import java.awt.BorderLayout;
import java.awt.Color;
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.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.TitledBorder;public class Jisuanqi extends JFrame implements ActionListener{private JTextField reasult;private JButton btn1,btn2,btn3,btn4,btn5,btn6,btn7,btn8,btn9,btn0,btnAC,btnAdd,btnSub,btnReasult,btnD,btnAbout,btnCancel;private boolean add,sub,end,s,c;private String str;private double num1,num2;public Jisuanqi(){JPanel p1=new JPanel();JPanel p2=new JPanel();JPanel p3=new JPanel();TitledBorder tb=new TitledBorder("OutPut");tb.setTitleColor(Color.YELLOW);btnAbout=new JButton("Producer");btnCancel=new JButton("Close");btnCancel.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent ee){System.exit(0);}});btnAbout.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent ee){JOptionPane.showMessageDialog(null, "刘道广", "制作人",JOptionPane.INFORMATION_MESSAGE);}});p3.add(btnAbout);p3.add(btnCancel);reasult = new JTextField("0",20);reasult.setEditable(false);reasult.setHorizontalAlignment(JTextField.RIGHT);reasult.setForeground(Color.BLUE);p1.setBorder(tb);p1.add(reasult);btn0=new JButton("0"); btn0.addActionListener(this);btn1=new JButton("1");   btn1.addActionListener(this);btn2=new JButton("2");   btn2.addActionListener(this);btn3=new JButton("3");   btn3.addActionListener(this); btn4=new JButton("4");   btn4.addActionListener(this);btn5=new JButton("5");   btn5.addActionListener(this);btn6=new JButton("6");   btn6.addActionListener(this);btn7=new JButton("7");   btn7.addActionListener(this);btn8=new JButton("8");   btn8.addActionListener(this);btn9=new JButton("9");   btn9.addActionListener(this);btnD=new JButton(".");     btnD.addActionListener(this); btnD.setForeground(Color.GREEN);btnAC=new JButton("AC"); btnAC.addActionListener(this); btnAC.setBackground(Color.RED);btnAdd=new JButton("+"); btnAdd.addActionListener(this); btnAdd.setForeground(Color.CYAN);btnSub=new JButton("-"); btnSub.addActionListener(this); btnSub.setForeground(Color.CYAN);btnReasult=new JButton("="); btnReasult.addActionListener(this); btnReasult.setForeground(Color.RED);p2.add(btn1);p2.add(btn2);p2.add(btn3);p2.add(btn4);p2.add(btn5);p2.add(btn6);p2.add(btn7);p2.add(btn8);p2.add(btn9);p2.add(btn0);p2.add(btnD);p2.add(btnAC);p2.add(btnAdd);p2.add(btnSub);p2.add(btnReasult);p2.setLayout(new GridLayout(5,3));add(p1,BorderLayout.NORTH);add(p2,BorderLayout.CENTER);add(p3,BorderLayout.SOUTH);}public void num(int i){String s=null;s=String.valueOf(i);if(end){reasult.setText("0");end=false;}if((reasult.getText()).equals("0")){reasult.setText(s);}else{str=reasult.getText()+s;reasult.setText(str);}}public void actionPerformed(ActionEvent e){if(e.getSource()==btn1) num(1);else if(e.getSource()==btn2) num(2);else if(e.getSource()==btn3) num(3);else if(e.getSource()==btn4) num(4);else if(e.getSource()==btn5) num(5);else if(e.getSource()==btn6) num(6);else if(e.getSource()==btn7) num(7);else if(e.getSource()==btn8) num(8);else if(e.getSource()==btn9) num(9);else if(e.getSource()==btn0) num(0);else if(e.getSource()==btnAdd){sign(1);btnD.setEnabled(true);}else if(e.getSource()==btnSub){sign(2);btnD.setEnabled(true);}else if(e.getSource()==btnAC){btnD.setEnabled(true);reasult.setText("0");}else if(e.getSource()==btnD){str=reasult.getText();str+='.';reasult.setText(str);btnD.setEnabled(false);}else if(e.getSource()==btnReasult){btnD.setEnabled(true);num2=Double.parseDouble(reasult.getText());if(add){num1=num1+num2;}else if(sub){num1=num1-num2;}reasult.setText(String.valueOf(num1));end=true;}}public void sign(int s){if(s==1){add=true;sub=false;}else if(s==2){add=false;sub=true;}num1=Double.parseDouble(reasult.getText());end=true;}public static void main(String[] args){Jisuanqi j=new Jisuanqi();j.setTitle("+/-简易计算器");j.setLocation(500, 280);j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);j.setResizable(false);j.pack();j.setVisible(true);}
}