How to link a button a card layout to another card (JPanel)

[bernard kissi]

I want  to link button on a card(JPanel) in a cardLayout to another card(JPanel) in the same Layout.
components
i Have 2 Panel class  = 1. welcome.class , snacks.class
and 1 jframe class =  kiosk.class

Already i can switch through view using the flowLayout but i want to link a button from one card to the other
Purpose
What i want to achieve is how to use a button on welcome panel and navigate to the snack panel within a cardLayout



This is what i tried
KIOSK CLASS(JFRAME CONTAINING VIEWS)

package views;

import java.awt.CardLayout;
import java.awt.Container;

/**
 *
 * @author user
 */
public class kiosk extends javax.swing.JFrame {

    /**
     * Creates new form kiosk
     */
    public kiosk() {
        initComponents();
        
    }

    
      public void switchPanel(Container container, String panelName) {
        CardLayout card = (CardLayout) container.getLayout();
        card.show(container, panelName);
    }
    /**
     * 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")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        jButton4 = new javax.swing.JButton();
        drinks = new javax.swing.JButton();
        snacks = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        panelCard = new javax.swing.JPanel();
        welcome1 = new views.Welcome();
        drinks1 = new views.drinks();
        snacks1 = new views.snacks();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jPanel1.setBackground(new java.awt.Color(51, 51, 51));

        jButton4.setFont(new java.awt.Font("DIN Alternate", 0, 12)); // NOI18N
        jButton4.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Entypo_2302(0)_24.png"))); // NOI18N
        jButton4.setText("HOME  ");
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });
        jPanel1.add(jButton4);

        drinks.setFont(new java.awt.Font("DIN Alternate", 0, 12)); // NOI18N
        drinks.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Entypo_23ea(1)_24.png"))); // NOI18N
        drinks.setText("SELECT DRINK  ");
        drinks.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                drinksActionPerformed(evt);
            }
        });
        jPanel1.add(drinks);

        snacks.setFont(new java.awt.Font("DIN Alternate", 0, 12)); // NOI18N
        snacks.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Entypo_23e9(2)_24.png"))); // NOI18N
        snacks.setText("SELECT SNACK  ");
        snacks.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                snacksActionPerformed(evt);
            }
        });
        jPanel1.add(snacks);

        jButton3.setFont(new java.awt.Font("DIN Alternate", 0, 12)); // NOI18N
        jButton3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Entypo_e715(3)_24.png"))); // NOI18N
        jButton3.setText("EXIT  ");
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });
        jPanel1.add(jButton3);

        getContentPane().add(jPanel1, java.awt.BorderLayout.SOUTH);

        panelCard.setLayout(new java.awt.CardLayout());
        panelCard.add(welcome1, "Welcome");
        panelCard.add(drinks1, "drinks");
        panelCard.add(snacks1, "snacks");

        getContentPane().add(panelCard, java.awt.BorderLayout.PAGE_START);

        pack();
    }// </editor-fold>                        

    private void drinksActionPerformed(java.awt.event.ActionEvent evt) {                                       
        CardLayout showPanel =  (CardLayout) panelCard.getLayout();
        showPanel.show(panelCard, "drinks");
    }                                      

    private void snacksActionPerformed(java.awt.event.ActionEvent evt) {                                       
        CardLayout showPanel =  (CardLayout) panelCard.getLayout();
        showPanel.show(panelCard, "snacks");
    }                                      

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        System.exit(0);
    }                                        

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        CardLayout showPanel =  (CardLayout) panelCard.getLayout();
        showPanel.show(panelCard, "Welcome");
    }                                        

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
       
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Windows".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(kiosk.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(kiosk.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(kiosk.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(kiosk.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                //for(int i =0; i < 2; i++){
                    new kiosk().setVisible(true);
                //}
                
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton drinks;
    private views.drinks drinks1;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JPanel panelCard;
    private javax.swing.JButton snacks;
    private views.snacks snacks1;
    private views.Welcome welcome1;
    // End of variables declaration                   

    
}

WELCOME.CLASS(JPANEL FORM)

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package views;

import javax.swing.JPanel;



/**
 *
 * @author user
 */
public class Welcome extends JPanel {

   private JPanel panelCard;
    
    
    
