javaswing界面设计计算器

下面是一个简单的Java Swing界面设计计算器的示例代码：

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

public class Calculator extends JFrame implements ActionListener {
    private static final long serialVersionUID = 1L;
    private final int WIDTH = 300;
    private final int HEIGHT = 400;

    private JTextField textField;

    private JButton button0;
    private JButton button1;
    private JButton button2;
    private JButton button3;
    private JButton button4;
    private JButton button5;
    private JButton button6;
    private JButton button7;
    private JButton button8;
    private JButton button9;

    private JButton buttonAdd;
    private JButton buttonSubtract;
    private JButton buttonMultiply;
    private JButton buttonDivide;
    private JButton buttonClear;
    private JButton buttonEqual;

    private double firstNumber;
    private double secondNumber;
    private double result;
    private String operator;

    public Calculator() {
        setTitle("Calculator");
        setSize(WIDTH, HEIGHT);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setResizable(false);

        textField = new JTextField(20);
        textField.setEditable(false);

        button0 = new JButton("0");
        button1 = new JButton("1");
        button2 = new JButton("2");
        button3 = new JButton("3");
        button4 = new JButton("4");
        button5 = new JButton("5");
        button6 = new JButton("6");
        button7 = new JButton("7");
        button8 = new JButton("8");
        button9 = new JButton("9");

        buttonAdd = new JButton("+");
        buttonSubtract = new JButton("-");
        buttonMultiply = new JButton("*");
        buttonDivide = new JButton("/");
        buttonClear = new JButton("C");
        buttonEqual = new JButton("=");

        JPanel panel1 = new JPanel(new GridLayout(1, 1));
        panel1.add(textField);

        JPanel panel2 = new JPanel(new GridLayout(4, 4));
        panel2.add(button7);
        panel2.add(button8);
        panel2.add(button9);
        panel2.add(buttonDivide);
        panel2.add(button4);
        panel2.add(button5);
        panel2.add(button6);
        panel2.add(buttonMultiply);
        panel2.add(button1);
        panel2.add(button2);
        panel2.add(button3);
        panel2.add(buttonSubtract);
        panel2.add(button0);
        panel2.add(buttonClear);
        panel2.add(buttonEqual);
        panel2.add(buttonAdd);

        button0.addActionListener(this);
        button1.addActionListener(this);
        button2.addActionListener(this);
        button3.addActionListener(this);
        button4.addActionListener(this);
        button5.addActionListener(this);
        button6.addActionListener(this);
        button7.addActionListener(this);
        button8.addActionListener(this);
        button9.addActionListener(this);

        buttonAdd.addActionListener(this);
        buttonSubtract.addActionListener(this);
        buttonMultiply.addActionListener(this);
        buttonDivide.addActionListener(this);
        buttonClear.addActionListener(this);
        buttonEqual.addActionListener(this);

        setLayout(new BorderLayout());
        add(panel1, BorderLayout.NORTH);
        add(panel2, BorderLayout.CENTER);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == button0) {
            textField.setText(textField.getText() + "0");
        } else if (e.getSource() == button1) {
            textField.setText(textField.getText() + "1");
        } else if (e.getSource() == button2) {
            textField.setText(textField.getText() + "2");
        } else if (e.getSource() == button3) {
            textField.setText(textField.getText() + "3");
        } else if (e.getSource() == button4) {
            textField.setText(textField.getText() + "4");
        } else if (e.getSource() == button5) {
            textField.setText(textField.getText() + "5");
        } else if (e.getSource() == button6) {
            textField.setText(textField.getText() + "6");
        } else if (e.getSource() == button7) {
            textField.setText(textField.getText() + "7");
        } else if (e.getSource() == button8) {
            textField.setText(textField.getText() + "8");
        } else if (e.getSource() == button9) {
            textField.setText(textField.getText() + "9");
        } else if (e.getSource() == buttonAdd) {
            firstNumber = Double.parseDouble(textField.getText());
            operator = "+";
            textField.setText("");
        } else if (e.getSource() == buttonSubtract) {
            firstNumber = Double.parseDouble(textField.getText());
            operator = "-";
            textField.setText("");
        } else if (e.getSource() == buttonMultiply) {
            firstNumber = Double.parseDouble(textField.getText());
            operator = "*";
            textField.setText("");
        } else if (e.getSource() == buttonDivide) {
            firstNumber = Double.parseDouble(textField.getText());
            operator = "/";
            textField.setText("");
        } else if (e.getSource() == buttonClear) {
            textField.setText("");
        } else if (e.getSource() == buttonEqual) {
            secondNumber = Double.parseDouble(textField.getText());
            if (operator.equals("+")) {
                result = firstNumber + secondNumber;
            } else if (operator.equals("-")) {
                result = firstNumber - secondNumber;
            } else if (operator.equals("*")) {
                result = firstNumber * secondNumber;
            } else if (operator.equals("/")) {
                result = firstNumber / secondNumber;
            }
            textField.setText(Double.toString(result));
        }
    }

    public static void main(String[] args) {
        Calculator calculator = new Calculator();
        calculator.setVisible(true);
    }
}

这个示例代码创建了一个简单的计算器界面，用户可以通过按下数字键和运算符键进行计算。该计算器支持加、减、乘、除四种基本运算，并且提供清除和等于两个特殊功能。

在这个示例代码中，计算器界面被分成了两个JPanel面板。第一个JPanel包含一个JTextField，用于显示用户输入和计算结果。第二个JPanel包含数字键和运算符键。在JFrame的BorderLayout布局中，第一个JPanel被放置在北部，第二个JPanel被放置在中心。

在这个示例代码中，所有数字键和运算符键都被分别创建为JButton对象，并且被添加到第二个JPanel中。每个JButton都有一个ActionListener，当用户单击它时，它将调用actionPerformed()方法。在actionPerformed()方法中，根据单击的按钮类型，执行相应的操作（添加数字、选择运算符、清除文本框、计算结果等）。

最后，该示例代码创建了一个Calculator对象，并将其设置为可见。这将启动计算器应用程序，并显示计算器界面。