testcheckbox.java~28~

来自「提供了常用的JAVA技术的示例」· JAVA~28~ 代码 · 共 44 行

package CheckBox;

import java.awt.*;
import java.awt.event.*;

public class TestCheckBox {
    private Frame f=new Frame("复选框");

    public TestCheckBox(){
        f.setLayout(new GridLayout(4,1));
        f.setSize(200,200);
        f.addWindowListener(new WindowAdapter(){
          public void windowClosing(WindowEvent e){System.exit(0);}
          });

        CheckboxGroup cbg=new CheckboxGroup();
        Checkbox c1=new Checkbox("one",false,cbg);
        Checkbox c2=new Checkbox("two",false,cbg);
        Checkbox c3=new Checkbox("three",false,cbg);
        Checkbox c4=new Checkbox("four",false,cbg);
        f.add(c1);
        f.add(c2);
        f.add(c3);
        f.add(c4);
        c1.addItemListener(new Handler());
        c2.addItemListener(new Handler());
        c3.addItemListener(new Handler());
        c4.addItemListener(new Handler());

        f.setVisible(true);
    }
    class Handler implements ItemListener{
        String s;
        public void itemStateChanged(ItemEvent e){
            if (e.getStateChange()==ItemEvent.SELECTED)
                {s="selected";}
            if (e.getItem()=="one") s="selected";
            System.out.println(e.getItem()+"  "+s);
        }
    }
    public static void main(String[] args) {
      TestCheckBox testCheckBox1 = new TestCheckBox();
    }
}