Java Swing卡布局更改顯示的面板？

Question

所以我有一個面板這個jFrame。 在該面板內部還有兩個面板，佈局設置爲卡片。 這兩個面板中的一個有一個按鈕。 如何更改當按下該按鈕時顯示的面板？

Answer 1

試試這個代碼片段，希望評論可以幫助你理解序列。

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

/* Here we are first declaring our class that will act as the 
* base for other panels or in other terms the base for CardLayout. 
*/ 

public class CardLayoutTest 
{ 
    private static final String CARD_JBUTTON = "Card JButton"; 
    private static final String CARD_JTEXTFIELD = "Card JTextField";  
    private static final String CARD_JRADIOBUTTON = "Card JRadioButton"; 

    private static void createAndShowGUI() 
    { 
     JFrame frame = new JFrame("Card Layout Test"); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.setLocationRelativeTo(null); 

     // This JPanel is the base for CardLayout for other JPanels. 
     final JPanel contentPane = new JPanel(); 
     contentPane.setLayout(new CardLayout(20, 20)); 

     /* Here we be making objects of the Window Series classes 
     * so that, each one of them can be added to the JPanel 
     * having CardLayout. 
     */ 
     Window1 win1 = new Window1(); 
     contentPane.add(win1, CARD_JBUTTON); 
     Window2 win2 = new Window2(); 
     contentPane.add(win2, CARD_JTEXTFIELD); 
     Window3 win3 = new Window3(); 
     contentPane.add(win3, CARD_JRADIOBUTTON); 

     /* We need two JButtons to go to the next Card 
     * or come back to the previous Card, as and when 
     * desired by the User. 
     */ 
     JPanel buttonPanel = new JPanel(); 
     final JButton previousButton = new JButton("PREVIOUS"); 
     previousButton.setBackground(Color.BLACK); 
     previousButton.setForeground(Color.WHITE); 
     final JButton nextButton = new JButton("NEXT"); 
     nextButton.setBackground(Color.RED); 
     nextButton.setForeground(Color.WHITE); 
     buttonPanel.add(previousButton); 
     buttonPanel.add(nextButton); 

     /* Adding the ActionListeners to the JButton, 
     * so that the user can see the next Card or 
     * come back to the previous Card, as desired. 
     */ 
     previousButton.addActionListener(new ActionListener() 
     { 
      public void actionPerformed(ActionEvent ae) 
      { 
       CardLayout cardLayout = (CardLayout) contentPane.getLayout(); 
       cardLayout.previous(contentPane); 
      } 
     }); 
     nextButton.addActionListener(new ActionListener() 
     { 
      public void actionPerformed(ActionEvent ae) 
      { 
       CardLayout cardLayout = (CardLayout) contentPane.getLayout(); 
       cardLayout.next(contentPane); 
      } 
     }); 

     // Adding the contentPane (JPanel) and buttonPanel to JFrame. 
     frame.add(contentPane, BorderLayout.CENTER); 
     frame.add(buttonPanel, BorderLayout.PAGE_END); 

     frame.pack(); 
     frame.setVisible(true); 
    } 

    public static void main(String... args) 
    { 
     SwingUtilities.invokeLater(new Runnable() 
     { 
      public void run() 
      { 
       createAndShowGUI(); 
      } 
     }); 
    } 
} 

class Window1 extends JPanel 
{ 
    /* 
    * Here this is our first Card of CardLayout, which will 
    * be added to the contentPane object of JPanel, which 
    * has the LayoutManager set to CardLayout. 
    * This card consists of Two JButtons. 
    */ 
    private ActionListener action; 

    public Window1() 
    { 
     init(); 
    } 

    private void init() 
    { 
     final JButton clickButton = new JButton("CLICK ME"); 
     final JButton dontClickButton = new JButton("DON\'T CLICK ME");  

     action = new ActionListener() 
     { 
      public void actionPerformed(ActionEvent ae) 
      { 
       if (ae.getSource() == clickButton) 
       { 
        JOptionPane.showMessageDialog(null, "Hello there dude!" 
               , "Right Button", JOptionPane.INFORMATION_MESSAGE); 
       } 
       else if (ae.getSource() == dontClickButton) 
       { 
        JOptionPane.showMessageDialog(null, "I told you not to click me!" 
                 , "Wrong Button", JOptionPane.PLAIN_MESSAGE); 
       } 
      } 
     }; 

     clickButton.addActionListener(action); 
     dontClickButton.addActionListener(action); 

     add(clickButton); 
     add(dontClickButton); 
    } 
} 

class Window2 extends JPanel implements ActionListener 
{ 
    /* 
    * Here this is our second Card of CardLayout, which will 
    * be added to the contentPane object of JPanel, which 
    * has the LayoutManager set to CardLayout. 
    * This card consists of a JLabel and a JTextField 
    * with GridLayout. 
    */ 

    private JTextField textField; 

    public Window2() 
    { 
     init(); 
    } 

    private void init() 
    { 
     setLayout(new GridLayout(1, 2)); 
     JLabel userLabel = new JLabel("Your Name : "); 
     textField = new JTextField(); 
     textField.addActionListener(this); 

     add(userLabel); 
     add(textField); 
    } 

    public void actionPerformed(ActionEvent e) 
    {    
     if (textField.getDocument().getLength() > 0) 
      JOptionPane.showMessageDialog(null, "Your Name is : " + textField.getText() 
                      , "User\'s Name : ", JOptionPane.QUESTION_MESSAGE); 
    } 
} 

class Window3 extends JPanel 
{ 
    /* 
    * Here this is our third Card of CardLayout, which will 
    * be added to the contentPane object of JPanel, which 
    * has the LayoutManager set to CardLayout. 
    * This card consists of Two JLabels and two JCheckBox 
    * with GridLayout. 
    */ 
    private ActionListener state; 

    public Window3() 
    { 
     init(); 
    } 

    public void init() 
    { 
     setLayout(new GridLayout(2, 2)); 
     JLabel maleLabel = new JLabel("MALE", JLabel.CENTER); 
     final JCheckBox maleBox = new JCheckBox(); 
     JLabel femaleLabel = new JLabel("FEMALE", JLabel.CENTER); 
     final JCheckBox femaleBox = new JCheckBox(); 

     state = new ActionListener() 
     { 
      public void actionPerformed(ActionEvent ae) 
      { 
       if (maleBox == (JCheckBox) ae.getSource()) 
       { 
        femaleBox.setSelected(false); 
        JOptionPane.showMessageDialog(null, "Congrats you are a Male" 
               , "Gender : ", JOptionPane.INFORMATION_MESSAGE);        
       } 
       else if (femaleBox == (JCheckBox) ae.getSource()) 
       { 
        maleBox.setSelected(false); 
        JOptionPane.showMessageDialog(null, "Congrats you are a Female" 
              , "Gender : ", JOptionPane.INFORMATION_MESSAGE);       
       } 
      } 
     }; 

     maleBox.addActionListener(state); 
     femaleBox.addActionListener(state); 
     add(maleLabel); 
     add(maleBox); 
     add(femaleLabel); 
     add(femaleBox); 
    } 
}