用java编写简单计算器.doc

用java写了一个简单计算器，能实现简单的数据计算。一、 先写界面代码： 在UI包里面新建一个Class文件，取名自己想，这里我写的是CalculatorFramepackage ui;import java.awt.Color;import java.awt.Font;import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.border.TitledBorder;public class CalculatorFrame extends JFrame private static final long serialVersionUID = 1L;public String opt;public String str;private JTextArea show;private ClientContext clientContext;/引用控制器对象 /*因为调用了控制器里面的方法，所以要对控制器的对象进行赋值，否则运行会出现空指针异常*/public void setClientContext(ClientContext clientContext) this.clientContext = clientContext;public CalculatorFrame() init();private void init() setTitle( Simple Calculator);setBounds(533, 184, 300, 400);setContentPane(creatContentPane();private JPanel creatContentPane() JPanel p = new JPanel(new GridLayout(4, 1);/* 在面板里面添加4个面板*/p.add(showPane();/显示屏p.add(btnPane1();/下面三个都是按钮p.add(btnPane2();p.add(btnPane3();return p;/*实现各个面板*/private JScrollPane showPane() JScrollPane p = new JScrollPane();p.setBorder(new TitledBorder(Display:);show = new JTextArea();show.setFont(new Font(,Font.PLAIN,25);show.setForeground(Color.RED);show.setLineWrap(true);show.setEditable(false);p.getViewport().add(show);return p;private JPanel btnPane1() JPanel p = new JPanel(new GridLayout(2, 4);JButton add = new JButton(+);JButton jian = new JButton(-);JButton cheng = new JButton(*);JButton chu = new JButton(/);JButton one = new JButton(1);JButton two = new JButton(2);JButton three = new JButton(3);JButton anser = new JButton(=);p.add(add);p.add(jian);p.add(cheng);p.add(chu);p.add(one);p.add(two);p.add(three);p.add(anser);/*用内部类实现按钮监视器，后面的都是这样*/one.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent arg0) String number = show.getText() + String.valueOf(1);/按了数字“1”按/钮后，操作显示屏,既更新一下显示屏clientContext.setNumber(number);/调用控制器里面的方法);two.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent arg0) String number = show.getText() + String.valueOf(2);clientContext.setNumber(number););three.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(3);clientContext.setNumber(number););add.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent arg0) opt = +;clientContext.setOpt(opt););jian.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubopt = -;clientContext.setOpt(opt););cheng.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubopt = *;clientContext.setOpt(opt););chu.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubopt = /;clientContext.setOpt(opt););anser.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent arg0) str = =;clientContext.setAnswer(str););return p;private JPanel btnPane2() JPanel p = new JPanel(new GridLayout(2, 4);JButton four = new JButton(4);JButton five = new JButton(5);JButton six = new JButton(6);JButton pi = new JButton(PI);JButton seven = new JButton(7);JButton eight = new JButton(8);JButton nine = new JButton(9);JButton com = new JButton(.);p.add(four);p.add(five);p.add(six);p.add(pi);p.add(seven);p.add(eight);p.add(nine);p.add(com);four.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(4);clientContext.setNumber(number););five.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(5);clientContext.setNumber(number););six.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(6);clientContext.setNumber(number););seven.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(7);clientContext.setNumber(number););eight.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(8);clientContext.setNumber(number););nine.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(9);clientContext.setNumber(number););com.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubsetShow(show.getText() + .););pi.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubsetShow(String.valueOf(Math.PI););return p;private JPanel btnPane3() JPanel p = new JPanel(new GridLayout(2, 4);JButton zero = new JButton(0);JButton sqrt = new JButton();JButton guiling = new JButton(C);final JButton help = new JButton(Help);p.add(zero);p.add(sqrt);p.add(guiling);p.add(help);help.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubJOptionPane.showMessageDialog(help, 注意：假如第二运算数为空的话，这里将默认为0.0！););guiling.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubclientContext.setMc(););zero.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubString number = show.getText() + String.valueOf(0);clientContext.setNumber(number););sqrt.addActionListener(new ActionListener() Overridepublic void actionPerformed(ActionEvent e) / TODO Auto-generated method stubsetShow( + Math.sqrt(getShow(););return p;/*更新计算器的显示屏*/public void setShow(String str) show.setText(str);/*获取当前显示屏里面的数据*/public Double getShow() String str = show.getText();if (str.equals() str = 0.0;return Double.valueOf(str);/*获取当前选择的运算符：比如加或减或乘或除*/public String getOpt() return this.opt;二、 写控制器代码在UI包建立一个Class，我取名ClientContextpackage ui;import java.util.ArrayList;import java.util.List;import javax.swing.JOptionPane;public class ClientContext private CalculatorFrame calculatorFrame;private Double first = 0.0;private Double next = 0.0;public void setCalculatorFrame(CalculatorFrame calculatorFrame) this.calculatorFrame = calculatorFrame;double sum = 0;public void setNumber(String str) calculatorFrame.setShow(str);public void setOpt(String opt) first = calculatorFrame.getShow();calculatorFrame.setShow();public void setAnswer(String str) /按了“=”后，对数据按运算符进行计算next = calculatorFrame.getShow();/ calculatorFrame.setShow(str);/switch(str)/if (calculatorFrame.getOpt() = +) double answer = first + next;calculatorFrame.setShow(String.valueOf(answer); else if (calculatorFrame.getOpt() = -) double answer = first - next;calculatorFrame.setShow(String.valueOf(answer); else if (calculatorFrame.getOpt() = *) double answer = first * next;calculatorFrame.s