效果如下

代码实现

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;public class SimpleCalculator {private JFrame frame;private JTextField numField1;private JTextField numField2;private JTextField resultField;private JButton addButton;private JButton subtractButton;private JButton multiplyButton;private JButton divideButton;public SimpleCalculator() {frame = new JFrame("简易计算器");frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.setLayout(new GridLayout(5, 1));frame.setResizable(false); // Disable maximizingJPanel inputPanel = new JPanel();numField1 = new JTextField(5);numField2 = new JTextField(5);resultField = new JTextField(5);resultField.setEditable(false);inputPanel.add(new JLabel("Number 1:"));inputPanel.add(numField1);inputPanel.add(new JLabel("Number 2:"));inputPanel.add(numField2);inputPanel.add(new JLabel("Result:"));inputPanel.add(resultField);JPanel buttonPanel = new JPanel();addButton = new JButton("+");subtractButton = new JButton("-");multiplyButton = new JButton("*");divideButton = new JButton("/");addButton.addActionListener(new OperationListener("+"));subtractButton.addActionListener(new OperationListener("-"));multiplyButton.addActionListener(new OperationListener("*"));divideButton.addActionListener(new OperationListener("/"));buttonPanel.add(addButton);buttonPanel.add(subtractButton);buttonPanel.add(multiplyButton);buttonPanel.add(divideButton);frame.add(inputPanel);frame.add(buttonPanel);frame.pack();frame.setLocationRelativeTo(null); // Place the frame in the center of the screenframe.setVisible(true);}private class OperationListener implements ActionListener {private String operation;public OperationListener(String operation) {this.operation = operation;}@Overridepublic void actionPerformed(ActionEvent e) {double num1 = Double.parseDouble(numField1.getText());double num2 = Double.parseDouble(numField2.getText());double result = 0;switch (operation) {case "+":result = num1 + num2;break;case "-":result = num1 - num2;break;case "*":result = num1 * num2;break;case "/":if (num2 != 0) {result = num1 / num2;} else {JOptionPane.showMessageDialog(frame, "Cannot divide by zero!");return;}break;}resultField.setText(String.valueOf(result));}}public static void main(String[] args) {SwingUtilities.invokeLater(SimpleCalculator::new);}
}