import java.awt.*;import java.awt.event.*;import javax.swing.*;import java.applet.*;public class lzjjsq implements ActionListener {Panel p1,p2,p3;Label l1,l2,l3,l4;Button b1,b2,b3,b4,b5,b6;TextField t1,t2,t3;public lzjjsq() {//窗体布局t1=new TextField(15);t2=new TextField(15);t3=new TextField(15);b1=new Button("加+");b2=new Button("减-");b3=new Button("乘*");b4=new Button("除/");b5=new Button("清除");b6=new Button("退出");l1=new Label("我的计算器",Label.CENTER);l2=new Label(" 请输入第一个数： 请输入第二个数：",Label.CENTER);l3=new Label("结果：",Label.CENTER);l4=new Label("设计者：我 学号：2012070",Label.CENTER); FlowLayout panelLayout = new FlowLayout(FlowLayout.CENTER);//所有面板的样式居中Font myFont = new Font("宋体",Font.BOLD,20);//设置主窗口字体 Font tFont = new Font("华文彩云",Font.BOLD,20);//设置主窗口字体p1= new Panel(); p1.setLayout(panelLayout); p1.add(t1);p1.add(t2); p2=new Panel();p2.setLayout(panelLayout); p2.add(b1);p2.add(b2);p2.add(b3);p2.add(b4);p2.add(b5);p2.add(b6);p3=new Panel(); p3.setLayout(panelLayout); p3.add(t3); Frame f1=new Frame("我~的计算器"); f1.setSize(450,450); f1.setLocation(450,450); f1.setBackground(Color.yellow); l1.setFont(tFont); f1.setFont(myFont);f1.setLayout(new GridLayout(7,1)); f1.setVisible(true); //Frame可见性为真，才可显示 f1.add(l1);f1.add(l2);f1.add(p1);f1.add(p2); f1.add(l3);f1.add(p3);f1.add(l4); //调用按钮事件b1.addActionListener(this);b2.addActionListener(this);b3.addActionListener(this);b4.addActionListener(this);b5.addActionListener(this);b6.addActionListener(this); }//定义按钮事件public void actionPerformed(ActionEvent e) {Button b=(Button)e.getSource(); String m = t1.getText();String n = t2.getText();if(b==b1){try{t3.setText(String.valueOf(Float.parseFloat(m)+Float.parseFloat(n)));}catch(NumberFormatException err){JOptionPane.showMessageDialog(null, "请输入数字", "警告", JOptionPane.ERROR_MESSAGE);}}else if(b==b2){try{t3.setText(String.valueOf(Float.parseFloat(m)-Float.parseFloat(n)));}catch(NumberFormatException err){JOptionPane.showMessageDialog(null, "请输入数字", "警告", JOptionPane.ERROR_MESSAGE);}}else if(b==b3){try{t3.setText(String.valueOf(Float.parseFloat(m)*Float.parseFloat(n)));}catch(NumberFormatException err){JOptionPane.showMessageDialog(null, "请输入数字", "警告", JOptionPane.ERROR_MESSAGE);}}else if(b==b4){try{t3.setText(String.valueOf(Float.parseFloat(m)/Float.parseFloat(n)));}catch(NumberFormatException err){JOptionPane.showMessageDialog(null, "请输入数字", "警告", JOptionPane.ERROR_MESSAGE);}if(Float.parseFloat(n)==0){t3.setText(null);JOptionPane.showMessageDialog(null, "除数不得为0", "警告", JOptionPane.ERROR_MESSAGE);}}else if(b==b5){t1.setText(null);t2.setText(null);t3.setText(null);}elseSystem.exit(0);} public static void main(String args[]) { new lzjjsq(); } }