java图形界面UI设计——简单的计算器

import javax.swing.*;
Copyright vivi_and_qiao liwei
import java.awt.*;
import java.util.*;
import java.lang.*;
import java.awt.event.*; 
public class GridBagcalc implements MouseListener{
private JFrame jf;
private JButton []jb;
private JTextField jtf;
public StringBuffer s1=new StringBuffer();
public StringBuffer s2=new StringBuffer();
public StringBuffer s3=new StringBuffer();
private double result=0;
private double source=0;
private double dest = 0;
private char temp = '?';
int signal=0;
public void go()
{  String []s;
jf=new JFrame("the demonstration of calculator");
Container cp=jf.getContentPane();
GridBagLayout gl=new GridBagLayout();
cp.setLayout(gl);
   GridBagConstraints c=new GridBagConstraints();
   jb=new JButton[15];
   for(int i=1;i<=9;i++)
   {
   jb[i-1]=new JButton(""+(i-1));
   c.fill=GridBagConstraints.VERTICAL;
   if(i<4)
    c.gridy=0;
   else if(i<7)
    c.gridy=1;
   else
    c.gridy=2;
   if(i%3==0)
    c.gridx=2;
   else if(i%3==1)
    c.gridx=0;
   else if(i%3==2)
    c.gridx=1;
        gl.setConstraints(jb[i-1],c);
        cp.add(jb[i-1]);
   }
   jb[9]=new JButton("+");
   jb[10]=new JButton("-");
   jb[11]=new JButton("*");
   jb[12]=new JButton("/");
   jb[13]=new JButton("=");
   jb[14]=new JButton("AC");
   c.gridx=0;c.gridy=4;
   gl.setConstraints(jb[9], c);
   c.fill=GridBagConstraints.VERTICAL;
   cp.add(jb[9]);
   c.gridx=1;c.gridy=4;
   gl.setConstraints(jb[10], c);
   c.fill=GridBagConstraints.VERTICAL;
   cp.add(jb[10]);
   c.gridx=2;c.gridy=4;gl.setConstraints(jb[11], c); 
   c.fill=GridBagConstraints.VERTICAL;
   cp.add(jb[11]);
   c.gridx=3;c.gridy=4;gl.setConstraints(jb[12], c);
   c.fill=GridBagConstraints.VERTICAL;
   cp.add(jb[12]);
   c.gridx=5;c.gridy=4;gl.setConstraints(jb[13], c);
   cp.add(jb[13]);
   c.gridx=0;c.gridy=5;gl.setConstraints(jb[14], c);
   cp.add(jb[14]);
   jtf=new JTextField(9);
   jtf.setText("0.0");
   c.gridx=5;c.gridy=0;
   cp.add(jtf,c);
   jf.setSize(20, 30);
   jf.setVisible(true);
   jf.addMouseListener(this);
   for(int i=0;i<15;i++)
    jb[i].addMouseListener(this);
}
public static void main(String []args)
{
GridBagcalc calc=new GridBagcalc();
calc.go();
}
@Override
public void mouseClicked(MouseEvent e) {
// TODO 自动生成的方法存根

}
@Override
public void mousePressed(MouseEvent e) {
// TODO 自动生成的方法存根
if(temp=='?')
{ for(int i=0;i<9;i++)
if(e.getSource()==jb[i])
{
if(signal==0)
s1.append(String.valueOf(i));
else
{
s1.delete(0,s1.length());s1.append(source);signal=0;
}
jtf.setText(s1.toString());
source=Double.valueOf(s1.toString());
System.out.println("source"+source);
}
}
if(e.getSource()==jb[9])
{
temp='+';
jtf.setText(s3.append(source+"+").toString());
}
if(e.getSource()==jb[10])
{ jtf.setText(s3.append(source+"-").toString());temp='-';
}
if(e.getSource()==jb[11])
{ temp='*';
jtf.setText(s3.append(source+"*").toString());
}
if(e.getSource()==jb[12])
{jtf.setText(s3.append(source+"/").toString());temp='/';
}
System.out.println("temp:"+temp);
if(temp!='?')
{
for(int i=0;i<9;i++)
if(e.getSource()==jb[i])
{
s2.append(i);
jtf.setText(s3.append(String.valueOf(i)).toString());
dest=Double.valueOf(s2.toString());
System.out.println("dest:"+dest);}
       }
if(e.getSource()==jb[13])
{
switch(temp){
case'+':result=source+dest;break;
case'-':result=source-dest;break;
case'*':result=source*dest;break;
case'/':result=source/dest;break;
}
System.out.println("source:"+source+"dest:"+dest+"result:"+result);
jtf.setText(String.valueOf(result).toString());
source=result;
temp='?';
dest=0;
signal=1;
s3.delete(0,s3.length());
s2.delete(0,s2.length());
}
if(e.getSource()==jb[14])
{source=dest=result=0;temp='?';signal=0;jtf.setText("0.0");
s1.delete(0, s1.length());
s2.delete(0, s1.length());
s3.delete(0, s1.length());
}
}
@Override
public void mouseReleased(MouseEvent e) {
// TODO 自动生成的方法存根

}
@Override
public void mouseEntered(MouseEvent e) {
// TODO 自动生成的方法存根

}
@Override
public void mouseExited(MouseEvent e) {
// TODO 自动生成的方法存根

}
}