java编写的计算器GUI程序

1、package example;import java.awt.*;import java.awt.event.*;public class Calculator extends Frame /* * 本实例实现功能如下 1.普通加减乘除运算 2.小数点的情况已经解决 3.开始按0已经解决 4.消去键可以起作用 * * author 血怒樱花 * QQ:108543911 */private static final long serialVersionUID = 1L;private String name = "0", "1", "2&qu

2、ot;, "3", "4", "5", "6", "7", "8", "9",".", "=", "+", "-", "*", "/", "Backspace", "", "", "C" ;private Button button = new Buttonn

3、ame.length;private TextField textfield = new TextField("0.");/ 设置2个字符A1,A2用于存放点击运算符号之前的String数据private String A1 = null, A2 = null;/ 设置2个字符B1,B2用于存放点击运算符号之后的String数据private String B1 = null, B2 = null;/ 存放运算符号前后的数据，douuble类型进行运算private double A, B;/ s存放为哪种运算符号，Result存放最后的运行结果private String

4、 Result="0", s;/ 判断这个数字是否为小数，小数的时为true不是时为falseprivate boolean Decimal=false;/ 构造器，显示在标题栏public Calculator() super("TEST:Caculator");/ 计算器的基本布局，在一个BorderLayout上面放置了一个GridLayout一个BorderLayoutpublic void init() setLayout(new BorderLayout(2, 2);/ 设置2个PanelPanel p0 = new Panel();Pane

5、l p1 = new Panel();/ p0上添加所有按扭p0.setLayout(new GridLayout(5, 4, 1, 1);/ 不同的按扭采用不同的监听事件0-9和"."采用ButtonListener()for (int i = 0; i < 11; i+) buttoni = new Button(namei);/ 设置字体颜色为蓝色buttoni.setForeground(Color.blue);p0.add(buttoni);buttoni.addActionListener(new ButtonListener();/ 其余的运算符号采取B

6、uttonListener2()另一监听事件for (int i = 11; i < name.length; i+) buttoni = new Button(namei);/ 设置字体颜色为红色buttoni.setForeground(Color.RED);p0.add(buttoni);buttoni.addActionListener(new ButtonListener2();/ 设置中间2个按扭不可见，增加美观,对称button17.setVisible(false);button18.setVisible(false);/ p1上添加文本输出区域p1.setLayout(

7、new BorderLayout(5, 5);p1.add(textfield);/ 不可以向文本框里随便写东西textfield.setEditable(false);/ 设置文本框背景为白色textfield.setBackground(Color.WHITE);add(p0, BorderLayout.SOUTH);add(p1, BorderLayout.NORTH);pack();/ 设置打开窗口在显示器的中间显示setLocationRelativeTo(null);/ 关闭按扭，适配器模式addWindowListener(new WindowAdapter() public v

8、oid windowClosing(WindowEvent e) System.exit(0););/ 调整可见setVisible(true);public class ButtonListener implements ActionListener public void actionPerformed(ActionEvent e) System.out.print(e.getActionCommand() + " ");/ 当A2和B2同时为null时候表示程序第一次运行或者开始一次新的运行,即按"="之后,将按键获取的值赋给A2-setp1if

9、(A2 = null && B2 = null) / 所按的数字按扭不是"0"的时候对A2进行赋值,否则给A2值不变，但是让textfield恢复初始值"0."if (!"0".equals(e.getActionCommand() / 考虑第一次按小数点的情况,按小数点后将boolean类型的Decimal定义为trueif (".".equals(e.getActionCommand() A2 = "0."Decimal = true;textfield.setText(A2

10、); else A2 = e.getActionCommand();textfield.setText(A2); else if ("0".equals(e.getActionCommand() else A2 = e.getActionCommand();textfield.setText("0");/ 当A2不等于null,B2和A为null,表示还没有按运算符号，仍然对A2进行赋值 else if (A2 != null && A1 = null && B2 = null) / 已经是小数的在点小数点不做任何动作，不

11、是小数的在按"."的时候追加赋值并且设置Decimal为trueif (".".equals(e.getActionCommand() if (Decimal) else Decimal = true;A2 += e.getActionCommand();textfield.setText(A2); else A2 += e.getActionCommand();textfield.setText(A2);/ 当A,A2不等于null,B2为null,表示刚按过运算符号，开始对B2进行赋值/ 仍要考虑"0"的情况，但要考虑0做为被减数

12、，乘数和加数，此处B2可以等于0/ B2也可以是小数将Decimal设置回false else if (A2 != null && A1 != null && B2 = null) Decimal = false;if (!"0".equals(e.getActionCommand() / 不为"0"但为"."的情况,原理同上if (".".equals(e.getActionCommand() Decimal = true;if (Decimal) B2 = "0.&qu

13、ot; else Decimal = true;B2 = e.getActionCommand();textfield.setText(B2); else B2 = e.getActionCommand();textfield.setText(B2); else B2 = "0"textfield.setText(B2);/ 当A,A2,B2都不为null的时候表示B2已经被赋值，继续按数字按扭对B2继续赋值/ 当B2等于0的时候不进行追加直接赋值，仅当B2不等于0的时候才进行追加 else if (A2 != null && A1 != null &

14、;& B2 != null) if ("0".equals(B2) / 考虑用户连续2次按"0"的情况if ("0".equals(e.getActionCommand() B2 = "0"textfield.setText(B2); else B2 = e.getActionCommand();textfield.setText(B2); else / 不为"0"但为"."的情况,原理同上if (".".equals(e.getActionCom

15、mand() if (Decimal) else Decimal = true;B2 += e.getActionCommand();textfield.setText(B2); else B2 += e.getActionCommand();textfield.setText(B2);public class ButtonListener2 implements ActionListener public void actionPerformed(ActionEvent e) System.out.print(e.getActionCommand() + " ");/ 一

16、旦按了运算符号"+-*/"A2赋值给A，使得A和A2都不为null,但此时B2还为null在按数字键的时候便会给B2赋值/ 给s-运算符号赋值if ("+".equals(e.getActionCommand() if (A2 = null) A2 = "0"A1 = A2;s = "+" else if ("-".equals(e.getActionCommand() if (A2 = null) A2 = "0"A1 = A2;s = "-" else

17、 if ("*".equals(e.getActionCommand() if (A2 = null) A2 = "0"A1 = A2;s = "*" else if ("/".equals(e.getActionCommand() if (A2 = null) A2 = "0"A1 = A2;s = "/"/ 等号的时候把B2赋值给B，进行最后的运算 else if ("=".equals(e.getActionCommand() if (A2 = nu

18、ll) A2 = "0"if (B2 = null) B2 = "0"A1 = A2;B1 = B2;/ 将String类型转换为double进行运算A = Double.parseDouble(A1);B = Double.parseDouble(B1);if ("+".equals(s) Result = String.valueOf(A + B);System.out.println();System.out.println(A + "+" + B + "=" + Result); els

19、e if ("-".equals(s) Result = String.valueOf(A - B);System.out.println();System.out.println(A + "-" + B + "=" + Result); else if ("*".equals(s) Result = String.valueOf(A * B);System.out.println();System.out.println(A + "*" + B + "=" + Result

20、);textfield.setText(Result);A1 = null;A2 = null;B1 = null;B2 = null;Decimal=false; else if ("Backspace".equals(e.getActionCommand() String text = "0"if (A2 = null && A1 = null) else if (A2 != null && A1 = null && B2 = null) int t = A2.length();text = A2;if (t = 1) text = "0" else text = text.substring(0, t - 1);A2 = text; else