java 下拉列表框

 1 package test; 2  3 import java.awt.Container; 4 import java.awt.GridLayout; 5 import java.awt.event.WindowAdapter; 6 import java.awt.event.WindowEvent; 7 import java.util.Vector; 8  9 import javax.swing.BorderFactory;10 import javax.swing.JCheckBox;11 import javax.swing.JComboBox;12 import javax.swing.JFrame;13 import javax.swing.JLabel;14 import javax.swing.JPanel;15 import javax.swing.JRadioButton;16 17 class MyRadio{18     private JFrame f=new JFrame("welcome to use!");19     private Container cont=f.getContentPane();20     private JComboBox jcb1=null;21     private JComboBox jcb2=null;22     public MyRadio(){23         this.f.setLayout(new GridLayout(2,2));24         String nations[]={"China","Brazil","America","Korean","Italy","France"25     };26         Vector<String> v=new Vector<String>();27         v.add("hjw");28         v.add("LJD");29         v.add("zk");30         this.jcb1=new JComboBox(nations);31         this.jcb2=new JComboBox(v);32         jcb1.setBorder(BorderFactory.createTitledBorder("Which country do you want to travel?"));33         jcb2.setBorder(BorderFactory.createTitledBorder("Who do you like best?"));34         jcb1.setMaximumRowCount(3);35         jcb2.setMaximumRowCount(3);36         cont.add(this.jcb1);37         cont.add(this.jcb2);38         cont.add(new JLabel("下拉框"));39         this.f.setSize(300,150);40         this.f.setVisible(true);41         this.f.addWindowListener(new WindowAdapter(){42             public void windowClosing(WindowEvent arg0){43                 System.exit(1);44             }45         });46     }47 }48 public class test {49     public static void main(String[] args) {50         new MyRadio();51         52     }53 54 55 }