下面是我上面提到的一个小的可编辑代码片段.我同意camickr你不应该使用绝对定位而是使用布局管理器.如果你绝对需要为JTextField提供一个水平滚动条,那么让它工作的一种方法就是让它始终显示,使用允许这个的JScrollPane构造函数.即,

JScrollPane inputPane = new JScrollPane(inputField, JScrollPane.VERTICAL_SCROLLBAR_NEVER,

JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);

例如,

import java.awt.*;

import javax.swing.*;

public class FuSwing1b extends JPanel {

private static final int TA_ROWS = 25;

private static final int TA_COLS = 60;

private JTextField inputField = new JTextField();

private JTextArea talkArea = new JTextArea(TA_ROWS, TA_COLS);

public FuSwing1b() {

talkArea.setEditable(false);

talkArea.setFocusable(false);

talkArea.setBackground(Color.white);

//talkArea.setPreferredSize(new Dimension(TALK_WIDTH, TALK_HEIGHT));

JScrollPane talkPane = new JScrollPane(talkArea, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,

JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

JScrollPane inputPane = new JScrollPane(inputField, JScrollPane.VERTICAL_SCROLLBAR_NEVER,

JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);

int gap = 10;

setLayout(new BorderLayout(gap, gap));

add(talkPane, BorderLayout.CENTER);

add(inputPane, BorderLayout.SOUTH);

setBorder(BorderFactory.createEmptyBorder(gap , gap, gap, gap));

}

private static void createAndShowUI() {

JFrame frame = new JFrame("FuSwing1b");

frame.getContentPane().add(new FuSwing1b());

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.pack();

frame.setLocationRelativeTo(null);

frame.setVisible(true);

}

public static void main(String[] args) {

java.awt.EventQueue.invokeLater(new Runnable() {

public void run() {

createAndShowUI();

}

});

}

}