下面的程式碼就演示了為JTextArea、JList增加滾動條的程式碼：

package com.cownew.Char19; import javax.swing.SwingUtilities; import java.awt.BorderLayout; import javax.swing.DefaultListModel; import javax.swing.JPanel; import javax.swing.JFrame; import javax.swing.JTextArea; import javax.swing.ListModel; import java.awt.Rectangle; import javax.swing.JList; import javax.swing.JScrollPane; public class ScrollPaneTest1 extends JFrame { private JPanel jContentPane = null; private JTextArea jTextArea = null; private JList jList = null; private JScrollPane jScrollPane = null; private JScrollPane jScrollPane1 = null; private JList jList1 = null; private JTextArea jTextArea1 = null; private JTextArea getJTextArea() { if (jTextArea == null) { jTextArea = new JTextArea(); jTextArea.setBounds(new Rectangle(12, 7, 95, 71)); } return jTextArea; } private JList getJList() { if (jList == null) { jList = new JList(); jList.setBounds(new Rectangle(8, 92, 106, 71)); DefaultListModel listModel = new DefaultListModel(); listModel.addElement("22222"); listModel.addElement("33333333"); listModel.addElement("55555555555555"); listModel.addElement("8888888888"); listModel.addElement("88888888"); listModel.addElement("999999999"); jList.setModel(listModel); } return jList; } private JScrollPane getJScrollPane() { if (jScrollPane == null) { jScrollPane = new JScrollPane(); jScrollPane.setBounds(new Rectangle(143, 7, 122, 75)); jScrollPane.setViewportView(getJTextArea1()); } return jScrollPane; } private JScrollPane getJScrollPane1() { if (jScrollPane1 == null) { jScrollPane1 = new JScrollPane(); jScrollPane1.setBounds(new Rectangle(142, 96, 128, 68)); jScrollPane1.setViewportView(getJList1()); } return jScrollPane1; } private JList getJList1() { if (jList1 == null) { jList1 = new JList(); DefaultListModel listModel = new DefaultListModel(); listModel.addElement("22222"); listModel.addElement("33333333"); listModel.addElement("8888888888888888888888888888"); listModel.addElement("8888888888"); listModel.addElement("88888888"); listModel.addElement("999999999"); jList1.setModel(listModel); } return jList1; } private JTextArea getJTextArea1() { if (jTextArea1 == null) { jTextArea1 = new JTextArea(); } return jTextArea1; } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { ScrollPaneTest1 thisClass = new ScrollPaneTest1(); thisClass.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); thisClass.setVisible(true); } }); } public ScrollPaneTest1() { super(); initialize(); } private void initialize() { this.setSize(300, 200); this.setContentPane(getJContentPane()); this.setTitle("JFrame"); } private JPanel getJContentPane() { if (jContentPane == null) { jContentPane = new JPanel(); jContentPane.setLayout(null); jContentPane.add(getJTextArea(), null); jContentPane.add(getJList(), null); jContentPane.add(getJScrollPane(), null); jContentPane.add(getJScrollPane1(), null); } return jContentPane; } } 執行效果圖：  圖 17.9 JScrollPane還能為組合介面增加滾動條： package com.cownew.Char19; import java.awt.Dimension; import java.awt.Rectangle; import javax.swing.JButton; import javax.swing.JCheckBox; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JSlider; import javax.swing.JTextField; import javax.swing.SwingUtilities; public class ScrollPaneTest2 extends JFrame { private JPanel jContentPane = null; private JScrollPane jScrollPane = null; private JPanel jPanel = null; private JButton jButton = null; private JButton jButton1 = null; private JCheckBox jCheckBox = null; private JTextField jTextField = null; private JSlider jSlider = null; private JScrollPane getJScrollPane() { if (jScrollPane == null) { jScrollPane = new JScrollPane(); jScrollPane.setBounds(new Rectangle(28, 17, 142, 114)); jScrollPane.setViewportView(getJPanel()); } return jScrollPane; } private JPanel getJPanel() { if (jPanel == null) { jPanel = new JPanel(); jPanel.setLayout(null); jPanel.add(getJButton(), null); jPanel.add(getJButton1(), null); jPanel.add(getJCheckBox(), null); jPanel.add(getJTextField(), null); jPanel.add(getJSlider(), null); jPanel.setPreferredSize(new Dimension(300,200)); } return jPanel; } private JButton getJButton() { if (jButton == null) { jButton = new JButton(); jButton.setBounds(new Rectangle(6, 10, 74, 28)); } return jButton; } private JButton getJButton1() { if (jButton1 == null) { jButton1 = new JButton(); jButton1.setBounds(new Rectangle(102, 9, 82, 30)); } return jButton1; } private JCheckBox getJCheckBox() { if (jCheckBox == null) { jCheckBox = new JCheckBox(); jCheckBox.setBounds(new Rectangle(17, 56, 93, 21)); jCheckBox.setText("aaaaabbb"); } return jCheckBox; } private JTextField getJTextField() { if (jTextField == null) { jTextField = new JTextField(); jTextField.setBounds(new Rectangle(126, 57, 99, 22)); } return jTextField; } private JSlider getJSlider() { if (jSlider == null) { jSlider = new JSlider(); jSlider.setBounds(new Rectangle(20, 111, 205, 25)); } return jSlider; } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { ScrollPaneTest2 thisClass = new ScrollPaneTest2(); thisClass.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); thisClass.setVisible(true); } }); } public ScrollPaneTest2() { super(); initialize(); } private void initialize() { this.setSize(221, 177); this.setContentPane(getJContentPane()); this.setTitle("JFrame"); } private JPanel getJContentPane() { if (jContentPane == null) { jContentPane = new JPanel();