package com.test4;import java.awt.*;
import java.awt.event.*;import javax.swing.*;public class Test {public static void main(String[] args) {Calculator_Frame cf = new Calculator_Frame();}}class Calculator_Frame extends JFrame implements ActionListener {boolean readyNextNumber = true;double number1 = 0;double number2 = 0;char op = '\0';JLabel jl;JPanel jp;JButton jb_1, jb_2, jb_3, jb_4, jb_5, jb_6, jb_7, jb_8, jb_9, jb_0, jb_jia,jb_jian, jb_cheng, jb_chu, jb_dian, jb_deng;String str;Calculator_Frame() {jl = new JLabel("0.0", JLabel.RIGHT);jl.setFont(new Font("Dialog", 1, 17));jp = new JPanel(new GridLayout(4, 4));jb_0 = new JButton("0");jb_9 = new JButton("9");jb_1 = new JButton("1");jb_2 = new JButton("2");jb_3 = new JButton("3");jb_4 = new JButton("4");jb_5 = new JButton("5");jb_6 = new JButton("6");jb_7 = new JButton("7");jb_8 = new JButton("8");jb_jia = new JButton("+");jb_jian = new JButton("-");jb_cheng = new JButton("*");jb_chu = new JButton("/");jb_deng = new JButton("=");jb_dian = new JButton(".");jb_0.addActionListener(this);jb_1.addActionListener(this);jb_2.addActionListener(this);jb_3.addActionListener(this);jb_4.addActionListener(this);jb_5.addActionListener(this);jb_6.addActionListener(this);jb_7.addActionListener(this);jb_8.addActionListener(this);jb_9.addActionListener(this);jb_jia.addActionListener(this);jb_jian.addActionListener(this);jb_cheng.addActionListener(this);jb_chu.addActionListener(this);jb_dian.addActionListener(this);jb_deng.addActionListener(this);jp.add(jb_1);jp.add(jb_2);jp.add(jb_3);jp.add(jb_jia);jp.add(jb_4);jp.add(jb_5);jp.add(jb_6);jp.add(jb_jian);jp.add(jb_7);jp.add(jb_8);jp.add(jb_9);jp.add(jb_cheng);jp.add(jb_0);jp.add(jb_dian);jp.add(jb_deng);jp.add(jb_chu);this.add(jl, BorderLayout.NORTH);this.add(jp, BorderLayout.CENTER);this.setBounds(100, 10, 200, 300);this.setDefaultCloseOperation(3);this.setVisible(true);}public void actionPerformed(ActionEvent e) {str = e.getActionCommand();// 获取按钮上的字符串// 判断是否点击的数字if (str.equals("0") || str.equals("1") || str.equals("2")|| str.equals("3") || str.equals("4") || str.equals("5")|| str.equals("6") || str.equals("7") || str.equals("8")|| str.equals("9") || str.equals(".")) {if (readyNextNumber) {// 判断是否想输入一个新数字jl.setText(str);readyNextNumber = false;} else {jl.setText(jl.getText() + str);// 把label上的字符串加上刚刚点击的字符串}// 判断是否点击的操作符} else if (str.equals("+")) {readyNextNumber = true;if(op == '\0'){number1 = Double.parseDouble( jl.getText());}else{number2 = Double.parseDouble( jl.getText());jl.setText(count()+"");number1 = count();}op = '+';}else if(str.equals("-")){readyNextNumber = true;if(op == '\0'){number1 = Double.parseDouble( jl.getText());}else{number2 = Double.parseDouble( jl.getText());jl.setText(count()+"");number1 = count();}op = '-';}else if(str.equals("*")){readyNextNumber = true;if(op == '\0'){number1 = Double.parseDouble( jl.getText());}else{number2 = Double.parseDouble( jl.getText());jl.setText(count()+"");number1 = count();}op = '*';}else if(str.equals("/")){readyNextNumber = true;if(op == '\0'){number1 = Double.parseDouble( jl.getText());}else{number2 = Double.parseDouble( jl.getText());jl.setText(count()+"");number1 = count();}op = '/';}else if(str.equals("=")){readyNextNumber = true;number2 = Double.parseDouble( jl.getText());jl.setText(count()+"");op = '\0';}}public double count(){double result = 0;switch (op) {case '+':result= number1 + number2;break;case '-':result=number1 - number2;break;case '*':result=number1 * number2;break;case '/':result=number1 / number2;break;default:break;}return  result;}}