以下是一个使用 Java 的 Swing 库来实现上述功能的示例代码: ```java import javax.swing.JFrame; import javax.swing.JTextField; import javax.swing.JLabel; import javax.swing.JButton; import javax.swing.JOptionPane; import java.awt.event.ActionListener; import java.awt.event.ActionEvent; public class SquareCalculator extends JFrame implements ActionListener { private JTextField inputTextField; private JTextField outputTextField; public SquareCalculator() { setTitle("计算平方"); JLabel inputLabel = new JLabel("输入数字:"); inputTextField = new JTextField(10); JLabel outputLabel = new JLabel("结果:"); outputTextField = new JTextField(10); outputTextField.setEditable(false); JButton calculateButton = new JButton("计算"); calculateButton.addActionListener(this); add(inputLabel); add(inputTextField); add(outputLabel); add(outputTextField); add(calculateButton); setLayout(null); inputLabel.setBounds(50, 50, 80, 25); inputTextField.setBounds(130, 50, 100, 25); outputLabel.setBounds(50, 100, 80, 25); outputTextField.setBounds(130, 100, 100, 25); calculateButton.setBounds(100, 150, 80, 25); setSize(300, 250); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); } @Override public void actionPerformed(ActionEvent e) { String input = inputTextField.getText(); try { int num = Integer.parseInt(input); int square = num * num; outputTextField.setText(String.valueOf(square)); } catch (NumberFormatException ex) { outputTextField.setText("请输入数字"); } } public static void main(String[] args) { new SquareCalculator(); } } ``` [2024-09-25 18:22:24 | AI写代码神器 | 479点数解答]