实现JComBox item项tip信息

public class Test3 {

 public static void main(String[] args) {  new Test3().init(); }  private void init(){  Object[] objs={"aaaaaa","bbbbbbbb","cccccccc","ddddddd"};  JComboBox cbo=new JComboBox(objs);  cbo.setToolTipText(cbo.getSelectedItem()!=null?cbo.getSelectedItem().toString():"");  cbo.setRenderer(new ItemTipRenderer());//继承BasicComboBoxRenderer类

  JFrame f=new JFrame();  f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  f.setSize(50, 100);  f.setLocation(400, 200);  f.add(cbo,BorderLayout.SOUTH);  f.setVisible(true);   } }

 

 

@SuppressWarnings("serial")//实现JComBox item项tip信息 class ItemTipRenderer extends BasicComboBoxRenderer {  public Component getListCellRendererComponent(JList list, Object value,    int index, boolean isSelected, boolean cellHasFocus) {   if (isSelected){    setBackground(list.getSelectionBackground());    setForeground(list.getSelectionForeground());   }else{    setBackground(list.getBackground());    setForeground(list.getForeground());   }      if (-1 < index){    list.setToolTipText(value.toString());   }       setFont(list.getFont());   setText((value == null) ? "" : value.toString());   return this;  } }