ACM Interactors冻结

解决方法是，除了使用Java1.5外，还应将字段添加到中

NORTH

GraphicsProgram

修改后的SSCCE：

import acm.program.*;import java.awt.event.*;import javax.swing.*;public class TextFieldExample extends GraphicsProgram {    @Override    public void init() {        nameField = new JTextField(15);        add(new JLabel("Name: "), NORTH);        add(nameField, NORTH);        nameField.addActionListener(this);    }    @Override    public void actionPerformed(ActionEvent e) {        if (e.getSource() == nameField) { println("Hello, " + nameField.getText());        }    }    private JTextField nameField;}