java中向JList添加滚动条的问题!急~~~

我的源文件是这样的:有两个文件:Application1.java和Frame1.java其中:Application.java如下:packagejlist_test;... 我的源文件是这样的:有两个文件:Application1.java和Frame1.java
其中:Application.java如下:
package jlist_test;

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

/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2007</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

public class Application1 {
boolean packFrame = false;

//Construct the application
public Application1() {
Frame1 frame = new Frame1();
//Validate frames that have preset sizes
//Pack frames that have useful preferred size info, e.g. from their layout
if (packFrame) {
frame.pack();
}
else {
frame.validate();
}
//Center the window
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
Dimension frameSize = frame.getSize();
if (frameSize.height > screenSize.height) {
frameSize.height = screenSize.height;
}
if (frameSize.width > screenSize.width) {
frameSize.width = screenSize.width;
}
frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);
frame.setVisible(true);
}
//Main method
public static void main(String[] args) {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}
catch(Exception e) {
e.printStackTrace();
}
new Application1();
}
}

Frame1.java如下:

package jlist_test;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;

/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2007</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

public class Frame1 extends JFrame {
JPanel contentPane;
XYLayout xYLayout1 = new XYLayout();
//JList jList1 = new JList();
String[] str = {"Math","English","Physics","Chemic","Biology","Politics"};
JList jList1 = new JList(str);
JScrollPane listScrollPane = new JScrollPane(jList1);
//Construct the frame
public Frame1() {
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
}
//Component initialization
private void jbInit() throws Exception {
contentPane = (JPanel) this.getContentPane();
contentPane.setLayout(xYLayout1);
this.setSize(new Dimension(400, 300));
this.setTitle("Frame Title");
jList1.setVisibleRowCount(4);
contentPane.add(jList1, new XYConstraints(72, 86, 213, 73));
}
//Overridden so we can exit when window is closed
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
System.exit(0);
}
}
}

但是在显示出来的列表框中却找不到滚动条的踪影,请问是哪里出了问题,请高手帮忙解决一下,谢谢!用List可以产生滚动条!
展开
 我来答
百度网友5200952
2007-09-09 · TA获得超过6242个赞
知道小有建树答主
回答量:1034
采纳率:0%
帮助的人:0
展开全部
contentPane.add(jList1, new XYConstraints(72, 86, 213, 73));
这个地方应该添加的是listScrollPane而不是list
推荐律师服务: 若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询

为你推荐:

下载百度知道APP,抢鲜体验
使用百度知道APP,立即抢鲜体验。你的手机镜头里或许有别人想知道的答案。
扫描二维码下载
×

类别

我们会通过消息、邮箱等方式尽快将举报结果通知您。

说明

0/200

提交
取消

辅 助

模 式