Java Swing - JComboBox with Icons Example

Following example shows JCombo with a custom renderer having items with icons.

public class JComboBoxExample {
    public static void main(String[] args) {
        List<Employee> employees = EmployeeDataAccess.getEmployees();
        JComboBox<Employee> comboBox = new JComboBox<>(employees.toArray(new Employee[employees.size()]));
        //renderer
        comboBox.setRenderer(new ExampleRenderer());
        //wrap in a panel
        JPanel panel = new JPanel();
        panel.add(comboBox);
        //frame
        JFrame frame = createFrame();
        frame.add(panel);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private static JFrame createFrame() {
        JFrame frame = new JFrame("JComboBox Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(new Dimension(600, 300));
        return frame;
    }
}

public class ExampleRenderer extends DefaultListCellRenderer {
    private Map<String, ImageIcon> iconMap = new HashMap<>();
    private Color background = new Color(0, 100, 255, 15);
    private Color defaultBackground = (Color) UIManager.get("List.background");

    public ExampleRenderer() {
        iconMap.put("Account", new ImageIcon(getClass().getResource("/images/account.png")));
        iconMap.put("Sales", new ImageIcon(getClass().getResource("/images/sales.png")));
        iconMap.put("IT", new ImageIcon(getClass().getResource("/images/it.png")));
        iconMap.put("Admin", new ImageIcon(getClass().getResource("/images/admin.png")));
    }

    @Override
    public Component getListCellRendererComponent(JList<?> list, Object value, int index,
                                                  boolean isSelected, boolean cellHasFocus) {
        super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
        Employee emp = (Employee) value;
        this.setText(emp.getName());
        this.setIcon(iconMap.get(emp.getDept()));
        if (!isSelected) {
            this.setBackground(index % 2 == 0 ? background : defaultBackground);
        }
        return this;
    }
}

The four icons loaded in above code is already in the folder src/main/resources/images/.

public class EmployeeDataAccess {

    public static List<Employee> getEmployees() {
        List<Employee> list = new ArrayList<>();
        String[] depts = {"IT", "Account", "Admin", "Sales"};
        DataFactory df = new DataFactory();
        for (int i = 1; i <= 30; i++) {
            Employee e = new Employee();
            e.setName(df.getName());
            e.setAddress(df.getAddress() + ", " + df.getCity());
            e.setDept(df.getItem(depts));
            e.setPhone(df.getNumberText(3) + "-" + df.getNumberText(3) +
                    "-" + df.getNumberText(4));
            list.add(e);
        }
        return list;
    }
}

public class Employee {
    private String name;
    private String dept;
    private String phone;
    private String address;
    .............
}

Output

Example Project

Dependencies and Technologies Used:

• datafactory 0.8: Library to generate data for testing.
• JDK 1.8
• Maven 3.3.9