求助：关于JComboBox

Question

下面一段关于可下拉组合框中显示图片的程序，
不知道哪里有问题，显示不出来，请大虾给点建议啊
JComboBox headpic = new JComboBox();
private String[] pics = new String[] {//头像
                "1.jpg", "3.jpg",
                "5.jpg", "7.jpg"};
ComboBoxModel model = new HeadPicCombobox(pics);
ListCellRenderer renderer = new HeadpicCellRenderer();
class HeadPicCombobox extends DefaultComboBoxModel {//头象列表类
        public HeadPicCombobox(String[] pics) {
                for(int i=0; i < pics.length; ++i) {                        addElement(new Object[] { new ImageIcon(pics[i]) } );
                }
        }        public Icon getIcon(Object object) {
                Object[] array = (Object[])object;
                return (Icon)array[0];
        }
}
class HeadpicCellRenderer extends JLabel implements ListCellRenderer {
        private Border
                lineBorder = BorderFactory.createLineBorder(Color.red, 2),
                emptyBorder = BorderFactory.createEmptyBorder(2,2,2,2);        public HeadpicCellRenderer() {
                setOpaque(true);
        }
        public Component getListCellRendererComponent(JList list,Object value,int index,boolean isSelected,boolean cellHasFocus) {
                HeadPicCombobox model =(HeadPicCombobox)list.getModel();                setIcon(model.getIcon(value));                if(isSelected) {
                        setForeground(list.getSelectionForeground());
                        setBackground(list.getSelectionBackground());
                }
                else {
                        setForeground(list.getForeground());
                        setBackground(list.getBackground());
                }                if(cellHasFocus) setBorder(lineBorder);
                else   setBorder(emptyBorder);                return this;
        }
}

Answer 1

这儿有个Demo，你看看。import java.awt.*;
import java.awt.event.*;
import javax.swing.*;public class JComboBox6{
  String[] s={"西瓜","苹果","草莓","香蕉","葡萄"};
  ImageIcon[] icons=new ImageIcon[5];
  public JComboBox6(){
    JFrame f=new JFrame("JComboBox");
    Container contentPane=f.getContentPane();
        for(int i=0; i < 5; i++)
        {
            icons[i] = new ImageIcon("D:\\OA\\test\\icon\\fruit"+(i+1)+".gif");
        }
        ComboBoxModel mode=new AModel();
        JComboBox combo=new JComboBox(mode);
        combo.setBorder(BorderFactory.createTitledBorder("您喜欢吃哪些水果？"));
        combo.setRenderer(new ACellRenderer());
        combo.setMaximumRowCount(3);
        
        contentPane.add(combo);
        f.pack();
        f.show();
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                    System.exit(0);
            }
        });
  }
  public static void main(String[] args){
   new JComboBox6();
  }
/*我们用JComboBox(ComboBoxModel aModel)来构造图标的JComboBox,因此我们在程序中编写一个继承DefaultComboBoxModel的
ComboBoxModel.
 */
  class AModel extends DefaultComboBoxModel{
    AModel(){
      for (int i=0;i<s.length;i++){
         ItemObj obj=new ItemObj(s[i],icons[i]);
         addElement(obj);
      }
    }
  }
}
class ItemObj
{
    String name;
    ImageIcon icon;
    
    public ItemObj(String name, ImageIcon icon){
        this.name = name;
        this.icon = icon;
    }
}
    
class ACellRenderer extends JLabel implements ListCellRenderer
{
    ACellRenderer()
    {
        setOpaque(true);
    }
    
    public Component getListCellRendererComponent(JList list,
                                                  Object value,
                                                  int index,
                                                  boolean isSelected,
                                                  boolean cellHasFocus)
    {
        if (value != null)
        {
            setText(((ItemObj)value).name);
            setIcon(((ItemObj)value).icon);
        }        if (isSelected) {
            setBackground(list.getSelectionBackground());
            setForeground(list.getSelectionForeground());
        }
        else {
            setBackground(list.getBackground());
            setForeground(list.getForeground());
        }        return this;
    }    
}

Answer 2

谢谢大家，问题已解决，出在jpg格式不能显示。再次感谢！