如何从另一个单独的类更改java Cardlayout
请问我一直在尝试从另一个类（JPanel）切换CardLayout，这是CardLayout上的卡之一，我已经搜索并对此进行了很长时间的研究，但没有发现任何有用的信息。
我有一个CardLayout和两个单独的JPanels，我添加到CardLayout，现在我希望能够在单独的JPanel或单独的类上执行活动后切换卡，那么如何从另一个类切换CardLayout？ 我的代码如下。
package myApp; import java.awt.CardLayout; public class TestmyCard extends javax.swing.JFrame { /** * Creates new form TestmyCard */ public TestmyCard() { initComponents(); jPanel1.add(new FirstCard(),"card3"); jPanel1.add(new SecondCard(),"card4"); } public void chgCard(String nwCard){ CardLayout cl = (CardLayout)(jPanel1.getLayout()); cl.show(jPanel1,nwCard); } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // private void initComponents() { jPanel1 = new javax.swing.JPanel(); jPanel2 = new javax.swing.JPanel(); jLabel1 = new javax.swing.JLabel(); jPanel3 = new javax.swing.JPanel(); jButton1 = new javax.swing.JButton(); jButton2 = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jPanel1.setName("Cards"); jPanel1.setLayout(new java.awt.CardLayout()); jPanel2.setName("card2"); jLabel1.setText("second panel"); javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2); jPanel2.setLayout(jPanel2Layout); jPanel2Layout.setHorizontalGroup( jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel2Layout.createSequentialGroup() .addGap(119, 119, 119) .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 117, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(203, Short.MAX_VALUE)) ); jPanel2Layout.setVerticalGroup( jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel2Layout.createSequentialGroup() .addGap(140, 140, 140) .addComponent(jLabel1) .addContainerGap(92, Short.MAX_VALUE)) ); jPanel1.add(jPanel2, "card2"); jPanel3.setBackground(new java.awt.Color(153, 255, 153)); jButton1.setLabel("First Btn"); jButton1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton1ActionPerformed(evt); } }); jButton2.setLabel("Second Btn"); jButton2.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton2ActionPerformed(evt); } }); javax.swing.GroupLayout jPanel3Layout = new javax.swing.GroupLayout(jPanel3); jPanel3.setLayout(jPanel3Layout); jPanel3Layout.setHorizontalGroup( jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel3Layout.createSequentialGroup() .addContainerGap() .addComponent(jButton1) .addGap(18, 18, 18) .addComponent(jButton2) .addContainerGap(181, Short.MAX_VALUE)) ); jPanel3Layout.setVerticalGroup( jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel3Layout.createSequentialGroup() .addContainerGap(27, Short.MAX_VALUE) .addGroup(jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jButton1) .addComponent(jButton2)) .addGap(20, 20, 20)) ); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, 439, javax.swing.GroupLayout.PREFERRED_SIZE) .addGap(0, 0, Short.MAX_VALUE)) .addGroup(layout.createSequentialGroup() .addGap(37, 37, 37) .addComponent(jPanel3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap()) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, 246, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 25, Short.MAX_VALUE) .addComponent(jPanel3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap()) ); pack(); }// private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: CardLayout cl = (CardLayout)(jPanel1.getLayout()); cl.show(jPanel1,"card3"); //cl.next(jPanel1) ; } private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: CardLayout cl = (CardLayout)(jPanel1.getLayout()); cl.show(jPanel1,"card4"); } /** * @param args the command line arguments */ public static void main(String args[]) { /* * Set the Nimbus look and feel */ // /* * If Nimbus (introduced in Java SE 6) is not available, stay with the * default look and feel. For details see * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(TestmyCard.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(TestmyCard.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(TestmyCard.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(TestmyCard.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } // /* * Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new TestmyCard().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JButton jButton2; private javax.swing.JLabel jLabel1; private javax.swing.JPanel jPanel1; private javax.swing.JPanel jPanel2; private javax.swing.JPanel jPanel3; // End of variables declaration } FirstCard（单独的jpanel）
