Daniel Daniel - 1 month ago 10
Java Question

How to use buttons to switch to a specific JPanel?

Instead of going to the next panel using JPanel().next and JPanel().previous I'd like to switch to a specific panel using a button.

Say I have 3 pages, by using the button labelled 'Go to page 3', it will take me to a panel I have created for page 3; and on that page I'd have more buttons that would take me back to page 1, or page 2 even. Say if I had a tenth page, a button could take me straight to it and I wouldn't have to click a next button.

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 CardLayoutExample
{
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 are 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 page1Button = new JButton("Go to page 1");
final JButton page5Button = new JButton("Go to Page 5");
final JButton page10Button = new JButton("Go to Page 10");
buttonPanel.add(page1Button);
buttonPanel.add(page5Button);
buttonPanel.add(page10Button);

/* Adding the ActionListeners to the JButton,
* so that the user can see the next Card or
* come back to the previous Card, as desired.
*/
page1Button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
CardLayout cardLayout = (CardLayout) contentPane.getLayout();
cardLayout.previous(contentPane);
}
});
page5Button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
CardLayout cardLayout = (CardLayout) contentPane.getLayout();
cardLayout.next(contentPane);
}
});

//page10Button.addActionListener(new ActionListener();
//Code to navigate to page 10...

// 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();
}
});
}
}


I have my methods set up for when I click a button, but it only navigates to the next page, not the one I want.

What other alternatives of .next and .previous are there? I want to go to a specific page.

Thanks for your help.

Answer

When adding to a card layout, you can specify a "key" that you can reference later when attempting to show a specific panel. The sample below should get you started:

CardLayout myCardLayout = new CardLayout();
JPanel myCardLayoutPanel = new JPanel(myCardLayout);
myCardLayoutPanel.add(myComponent, "A_KEY");
myCardLayout.show(myCardLayoutPanel,"A_KEY");

Additionally you should check out the docs

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