    /**
     * Creates new form Welcome
     */
    public Welcome() {
        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")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        jLabel1 = new javax.swing.JLabel();
        jLabel5 = new javax.swing.JLabel();
        jPanel2 = new javax.swing.JPanel();
        jPanel4 = new javax.swing.JPanel();
        jButton2 = new javax.swing.JButton();
        jLabel3 = new javax.swing.JLabel();
        jPanel6 = new javax.swing.JPanel();
        jButton3 = new javax.swing.JButton();
        jLabel4 = new javax.swing.JLabel();
        jPanel5 = new javax.swing.JPanel();
        jButton1 = new javax.swing.JButton();
        jLabel2 = new javax.swing.JLabel();

        setPreferredSize(new java.awt.Dimension(933, 523));

        jPanel1.setBackground(new java.awt.Color(204, 102, 0));

        jLabel1.setIcon(new javax.swing.ImageIcon(getClass().getResource("/views/SNP_GLO_HDR_Logo_202x151.png"))); // NOI18N
        jLabel1.setText("jLabel1");

        jLabel5.setBackground(new java.awt.Color(255, 255, 255));
        jLabel5.setFont(new java.awt.Font("Dialog", 0, 13)); // NOI18N
        jLabel5.setForeground(new java.awt.Color(255, 255, 255));
        jLabel5.setIcon(new javax.swing.ImageIcon(getClass().getResource("/views/logistics-delivery-truck-in-movement-2.png"))); // NOI18N
        jLabel5.setText("CALL FOR DELIVERY  : 1800-FOOD");

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(41, 41, 41)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 208, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 370, Short.MAX_VALUE)
                .addComponent(jLabel5)
                .addGap(48, 48, 48))
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addContainerGap())
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGap(28, 28, 28)
                .addComponent(jLabel5)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        jPanel2.setBackground(new java.awt.Color(255, 255, 255));
        jPanel2.setPreferredSize(new java.awt.Dimension(933, 353));

        jButton2.setFont(new java.awt.Font("DIN Alternate", 0, 18)); // NOI18N
        jButton2.setIcon(new javax.swing.ImageIcon(getClass().getResource("/views/coffee-cup-2.png"))); // NOI18N
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton2ActionPerformed(evt);
            }
        });

        jLabel3.setFont(new java.awt.Font("DIN Alternate", 0, 20)); // NOI18N
        jLabel3.setText("                   DRINKS");

        javax.swing.GroupLayout jPanel4Layout = new javax.swing.GroupLayout(jPanel4);
        jPanel4.setLayout(jPanel4Layout);
        jPanel4Layout.setHorizontalGroup(
            jPanel4Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jLabel3, javax.swing.GroupLayout.DEFAULT_SIZE, 267, Short.MAX_VALUE)
        );
        jPanel4Layout.setVerticalGroup(
            jPanel4Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel4Layout.createSequentialGroup()
                .addComponent(jButton2, javax.swing.GroupLayout.PREFERRED_SIZE, 203, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(0, 0, 0)
                .addComponent(jLabel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        jButton3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/views/sandwich.png"))); // NOI18N
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });

        jLabel4.setFont(new java.awt.Font("DIN Alternate", 0, 20)); // NOI18N
        jLabel4.setText("              SANDWICH");

        javax.swing.GroupLayout jPanel6Layout = new javax.swing.GroupLayout(jPanel6);
        jPanel6.setLayout(jPanel6Layout);
        jPanel6Layout.setHorizontalGroup(
            jPanel6Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jLabel4, javax.swing.GroupLayout.DEFAULT_SIZE, 256, Short.MAX_VALUE)
        );
        jPanel6Layout.setVerticalGroup(
            jPanel6Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel6Layout.createSequentialGroup()
                .addComponent(jButton3, javax.swing.GroupLayout.PREFERRED_SIZE, 203, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(0, 0, 0)
                .addComponent(jLabel4, javax.swing.GroupLayout.DEFAULT_SIZE, 37, Short.MAX_VALUE))
        );

        jButton1.setIcon(new javax.swing.ImageIcon(getClass().getResource("/views/taco.png"))); // NOI18N

        jLabel2.setFont(new java.awt.Font("DIN Alternate", 0, 20)); // NOI18N
        jLabel2.setText("                 SNACKS ");

        javax.swing.GroupLayout jPanel5Layout = new javax.swing.GroupLayout(jPanel5);
        jPanel5.setLayout(jPanel5Layout);
        jPanel5Layout.setHorizontalGroup(
            jPanel5Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, 257, Short.MAX_VALUE)
            .addComponent(jLabel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        );
        jPanel5Layout.setVerticalGroup(
            jPanel5Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel5Layout.createSequentialGroup()
                .addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 201, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(0, 0, 0)
                .addComponent(jLabel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        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(52, 52, 52)
                .addComponent(jPanel6, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(27, 27, 27)
                .addComponent(jPanel4, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(29, 29, 29)
                .addComponent(jPanel5, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );
        jPanel2Layout.setVerticalGroup(
            jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel2Layout.createSequentialGroup()
                .addGap(41, 41, 41)
                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                    .addComponent(jPanel4, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jPanel5, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(jPanel6, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(72, Short.MAX_VALUE))
        );