package myApp; public class FirstCard extends javax.swing.JPanel { /** * Creates new form FirstCard */ public FirstCard() { initComponents(); } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // private void initComponents() { jLabel1 = new javax.swing.JLabel(); guName = new javax.swing.JTextField(); guAddrs = new javax.swing.JTextField(); jLabel14 = new javax.swing.JLabel(); jLabel15 = new javax.swing.JLabel(); guOccu = new javax.swing.JTextField(); jLabel16 = new javax.swing.JLabel(); guPhone = new javax.swing.JTextField(); jLabel1.setText("Guarantee Name :"); jLabel14.setText("Address :"); jLabel15.setText("Occupation :"); jLabel16.setText("Phone :"); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this); this.setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING) .addGroup(layout.createSequentialGroup() .addComponent(jLabel14) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(guAddrs, javax.swing.GroupLayout.PREFERRED_SIZE, 158, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(jLabel16) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(guPhone, javax.swing.GroupLayout.PREFERRED_SIZE, 158, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(jLabel15) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(guOccu, javax.swing.GroupLayout.PREFERRED_SIZE, 158, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(jLabel1) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(guName, javax.swing.GroupLayout.PREFERRED_SIZE, 158, javax.swing.GroupLayout.PREFERRED_SIZE))) .addContainerGap(228, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(43, 43, 43) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel1) .addComponent(guName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel15) .addComponent(guOccu, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGap(30, 30, 30) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel14) .addComponent(guAddrs, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel16) .addComponent(guPhone, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addContainerGap(135, Short.MAX_VALUE)) ); }// // Variables declaration - do not modify private javax.swing.JTextField guAddrs; private javax.swing.JTextField guName; private javax.swing.JTextField guOccu; private javax.swing.JTextField guPhone; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel14; private javax.swing.JLabel jLabel15; private javax.swing.JLabel jLabel16; // End of variables declaration }
SecondCard（单独的jpanel）
package myApp; public class SecondCard extends javax.swing.JPanel { /** * Creates new form SecondCard */ public SecondCard() { initComponents(); } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // private void initComponents() { jLabel1 = new javax.swing.JLabel(); jButton1 = new javax.swing.JButton(); jLabel1.setText("this is the second card"); jButton1.setText("SwitchCard"); jButton1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton1ActionPerformed(evt); } }); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this); this.setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(120, 120, 120) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jButton1) .addComponent(jLabel1)) .addContainerGap(173, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(62, 62, 62) .addComponent(jLabel1) .addGap(18, 18, 18) .addComponent(jButton1) .addContainerGap(183, Short.MAX_VALUE)) ); }// private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: TestmyCard nc = new TestmyCard(); nc.chgCard("Card2"); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JLabel jLabel1; // End of variables declaration }
在您提供的代码中，您从未将FirstCard和SecondCard添加到布局设置为CardLayout的JPanel中。 既然你写的是这样的：
jPanel1.add(jPanel2, "card2");
这里jPanel2是JPanel一个实例，因为你已经在你的TestmyClass类中初始化了它，如下所示：
jPanel2 = new javax.swing.JPanel();
相反，我想你应该写的是：
jPanel2 = new SecondCard(passPanelWithCardLayoutAsArgument); // So that you can manoeuvre around b/w other JPanels
以下是一个小工作示例供您使用：
import java.awt.*; import java.awt.event.*; import javax.swing.*; public class CardLayoutExample { private JPanel contentPane; private MyPanel panel1; private MyPanel panel2; private MyPanel panel3; private void displayGUI() { JFrame frame = new JFrame("Card Layout Example"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JPanel contentPane = new JPanel(); contentPane.setBorder( BorderFactory.createEmptyBorder(5, 5, 5, 5)); contentPane.setLayout(new CardLayout()); panel1 = new MyPanel(contentPane , Color.RED.darker().darker()); panel2 = new MyPanel(contentPane , Color.GREEN.darker().darker()); panel3 = new MyPanel(contentPane , Color.DARK_GRAY); contentPane.add(panel1, "Panel 1"); contentPane.add(panel2, "Panel 2"); contentPane.add(panel3, "Panel 3"); frame.setContentPane(contentPane); frame.pack(); frame.setLocationByPlatform(true); frame.setVisible(true); } public static void main(String... args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new CardLayoutExample().displayGUI(); } }); } } class MyPanel extends JPanel { private JButton jcomp1; private JPanel contentPane; private Color backgroundColour; public MyPanel(JPanel panel, Color c) { contentPane = panel; backgroundColour = c; setOpaque(true); setBackground(backgroundColour); //construct components jcomp1 = new JButton ("Show New Panel"); jcomp1.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { CardLayout cardLayout = (CardLayout) contentPane.getLayout(); cardLayout.next(contentPane); } }); add(jcomp1); } @Override public Dimension getPreferredSize() { return (new Dimension(500, 500)); } }
