package com.A;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class CalculatorDemo extends WindowAdapter implements ActionListener
{
int j,p,k,l,m ,i;
JButton b[]=new JButton[10]; //按钮数组
JFrame frame;
JButton Ab,dian,dao,jia,jian,cheng,chu,equ,CE,C,Ba,BF,sq,zf;
JTextField show;
JDialog about;
double getValue,sum;
int length=30;
public CalculatorDemo()
{
frame=new JFrame("计算器");
frame.setSize(270, 210);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container con=frame.getContentPane();
JTextField show=new JTextField(30);
show.setEditable(false);
show.setHorizontalAlignment(JTextField.RIGHT);
con.add(show,BorderLayout.NORTH);
con.add(getmainPanel(),BorderLayout.CENTER);
frame.setResizable(false);
frame.setLocation(300,280);
frame.setVisible(true);
}
public JPanel getmainPanel()
{
JPanel mainPanel=new JPanel();
JPanel upPanel =new JPanel(new GridLayout(1,4,2,2));
Ba=new JButton("Back");
upPanel.add(Ba);
Ba.addActionListener(this);
CE=new JButton("CE");
upPanel.add(CE);
CE.addActionListener(this);
C=new JButton("C");
upPanel.add(C);
C.addActionListener(this);
Ab=new JButton("About");
upPanel.add(Ab);
Ab.addActionListener(this);
about=new JDialog(frame,"关于计算器",true);
about.setLocation(300,300);
JLabel lable=new JLabel("作者：章黎");
about.add(lable,"Center");
about.setSize(250, 100);
about.addWindowListener(this);
upPanel.setVisible(true);
mainPanel.add(upPanel);
JPanel dPanel =new JPanel(new BorderLayout(2,2));
JPanel leftPanel =new JPanel(new GridLayout(4,3,2,3));
for(i=9;i>=0;i--)
{
b[i]=new JButton(String.valueOf(i));
leftPanel.add(b[i]);
b[i].addActionListener(this);
}
JButton zf=new JButton("+/-");
leftPanel.add(zf);
zf.addActionListener(this);
JButton dian=new JButton(".");
dian.addActionListener(this);
leftPanel.add(dian);
leftPanel.setVisible(true);
dPanel.add(leftPanel,BorderLayout.WEST);
JPanel rightPanel =new JPanel(new GridLayout(4,2,2,3));
JButton chu=new JButton("/");
rightPanel.add(chu);
chu.addActionListener(this);
JButton sq=new JButton("sqrt");
rightPanel.add(sq);
sq.addActionListener(this);
JButton cheng=new JButton("*");
rightPanel.add(cheng);
cheng.addActionListener(this);
JButton BF=new JButton("%");
rightPanel.add(BF);
BF.addActionListener(this);
JButton jian=new JButton("-");
rightPanel.add(jian);
jian.addActionListener(this);
JButton dao=new JButton("1/x");
rightPanel.add(dao);
dao.addActionListener(this);
JButton jia=new JButton("+");
rightPanel.add(jia);
jia.addActionListener(this);
JButton equ=new JButton("=");
rightPanel.add(equ);
equ.addActionListener(this);
rightPanel.setVisible(true);
dPanel.add(rightPanel,BorderLayout.CENTER);
dPanel.setVisible(true);
mainPanel.add(dPanel);
mainPanel.setVisible(true);
return mainPanel;
}
public void actionPerformed(ActionEvent e) {
// getValue=Double.parseDouble(show.getText());//记住输入的数
if(e.getSource()==jia)
{
if(k==0)//表示加号没有被触发过
sum=getValue;
if(l==1)//连续触发加号键直接得结果
{
sum+=getValue;
}
setSum();
k++;l=1;p=0;
}
if(e.getSource()==jian)
{
if(k==0)
sum=getValue;
if(l==2)
{
sum-=getValue;
}
setSum();
k++;l=2;p=0;
}
if(e.getSource()==cheng)
{
if(k==0)
sum=getValue;
if(l==3)
{
sum*=getValue;
}
setSum();
k++;l=3;p=0;
}
if(e.getSource()==chu)
{
if(k==0)
sum=getValue;
if(l==4)
{
sum/=getValue;
}
setSum();
k++;l=4;p=0;
}
if(e.getSource()==equ)
{
switch(l)//判断触发了那个运算符后再触发等于号
{
case 1:show.setText(String.valueOf(sum+getValue));break;
case 2:show.setText(String.valueOf(sum-getValue));break;
case 3:show.setText(String.valueOf(sum*getValue));break;
case 4:show.setText(String.valueOf(sum/getValue));break;
}
setSum();
k=0;p=0;l=0;
}
if(e.getSource()==dian)//如果触发按钮"."，是第一次的话允许添加"."并接受后来输入的数
{
if(p==0)
{
show.setText(show.getText()+"."+e.getActionCommand());
}
p=1;
}
if(e.getSource()==C||e.getSource()==CE)//触发按钮还原则显示0
{
k=0;p=0;l=0;sum=0;
show.setText("0");
}
if(e.getSource()==Ab)
{
about.setVisible(true);
}
for(i=9;i>=0;i--)
{
if(e.getSource()==b[i])
{
if(j==0)//触发了等于号后j=0；再输入数时就得清空以前的数
show.setText("");
String s=show.getText();
if(s.length()<length)
{
show.setText(s+e.getActionCommand());
}
if(e.getSource()==b[0]&&getValue==0&&p==0)
{
show.setText("0");
}
if(e.getSource()!=b[0]&&getValue==0&&p==0)//如果第一个数输入的是0第二个数不是则显示第二个数
{
show.setText(e.getActionCommand());
}
j++;
}
}
if(e.getSource()==dao)
{
sum=1/getValue;
setSum();
}
if(e.getSource()==BF)
{
sum=getValue/100;
setSum();
}
if(e.getSource()==sq)
{
sum=getValue*getValue;
setSum();
}
if(e.getSource()==Ba)
{
String s=show.getText();
if(s.length()>1)
{
show.setText("");//清空显示的数用来接收退格以后的数
for(m=0;m<s.length()-1;m++)//用一个循环来显示从0到length-1的位置的字符
{
show.setText(show.getText()+s.charAt(m));
}
}
else
show.setText("0");
}
if(e.getSource()==zf)
{
String s=show.getText();
char a=s.charAt(0);
if(a=='-')
{
show.setText("");
for(m=1;m<s.length();m++)
{
show.setText(show.getText()+s.charAt(m));
}
}
else
show.setText("-"+s);
}
}
public void setSum()
{
show.setText(String.valueOf(sum));
String s=show.getText();
char a=s.charAt(s.length()-1);
char b=s.charAt(s.length()-2);
if(a=='0'&&b=='.')
{
// show.setText(String.valueOf(Math.round(sum)));
show.setText(s.substring(0, s.length()-2));
}
}
public void windowClosing(WindowEvent e){
if(e.getSource()==about)
about.setVisible(false);
else if(e.getSource()==frame)
System.exit(0);
}
public static void main(String []args)
{
new CalculatorDemo();
}
}为什么触发数字键就有错误啊 ！！怎么想也不明白！
[b]问题补充：[/b]
我的show 不new 了吗？也添加到frame 上啦
