException ex) {
            ex.printStackTrace();
        }
    }

    public void initUI() throws MalformedURLException {
        if (ui != null) {
            return;
        }
        ui = new JPanel(new GridLayout(0, 4, 4, 4));
        ui.setBorder(new EmptyBorder(4, 4, 4, 4));

        ImageIcon reservedIcon = new ImageIcon(new URL(reservedPath));
        ImageIcon freeIcon = new ImageIcon(new URL(freePath));

        Random r = new Random();
        for (int ii = 1; ii < 17; ii++) {
            // a JCheckBox might also be used
            JToggleButton tb = new JToggleButton(freeIcon, r.nextBoolean());
            tb.setSelectedIcon(reservedIcon);
            ui.add(tb);
        }
    }

    public JComponent getUI() {
        return ui;
    }

    public static void main(String[] args) {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (Exception useDefault) {
                }
                RoomReservationToggle o = new RoomReservationToggle();

                JFrame f = new JFrame(o.getClass().getSimpleName());
                f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                f.setLocationByPlatform(true);

                f.setContentPane(o.getUI());
                f.pack();
                f.setMinimumSize(f.getSize());

                f.setVisible(true);
            }
        };
        SwingUtilities.invokeLater(r);
    }
}