iteevent.java

GUI事件处理例子

package example11_11;

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

public class IteEvent extends Frame implements ItemListener {

	static IteEvent frm = new IteEvent();
	static Checkbox chb1, chb2;
	static TextField txt1;

	public static void main(String args[]) {
		frm.setTitle("ItemEvent");
		frm.setSize(240, 160);
		frm.setLayout(new FlowLayout());
		CheckboxGroup grp = new CheckboxGroup();
		chb1 = new Checkbox("green");
		chb2 = new Checkbox("yellow");
		txt1 = new TextField(" None is selected ");
		chb1.setCheckboxGroup(grp);
		chb2.setCheckboxGroup(grp);
		chb1.addItemListener(frm);
		chb2.addItemListener(frm);
		frm.add(chb1);
		frm.add(chb2);
		frm.add(txt1);
		frm.setVisible(true);
	}

	public void itemStateChanged(ItemEvent e) {
		if (e.getSource() == chb1)
			txt1.setText("green is selected");
		else if (e.getSource() == chb2)
			txt1.setText("yellow is selected");
	}
}