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, 952, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );
    }// </editor-fold>                        

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
    }                                        

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        kiosk main  =  new kiosk();
        main.switchPanel(panelCard, "drinks");
    }                                       

    
    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel5;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JPanel jPanel4;
    private javax.swing.JPanel jPanel5;
    private javax.swing.JPanel jPanel6;
    // End of variables declaration                   

    
    


}

The main connection is highlighted in dark red

What i was trying to do is to define a new kiosk in my welcome class and reference the switchPanel method which takes a parameter of (Container container, String plName)

but anytime i try to run i get this error

run:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at views.kiosk.switchPanel(kiosk.java:27)
	at views.Welcome.jButton2ActionPerformed(Welcome.java:210)
	at views.Welcome.access$000(Welcome.java:16)
	at views.Welcome$1.actionPerformed(Welcome.java:97)
	at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
	at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
	at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
	at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
	at java.awt.Component.processMouseEvent(Component.java:6516)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
	at java.awt.Component.processEvent(Component.java:6281)
	at java.awt.Container.processEvent(Container.java:2229)
	at java.awt.Component.dispatchEventImpl(Component.java:4872)
	at java.awt.Container.dispatchEventImpl(Container.java:2287)
	at java.awt.Component.dispatchEvent(Component.java:4698)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
	at java.awt.Container.dispatchEventImpl(Container.java:2273)
	at java.awt.Window.dispatchEventImpl(Window.java:2719)
	at java.awt.Component.dispatchEvent(Component.java:4698)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:747)
	at java.awt.EventQueue.access$300(EventQueue.java:103)
	at java.awt.EventQueue$3.run(EventQueue.java:706)
	at java.awt.EventQueue$3.run(EventQueue.java:704)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
	at java.awt.EventQueue$4.run(EventQueue.java:720)
	at java.awt.EventQueue$4.run(EventQueue.java:718)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:717)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

[Dave Tolls]

That code above doesn't seem to be the same as the code in the stack trace.
Line 27 in kiosk.java is a comment line, so can't have thrown the null pointer exception.

[bernard kissi]

the code stack error is on line 22

CardLayout card = (CardLayout) container.getLayout();

[Dave Tolls]

container is null, then, which means that panelCard is null in Welcome.
Where do you think panelCard is initialised (it's hard to follow that generated code)?

[bernard kissi]

private JPanel panelCard; //  

this is my panelCard in welcome.class (line 19)

 panelCard = new javax.swing.JPanel();

line 39 in my kiosk. class (line 39)

[Dave Tolls]

panelCard in kiosk is not the same as panelCard in Welcome.

So initilaising a variable in kiosk is not going to have any effect on the one in Welcome.

So what exactly are you trying to do with this variable?
That might give us a pointer as to where it should live.

[bernard kissi]

panelCard is the parent holding my card views, so therefore before i can create a button link on a card to link to the other i have to access a parent through which i can access the child card. so i want access the panelCard object in Kiosk in my welcome.class

[Dave Tolls]

OK.
So Welcome is one panel of a CardLayout and kiosk (should be Kiosk) is another?

I would suggest a controller that sits above these two.
Neither of these classes should know that it is part of a CardLayout.  They should just have a reference to something that will handle an event that means the screen needs to change.

So, when the relevant button is pressed, this will inform the controller which will then handle the CardLayout changes.

public interface ChangeScreenListener {
    void changeScreen();
}
public class PanelController {
    public PanelController() {
        // Set up CardLayout
        kiosk.addChangeScreenListener(...);
        welcome.addChangeScreenListener(...);
    }
}

Something like the above is the concept.
That way you detach the two screens.

[bernard kissi]

Kiosk is the main Jframe holding the JPanel Forms: welcome, drinks, snacks class respectively

[Dave Tolls]

Well, that's the problem with using a GUI builder.
It makes the code almost impossible (for me at least) to follow.

So treat the Kiosk as the controller.
The rest still stands.