Java实现简单的计算器（原创）

女爷i 2023-08-17 15:51 166阅读 0赞

初学Java中的Swing,写了一个简单的计算器，和大家分享一下！![e113.gif][]

支持键盘和鼠标操作

支持多个数运算。例如：输入1+2+3，结果是6！

源代码：

import java.awt.\*; import javax.swing.\*; import java.awt.event.\*; class GUI extends JFrame implements ActionListener,KeyListener \{ JTextField textField; private String strx = ""; private String stry =""; private String str =""; private String op=""; private String result=""; private int flag=1; private String strtemp; private float x; private float y; public GUI() \{ super(); this.setTitle("计算器"); this.setVisible(true); this.setBounds(800, 400, 280, 250); this.setResizable(true); this.addKeyListener(this); BorderLayout borLayout = new BorderLayout(); this.getContentPane().setLayout(borLayout); final JPanel viewpanel = new JPanel(); this.getContentPane().add(viewpanel, BorderLayout.NORTH); textField = new JTextField(); textField.setEditable(false); textField.setText("0"); textField.setHorizontalAlignment(SwingConstants.RIGHT); textField.setColumns(20); viewpanel.add(textField); final JPanel bottonPanel = new JPanel(); bottonPanel.setSize(200, 200); GridLayout gri = new GridLayout(4,0); gri.setHgap(10); gri.setVgap(10); bottonPanel.setLayout(gri); String\[\]\[\] names =\{ \{"1","2","3","+"\}, \{"4","5","6","-"\}, \{"7","8","9","\*"\}, \{".","0","=","/"\} \}; JButton\[\]\[\] buttons = new JButton\[4\]\[4\]; for(int i=0;i<4;i++) \{ for(int j=0;j<4;j++) \{ buttons\[i\]\[j\] = new JButton(names\[i\]\[j\]); buttons\[i\]\[j\].setName(names\[i\]\[j\]); buttons\[i\]\[j\].setSize(40, 35); buttons\[i\]\[j\].addActionListener(this); bottonPanel.add(buttons\[i\]\[j\]); \} \} this.getContentPane().add(bottonPanel,BorderLayout.CENTER); final JLabel label1 = new JLabel(); label1.setPreferredSize(new Dimension(10,0)); this.getContentPane().add(label1,BorderLayout.WEST); final JButton button = new JButton("CE"); button.setName("CE"); button.addActionListener(this); this.getContentPane().add(button,BorderLayout.EAST); \} public void calculate() \{ if(str!="") \{ System.out.println("strx == "+strx); System.out.println("stry == "+stry); try\{ if(strx=="") \{ strx=strtemp; \} x=Float.parseFloat(strx); y=Float.parseFloat(stry); \}catch(Exception ex) \{ ex.printStackTrace(); \} if(op=="+") \{ result = (x + y) + ""; \} else if(op=="-") \{ result = (x - y) + ""; \}else if(op=="\*") \{ result = (x \* y) + ""; \}else \{ if(y==0) \{ result="ERROR"; \} else\{ result = (x / y) + ""; \} \} \} \} private void CaculateTemp() \{ if(op=="\*"||op=="+"||op=="-"||op=="/") \{ calculate(); strx=result; str=result; stry=""; \} \} private void CE() \{ strx = ""; stry =""; str =""; op=""; result=""; flag=1; textField.setText("0"); \} private void Cacu(String s) \{ if(s.equals("CE")) \{ CE(); \} else if(s.equals("=")) \{ calculate(); textField.setText(result); strtemp=result; str=strtemp; stry=""; op=""; \} else \{ if(s.equals("+")) \{ if(result!="") \{ str=result; strx=result; \} CaculateTemp(); flag=0; op="+"; \}else if(s.equals("-")) \{ if(result!="") \{ str=result; strx=result; \} CaculateTemp(); flag=0; op="-"; \}else if(s.equals("\*")) \{ if(result!="") \{ str=result; strx=result; \} CaculateTemp(); flag=0; op="\*"; \}else if(s.equals("/")) \{ if(result!="") \{ str=result; strx=result; \} CaculateTemp(); flag=0; op="/"; \}else \{ if(flag==1) \{ strx = strx + s; System.out.println("strx = "+strx); \} if(flag==0) \{ stry = stry + s; System.out.println("stry = "+stry); \} \} str = str + s; System.out.println("str = "+str); textField.setText(str); \} \} public void actionPerformed(ActionEvent e) public void keyTyped(KeyEvent e) public void keyReleased(KeyEvent e) public void keyPressed(KeyEvent e) \} public class JSQ \{ public static void main(String\[\] args) \{ GUI a = new GUI(); \} \}

经过本人多次调试，此程序中仍然存在问题。

1、不能先输入等号

2、不能连续输入多个操作符

3、进行每次运算的时候，都要先清零！

4、运行的时候，出现的窗口要先最小化，再打开，才能显示（不知道为什么）

5、支持键盘和鼠标操作，但是如果一用鼠标操作，就不能再用键盘操作了！（个人觉得，可能监听器加的位置有问题，但又不知道该加到那里可以让键盘，鼠标操作随意切换）

6、可能还有其他问题，所以此处略去n个字！！！！！！

![b.gif][]

转载于:https://www.cnblogs.com/JPAORM/archive/2011/05/10/2510104.html

[e113.gif]: http://edu.qzs.qq.com/qzone/em/e113.gif
[b.gif]: http://edu.qzs.qq.com/ac/b.gif