selectmodebuttondemo.java

JAVA编程思想源代码 值得一下 很难找的

package chapter11;

import javax.swing.*;

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.*;

public class SelectModeButtonDemo extends JApplet implements ItemListener,
		ActionListener {

	int x = 0, y = 0, sum = 0, a = 0, b = 0, c = 0;

	JTextField tf = new JTextField(10);

	JLabel lb = new JLabel("总数:");

	JCheckBox cb;

	JRadioButton rb1, rb2, rb3;

	ButtonGroup bg = new ButtonGroup();

	public void init() {
		setLayout(new FlowLayout());
		cb = new JCheckBox("笔10", false);
		cb.addItemListener(this);
		add(cb);
		cb = new JCheckBox("书80", false);
		cb.addItemListener(this);
		add(cb);
		cb = new JCheckBox("本20", false);
		cb.addItemListener(this);
		add(cb);
		rb1 = new JRadioButton("全班40人");
		rb1.addActionListener(this);
		add(rb1);
		rb2 = new JRadioButton("全班30人");
		rb2.addActionListener(this);
		add(rb2);
		rb3 = new JRadioButton("全班20人");
		rb3.addActionListener(this);
		add(rb3);
		bg.add(rb1);
		bg.add(rb2);
		bg.add(rb3);
		add(lb);
		add(tf);

	}

	public void itemStateChanged(ItemEvent e) {
		JCheckBox cbx = (JCheckBox) e.getItem();
		if (cbx.getText() == "笔10")
			a = 10;
		if (cbx.getText() == "书80")
			b = 80;
		if (cbx.getText() == "本20")
			c = 20;
		x = a + b + c;
		sum = x * y;
		tf.setText(String.valueOf(sum) + "元");
	}

	public void actionPerformed(ActionEvent e) {
		String rbt = e.getActionCommand();
		if (rbt == "全班40人")
			y = 40;
		else if (rbt == "全班30人")
			y = 30;
		else
			y = 20;
		sum = x * y;
		tf.setText(String.valueOf(sum) + "元");
	}

}