calculatorframe.java

java计算器

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Calculator
{
    public static void main(String[] args)
    {
         CalculatorFrame frame=new CalculatorFrame();
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.show();
        }
    }
   
class CalculatorFrame extends JFrame
{
    public static final int w=300;
    public static final int h=200;
    public CalculatorFrame()
    {
        setTitle("Calculator made by sxl");
        setSize(w,h);
        Container contentPane=getContentPane();
        CalculatorPanel panel=new CalculatorPanel();
        contentPane.add(panel);
    }
}
   class CalculatorPanel extends JPanel
{
    private JTextField show;
    private JPanel panel;
    private JPanel newpanel;
    private double result;
    private String type;
    private boolean start;
    public CalculatorPanel()
    {
        setLayout(new BorderLayout());
        show=new JTextField("0");
        show.setEditable(false);
        result=0;
        type="=";
        start=true;
        add(show,BorderLayout.NORTH);
        ActionListener number=new NumberAction();
        ActionListener type=new TypeAction();
        ActionListener clear=new ClearAction();
        panel=new JPanel();
        panel.setLayout(new GridLayout(3,6));
        addButton("7",number);
        addButton("8",number);
        addButton("9",number);
        addButton("+",type);
        addButton("-",type);
        addButton("C",clear);
        addButton("4",number);
        addButton("5",number);
        addButton("6",number);
        addButton("*",type);
        addButton("/",type);
        addButton("=",type);
        addButton("1",number);
        addButton("2",number);
        addButton("3",number);
        addButton("0",number);
        addButton(".",number);
        add(panel,BorderLayout.CENTER);
    }
    private void addButton(String label,ActionListener listener)
    {
        JButton button=new JButton(label);
        button.addActionListener(listener);
        panel.add(button);
    }
    private class ClearAction implements ActionListener
    {
        public  void actionPerformed(ActionEvent event)
        {
            result=0;
            show.setText("0");
        }
    }
    private class NumberAction implements ActionListener
    {
        public void actionPerformed(ActionEvent event)
        {
            String input=event.getActionCommand();
            if(start){show.setText("");start=false;};
            show.setText(show.getText()+input);
        }
    }
    private class TypeAction implements ActionListener
    {
        public void actionPerformed(ActionEvent event)
        {
            String newtype=event.getActionCommand();
            if(start)
            {
                if(newtype.equals("-"))
                {
                    show.setText(newtype);
                    start=false;
                }
                else
                    type=newtype;
             }
             else
             {
                calculate(Double.parseDouble(show.getText()));
                newtype=type;
                start=true;
             }
         }
     }
     public void calculate(double x)
     {
         if(type.equals("+")) result+=x;
         else if(type.equals("-")) result-=x;
         else if(type.equals("*")) result*=x;
         else if(type.equals("/")) result/=x;
         else if(type.equals("=")) result=x;
         show.setText(""+result);
     }
}