用java語言編寫一個(gè)計(jì)算器有代碼并有詳解？
下面文件名要為：
JiSuanQi.java
import java.awt.*;
import java.awt.event.*;
public class JiSuanQi
{
String s="",s1=null,s2=null;
Frame f=new Frame("計(jì)算器");
TextField tf=new TextField(30);
Panel p1=new Panel();
Panel p2=new Panel();
Panel p3=new Panel();
Button bt1=new Button("=");
Button bt2=new Button("刪除");
Button[] bt=new Button[16];
int id=0;
public static void main(String[] args)
{
new JiSuanQi().init();
}
public void init()
{
f.setBackground(new Color(85,247,253));
f.setLayout(new BorderLayout(4,4));
p2.setLayout(new GridLayout(4,4,4,4));
p3.setLayout(new BorderLayout(4,4));
f.setResizable(false);
f.add(p1,BorderLayout.NORTH);
f.add(p2);
p3.add(bt2,BorderLayout.NORTH);
p3.add(bt1);
p1.add(tf);
f.add(p3,BorderLayout.EAST);
String[] b={"1","2","3","+","4","5","6","-","7","8","9","*","0",".","復(fù)位","/"};
for(int i=0;i<16;i++)
{
bt[i]=new Button(b[i]);
p2.add(bt[i]);
}
bt[0].setForeground(Color.blue);
bt[1].setForeground(Color.blue);
bt[2].setForeground(Color.blue);
bt[4].setForeground(Color.blue);
bt[5].setForeground(Color.blue);
bt[6].setForeground(Color.blue);
bt[8].setForeground(Color.blue);
bt[9].setForeground(Color.blue);
bt[10].setForeground(Color.blue);
bt[12].setForeground(Color.blue);
bt[13].setForeground(Color.blue);
bt[3].setForeground(Color.red);
bt[7].setForeground(Color.red);
bt[11].setForeground(Color.red);
bt[15].setForeground(Color.red);
bt[14].setForeground(Color.red);
bt1.setForeground(Color.red);
bt2.setForeground(Color.red);
f.pack();
f.setVisible(true);
f.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
bt[0].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=1;
s2+=1;
tf.setText(s);
}
}
);
bt[1].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=2;
s2+=2;
tf.setText(s);
}
}
);
bt[2].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=3;
s2+=3;
tf.setText(s);
}
}
);
bt[4].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=4;
s2+=4;
tf.setText(s);
}
}
);
bt[5].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=5;
s2+=5;
tf.setText(s);
}
}
);
bt[6].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=6;
s2+=6;
tf.setText(s);
}
}
);
bt[8].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=7;
s2+=7;
tf.setText(s);
}
}
);
bt[9].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=8;
s2+=8;
tf.setText(s);
}
}
);
bt[10].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=9;
s2+=9;
tf.setText(s);
}
}
);
bt[12].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+=0;
s2+=0;
tf.setText(s);
}
}
);
bt[13].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s+='.';
s2+='.';
tf.setText(s);
}
}
);
bt[3].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s1=s;
s+='+';
id=1;
s2="";
tf.setText(s);
}
}
);
bt[7].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s1=s;
s+='-';
id=2;
s2="";
tf.setText(s);
}
}
);
bt[11].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s1=s;
s+='*';
id=3;
s2="";
tf.setText(s);
}
}
);
bt[14].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s="";
s2="";
tf.setText(s);
}
}
);
bt[15].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
s1=s;
s+='/';
id=4;
s2="";
tf.setText(s);
}
}
);
bt1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(id<1) ;
else{
s+='=';
Double a=Double.parseDouble(s1);
double b=Double.parseDouble(s2);
double c=0;
switch(id)
{
case 1:c=a+b; break;
case 2:c=a-b; break;
case 3:c=a*b; break;
case 4:c=a/b; break;
}
s+=c;
tf.setText(s);
}
s="";s1="";s2="";id=0;
}
}
);
bt2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
char[] c1;
char[] c2=new char[s.length()-1];
c1=s.toCharArray();
for(int i=0;i<s.length()-1;i++)
c2[i]=c1[i];
s=s.valueOf(c2);
if(id<1)
{
s1=s;
}
if(s2.length()>=1)
{
char[] c3;
char[] c4=new char[s2.length()-1];
c3=s2.toCharArray();
for(int i=0;i<s2.length()-1;i++)
c4[i]=c3[i];
s2=s2.valueOf(c4);
}
tf.setText(s);
}
}
);
}
}
