JComboBox 下拉选项显示图标

妖狐艹你老母 2024-04-07 14:43 78阅读 0赞

#### JComboBox 下拉选项显示图标 ####

*  1.需求描述
 *  2.代码实现
 *  3.效果演示

> 系统：Win10  
> JDK：1.8.0\_333  
> IDEA：2020.3.4

## 1.需求描述 ##

最近在做一个 Swing 项目的时候，使用到了 JComboBox 组件，在显示下拉选项的时候，我想要在原数据的基础上，显示图标

## 2.代码实现 ##

说明：如果需要测试的话，需要修改获取自己本地图标的代码

import javax.swing.*;
    import java.awt.*;
    import java.awt.event.ActionEvent;
    import java.awt.event.ActionListener;
    import java.util.HashMap;
    import java.util.Map;
    
    /**
     * @ClassName JComboBoxDemo
     * @Description JComboBox 显示图标
     * @Author Li
     * @Date 2022/8/28 20:35
     * @ModifyDate 2022/8/28 20:35
     * @Version 1.0
     */
    public class JComboBoxDemo extends JFrame {
        
        public static String PATH = JComboBoxDemo.class.getResource("/").getPath();
    
        private JComboBox comboBox;
    
        public JComboBoxDemo() {
        
            this.setTitle("JComboBox 显示图标");
            this.setLayout(new BorderLayout());
            ImageIcon SUNNY = new ImageIcon(PATH + "images/sunny.png");
            ImageIcon CLOUDY = new ImageIcon(PATH + "images/cloudy.png");
            ImageIcon RAIN = new ImageIcon(PATH + "images/rain.png");
            ImageIcon SNOW = new ImageIcon(PATH + "images/snow.png");
            Map<Object, Icon> map = new HashMap<>();
            map.put("晴天", SUNNY);
            map.put("刮风", CLOUDY);
            map.put("下雨", RAIN);
            map.put("下雪", SNOW);
    
            JPanel contentPane = new JPanel();
            comboBox = new JComboBox();
            comboBox.setRenderer(new IconListCellRenderer(map));
            comboBox.addItem("晴天");
            comboBox.addItem("刮风");
            comboBox.addItem("下雨");
            comboBox.addItem("下雪");
    
            // 监听下拉选
            comboBox.addActionListener(new ActionListener() {
        
                @Override
                public void actionPerformed(ActionEvent e) {
        
                    System.out.println(comboBox.getSelectedItem());
                }
            });
    
            contentPane.add(comboBox, BorderLayout.NORTH);
            this.setContentPane(contentPane);
    
            this.setSize(new Dimension(400, 300));
            this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            this.setLocationRelativeTo(null);
            this.setVisible(true);
        }
    
        public static void main(String[] args) {
        
            new JComboBoxDemo();
    
        }
    
        class IconListCellRenderer extends DefaultListCellRenderer {
        
            private Map<Object, Icon> icons;
    
            public IconListCellRenderer(Map<Object, Icon> icons) {
        
                this.icons = icons;
            }
    
            @Override
            public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        
                JLabel label = (JLabel) super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
                // 从图标集合里获取对应图标
                Icon icon = icons.get(value);
                if (icon == null) {
        
                    icon = icons.get("晴天");
                }
                label.setIcon(icon);
                return label;
            }
        }
    }

## 3.效果演示 ##

![在这里插入图片描述][c310c18754544960a7af0993ef10d190.gif]

[c310c18754544960a7af0993ef10d190.gif]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/00e5ecbb48644eb89d63f91deaf5930c.gif