简单功能的计算器

作为初学者总想写点可行的东西， 但是总也是四处碰壁！

要知道，只有在逆境中才能磨练自己！

自信点，勇于去面对错误，找出原因，就是进步！

 

 

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class JSanQi implements ActionListener {
 JFrame f1;

 JPanel p1, p2, p3;

 JTextField t1;

 JButton bt[];

 JButton bdoc, bexit, back, bzero, badd, bsub, bmul, bdiv, bcanl, bequl;

 boolean Key;

 JMenuBar menu;

 JMenu m1;

 JMenuItem mt1, mt2;

 Double fnum;

 int key, doc;

 @SuppressWarnings("deprecation")
 public JSanQi() {
  fnum = 0.0;
  Key = true;
  doc = 0;
  f1 = new JFrame("My Calculator!");
  f1.setLayout(new BorderLayout());
  p1 = new JPanel();
  p2 = new JPanel();
  p3 = new JPanel();
  t1 = new JTextField();
  menu = new JMenuBar();
  m1 = new JMenu("file");
  mt1 = new JMenuItem("nihao!");
  mt2 = new JMenuItem("exit!");
  t1.setEditable(false);
  t1.setBackground(new Color(205,201,120));
  f1.add(p2, BorderLayout.NORTH);
  f1.add(p1);
  p2.setLayout(new FlowLayout());
  p2.add(menu, FlowLayout.LEFT);
  menu.add(m1);
  m1.add(mt1);
  m1.add(mt2);
  mt1.addActionListener(this);
  mt2.addActionListener(this);
  p1.setLayout(new BorderLayout());
  p1.add(t1, BorderLayout.NORTH);
  p1.add(p3);
  bt = new JButton[10];
  for (int i = 0; i < 10; i++) {
   bt[i] = new JButton(Integer.toString(i));
  }
  bdoc = new JButton(".");
  bexit = new JButton("Exit!");
  back = new JButton("Back!");
  back.setForeground(new Color(255, 0, 0));
  bexit.setForeground(new Color(0, 0, 255));
  bexit.setBackground(new Color(120,120,225));
  bzero = new JButton("00");
  badd = new JButton("+");
  bsub = new JButton("-");
  bmul = new JButton("*");
  bdiv = new JButton("/");
  bcanl = new JButton("EC");
  bequl = new JButton("=");
  //bequl.setLabel("123");
  //bequl.addNotify();
  p3.setLayout(new GridLayout(4, 5));

  p3.add(bt[1]);
  p3.add(bt[2]);
  p3.add(bt[3]);
  p3.add(badd);
  p3.add(bsub);
  p3.add(bt[4]);

  p3.add(bt[5]);
  p3.add(bt[6]);
  p3.add(bmul);
  p3.add(bdiv);
  p3.add(bt[7]);
  p3.add(bt[8]);
  p3.add(bt[9]);
  p3.add(back);
  p3.add(bequl);
  p3.add(bt[0]);
  p3.add(bzero);
  p3.add(bdoc);
  p3.add(bcanl);
  p3.add(bexit);

  bt[0].addActionListener(this);
  bt[1].addActionListener(this);
  bt[2].addActionListener(this);
  bt[3].addActionListener(this);
  bt[4].addActionListener(this);
  bt[5].addActionListener(this);
  bt[6].addActionListener(this);
  bt[7].addActionListener(this);
  bt[8].addActionListener(this);
  bt[9].addActionListener(this);

  bdoc.addActionListener(this);
  bexit.addActionListener(this);
  back.addActionListener(this);
  bzero.addActionListener(this);
  badd.addActionListener(this);
  bsub.addActionListener(this);
  bmul.addActionListener(this);
  bdiv.addActionListener(this);
  bcanl.addActionListener(this);
  bequl.addActionListener(this);

  f1.setSize(290, 220);
  f1.pack();
  f1.setVisible(true);
 }

 public static void main(String[] args) {
  new JSanQi();

 }

 public void actionPerformed(ActionEvent event) {
  Object temp = event.getSource();

  try {
   for (int i = 0; i < 10; i++) {
    if (temp == bt[i] && Key == true) {
     t1.setText(t1.getText() + Integer.toString(i));
    }
   }
   if (temp == badd || temp == bsub || temp == bmul || temp == bdiv) {
    if (temp == badd && Key == true) {
     key = 1;
     fnum = Double.parseDouble(t1.getText());
     // t1.setText(t1.getText()+fnum);
    }
    if (temp == bsub && Key == true) {
     key = 2;
     fnum = Double.parseDouble(t1.getText());
    }
    if (temp == bmul && Key == true) {
     key = 3;
     fnum = Double.parseDouble(t1.getText());
    }
    if (temp == bdiv && Key == true) {
     if (Double.parseDouble(t1.getText()) == 0) {
      t1.setText("Wrong action!");
     } else {
      key = 4;
      fnum = Double.parseDouble(t1.getText());
     }
    }
    t1.setText("");
    doc=0;
   }
   if (temp == bequl && Key == true) {
    switch (key) {
    case 1:
     fnum += Double.parseDouble(t1.getText());
     t1.setText(Double.toString(fnum));
     break;
    case 2:
     fnum -= Double.parseDouble(t1.getText());
     t1.setText(Double.toString(fnum));
     break;
    case 3:
     fnum *= Double.parseDouble(t1.getText());
     t1.setText(Double.toString(fnum));
     break;
    case 4:
     fnum /= Double.parseDouble(t1.getText());
     t1.setText(Double.toString(fnum));
     break;
    default:
     break;
    }
    doc=0;
   }
   if (temp == bcanl) {
    t1.setText("");
    Key = true;
    doc=0;

   }
   if (temp == bexit || temp == mt2) {
    System.exit(0);
   }
   if (temp == bzero && Key==true) {
    t1.setText(t1.getText() + "00");
    //doc=0;
   }
   if (temp == mt1) {
    JOptionPane.showMessageDialog(p1, "How Are You!\n"
      + "Architect Is Topwise ^_^");

   }
   
   if (temp == bdoc && Key==true) {
    if (doc == 0) {
     t1.setText(t1.getText() + ".");
     }
    
    if(doc==1) {
     t1.setText("Wrong Action");
     Key = false;
     doc = 0;
    }
    doc = 1;
   }
   if (temp==back && Key==true){
    
   }

  } catch (Exception e) {
   t1.setText("Wrong Action!");
   Key = false;
  }
 }

}

还有点未完善，可以试着自己做好！