JAVA中用GUI编程.doc

JAVA中用GUI编程实现计算器模拟 摘 要对计算器程序进行需求分析、概要设计、详细设计，最后使用Java编程实现的全过程。设计GUI界面的计算器用户可以通过鼠标依次输入参加计算的数值，进行加、减、乘、除关键词：GridLayout（网格布局）对数字控件和操作按钮进行布局。此外，单击任何一个按钮都会触发ActionEvent事件，要处理这些事件就必须实现ActionListener接口的actionPerformed方法。 二．程序代码如下 import javax.swing.*; import javax.swing.event.*; import java.awt.*; import java.awt.event.*; //变量设置如下 //继承JFrame类并实现ActionListenter接口 public class calculator extends JFrame implements ActionListener { JFrame frame; //数字及操作按钮 JButton num0,num1,num2,num3,num4,num5,num6,num7,num8,num9,Back,c; //运算按钮 JButton plusButton,minusButton,multiplyButton,divideButton,residueButton,equalButton,changeButton,dotButton,sqrtButton,reciprocalButton; JMenu fileM; JMenuItem exitM,helpM; JTextField text; //状态变量 boolean clicked=true; boolean clear=true; int all=0; double previous; String fuhao; int first=1; //界面设计 public calculator(){ setTitle(计算器); setSize(300,250); setLocation(400,400); text=new JTextField(25); text.setHorizontalAlignment(JTextField.LEFT); JPanel cp1=new JPanel(); JPanel cp2=new JPanel(); JPanel cp3=new JPanel(); //设置整体布局 getContentPane().add(cp1,North); getContentPane().add(cp2,Center); getContentPane().add(cp3,South); cp1.setLayout(new GridLayout(1,1)); cp2.setLayout(new GridLayout(1,2)); cp3.setLayout(new GridLayout(5,4)); plusButton=new JButton(+);//加 minusButton=new JButton(-);//减 multiplyButton=new JButton(*);//乘 divideButton=new JButton(/);//除 residueButton=new JButton(%);//余数 equalButton=new JButton(=);//等号 changeButton=new JButton(+/-);//正负号切换 dotButton=new JButton(.);//小数点 sqrtButton=new JButton(sqrt);//开方 reciprocalButton=new JButton(1/x);//倒数 //数字按钮 num0=new JButton(0); num1=new JButton(1); num2=new JButton(2); num3=new JButton(3); num4=new JButton(4); num5=new JButton(5); num6=new JButton(6); num7=new JButton(7); num8=new JButton(8); num9=new JButton(9); cp1.add(text); text.setEditable(false); text.setBackground(Color.white); //监听设置 Back=new JButton(Back); Back.addActionListener(this); c=new JBut