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| import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Vector;
import javax.swing.AbstractListModel;
import javax.swing.BorderFactory;
import javax.swing.ComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
class MyComboBoxModel extends AbstractListModel implements ComboBoxModel{
String nations[] = {"中国","美国","韩国","法国","英国"};
String item = null;
@Override
public int getSize() {
// TODO 自动生成的方法存根
return this.nations.length;
}
@Override
public Object getElementAt(int index) {
// TODO 自动生成的方法存根
return this.nations[index];
}
@Override
public void setSelectedItem(Object anItem) {
// TODO 自动生成的方法存根
this.item = (String) anItem;
}
@Override
public Object getSelectedItem() {
// TODO 自动生成的方法存根
return this.item;
}
}
class MyComboBox{
private JFrame frame = new JFrame("窗体"); //定义窗体
private Container cont = frame.getContentPane(); //得到窗体容器
private JComboBox jcb1 = null; //定义下拉列表框
private JComboBox jcb2 = null; //定义下拉列表框
public MyComboBox(){
this.frame.setLayout(new GridLayout(2,2));
// String nations[] = {"中国","美国","韩国","法国","英国"};
// Vector<String> v = new Vector<String>(); //定义一个Vector集合
// v.add("元素1");
// v.add("元素2");
// v.add("元素3");
// this.jcb1 = new JComboBox(nations);
// this.jcb2 = new JComboBox(v);
this.jcb1 = new JComboBox(new MyComboBoxModel()); //实例化JComboBox
//定义一个列表框的边框显示条
jcb1.setBorder(BorderFactory.createTitledBorder("哪个国家？"));
// jcb2.setBorder(BorderFactory.createTitledBorder("Vector?"));
jcb1.setMaximumRowCount(3); //最多显示3个选项
// jcb2.setMaximumRowCount(3);
cont.add(this.jcb1);
// cont.add(this.jcb2);
cont.add(new JLabel("下拉列表框"));
this.frame.setSize(330,200);
this.frame.setVisible(true);
this.frame.addWindowListener(new WindowAdapter(){ //加入事件监听
public void windowClosing(WindowEvent arg0) { //窗口关闭时触发，按下关闭按钮
// TODO 自动生成的方法存根
System.out.println("windowClosing-->窗口关闭");
System.exit(1);
}
});
}
}
public class MyComboBox_demo {
public static void main(String[] args) {
// TODO 自动生成的方法存根
new MyComboBox();
}
}
|