最新编辑： * 使用您的组件并尝试将其放入CardLayout，使用以下代码：*
import java.awt.*; import java.awt.event.*; import javax.swing.*; public class CardLayoutExample { private JPanel contentPane; private FirstCard panel1; private SecondCard panel2; private void displayGUI() { JFrame frame = new JFrame("Card Layout Example"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JPanel contentPane = new JPanel(); contentPane.setBorder( BorderFactory.createEmptyBorder(5, 5, 5, 5)); contentPane.setLayout(new CardLayout()); panel1 = new FirstCard(contentPane); panel2 = new SecondCard(contentPane); contentPane.add(panel1, "Panel 1"); contentPane.add(panel2, "Panel 2"); frame.setContentPane(contentPane); frame.pack(); frame.setLocationByPlatform(true); frame.setVisible(true); } public static void main(String... args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new CardLayoutExample().displayGUI(); } }); } } class FirstCard extends javax.swing.JPanel { private javax.swing.JTextField addField; private javax.swing.JTextField nameField; private javax.swing.JTextField occField; private javax.swing.JTextField phoneField; private javax.swing.JLabel nameLabel; private javax.swing.JLabel addLabel; private javax.swing.JLabel occLabel; private javax.swing.JLabel phoneLabel; private JPanel centerPanel; private JPanel contentPane; private JButton nextButton; public FirstCard(JPanel cp) { this.contentPane = cp; initComponents(); } private void initComponents() { setOpaque(true); setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); setBackground(Color.RED); setLayout(new BorderLayout(5, 5)); nameLabel = new javax.swing.JLabel("Guarantee Name : "); nameField = new javax.swing.JTextField(); addLabel = new javax.swing.JLabel("Address : "); addField = new javax.swing.JTextField(); occLabel = new javax.swing.JLabel("Occupation : "); occField = new javax.swing.JTextField(); phoneLabel = new javax.swing.JLabel("Phone : "); phoneField = new javax.swing.JTextField(); centerPanel = new JPanel(); nextButton = new JButton("Next"); nextButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent ae) { nextButtonAction(ae); } }); centerPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); centerPanel.setOpaque(true); centerPanel.setBackground(Color.WHITE); centerPanel.setLayout(new GridLayout(0, 2, 5, 5)); centerPanel.add(nameLabel); centerPanel.add(nameField); centerPanel.add(addLabel); centerPanel.add(addField); centerPanel.add(occLabel); centerPanel.add(occField); centerPanel.add(phoneLabel); centerPanel.add(phoneField); add(centerPanel, BorderLayout.CENTER); add(nextButton, BorderLayout.PAGE_END); } private void nextButtonAction(ActionEvent ae) { CardLayout layout = (CardLayout)contentPane.getLayout(); layout.next(contentPane); } } class SecondCard extends javax.swing.JPanel { private javax.swing.JButton nextButton; private javax.swing.JLabel textLabel; private JPanel contentPane; public SecondCard(JPanel cp) { contentPane = cp; initComponents(); } private void initComponents() { setOpaque(true); setBackground(Color.GREEN.darker().darker()); setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); textLabel = new JLabel("this is the second card", JLabel.CENTER); textLabel.setForeground(Color.WHITE); nextButton = new javax.swing.JButton(); nextButton.setText("SwitchCard"); nextButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent evt) { jButton1ActionPerformed(evt); } }); add(textLabel); add(nextButton); } private void jButton1ActionPerformed(ActionEvent evt) { CardLayout layout = (CardLayout) contentPane.getLayout(); layout.show(contentPane, "Panel 1"); } }
清除字段的方法
private void clearFields() { Component components[] = centerPanel.getComponents(); for (Component comp : components) { if (comp instanceof JTextField) { JTextField tfield = (JTextField) comp; tfield.setText(""); } else if (comp instanceof JComboBox) { JComboBox cbox = (JComboBox) comp; cbox.setSelectedIndex(0); } else if (comp instanceof JRadioButton) { JRadioButton rbut = (JRadioButton) comp; rbut.setSelected(false); } } }
你将在Button的actionPerformed()方法中调用它，它将带你到下一张Card。