SWING: CardLayout Class Cheat Sheet - A quick cheatsheet for beginners, with examples

Following is the declaration for java.awt.CardLayout class

public class CardLayout
   extends Object
      implements LayoutManager2, Serializable

# Constructors

CardLayout()	Creates a new card layout with the gaps of size zero.
CardLayout(int hgap, int vgap)	Creates a new card layout with the specified horizontal and vertical gaps.

# Methods

`void addLayoutComponent(Component comp, Object constraints)`	Adds the specified component to this card layout’s internal table of names.
`void addLayoutComponent(String name, Component comp)`	If the layout manager uses a per-component string, adds the component comp to the layout, associating it with the string specified by name.
`void first(Container parent)`	Flips to the first card of the container.
`int getHgap()`	Gets the horizontal gap between the components.
`float getLayoutAlignmentX(Container parent)`	Returns the alignment along the x axis.
`float getLayoutAlignmentY(Container parent)`	Returns the alignment along the y-axis.
`int getVgap()`	Gets the vertical gap between the components.
`void invalidateLayout(Container target)`	Invalidates the layout, indicating that if the layout manager has cached information it should be discarded.
`void last(Container parent)`	Flips to the last card of the container.
`void layoutContainer(Container parent)`	Lays out the specified container using this card layout.
`Dimension maximumLayoutSize(Container target)`	Returns the maximum dimensions for this layout given the components in the specified target container.
`Dimension minimumLayoutSize(Container parent)`	Calculates the minimum size for the specified panel.
`void next(Container parent)`	Flips to the next card of the specified container.
`Dimension preferredLayoutSize(Container parent)`	Determines the preferred size of the container argument using this card layout.
`void previous(Container parent)`	Flips to the previous card of the specified container.
`void removeLayoutComponent(Component comp)`	Removes the specified component from the layout.
`void setHgap(int hgap)`	Sets the horizontal gap between the components.
`void setVgap(int vgap)`	Sets the vertical gap between the components.
`void show(Container parent, String name)`	Flips to the component that was added to this layout with the specified name, using addLayoutComponent.
`String toString()`	Returns a string representation of the state of this card layout.

# Methods Inherited

java.lang.Object

# CardLayout Example

SwingLayoutDemo.java

package com.simplecheatsheet.gui;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SwingLayoutDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;
   private JLabel msglabel;
   public SwingLayoutDemo(){
      prepareGUI();
   }
   public static void main(String[] args){
      SwingLayoutDemo swingLayoutDemo = new SwingLayoutDemo();  
      swingLayoutDemo.showCardLayoutDemo();       
   }
   private void prepareGUI(){
      mainFrame = new JFrame("Java SWING Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      headerLabel = new JLabel("",JLabel.CENTER );
      statusLabel = new JLabel("",JLabel.CENTER);        
      statusLabel.setSize(350,100);
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      controlPanel = new JPanel();
      controlPanel.setLayout(new FlowLayout());
      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }
   private void showCardLayoutDemo(){
      headerLabel.setText("Layout in action: CardLayout");      
      final JPanel panel = new JPanel();
      panel.setBackground(Color.CYAN);
      panel.setSize(300,300);
      CardLayout layout = new CardLayout();
      layout.setHgap(10);
      layout.setVgap(10);
      panel.setLayout(layout);        
      JPanel buttonPanel = new JPanel(new FlowLayout());
      buttonPanel.add(new JButton("OK"));
      buttonPanel.add(new JButton("Cancel"));    
      JPanel textBoxPanel = new JPanel(new FlowLayout());
      textBoxPanel.add(new JLabel("Name:"));
      textBoxPanel.add(new JTextField(20));
      panel.add("Button", buttonPanel);
      panel.add("Text", textBoxPanel);
      final DefaultComboBoxModel panelName = new DefaultComboBoxModel();
      panelName.addElement("Button");
      panelName.addElement("Text");
      final JComboBox listCombo = new JComboBox(panelName);    
      listCombo.setSelectedIndex(0);
      JScrollPane listComboScrollPane = new JScrollPane(listCombo);    
      JButton showButton = new JButton("Show");
      showButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) { 
            String data = "";
            if (listCombo.getSelectedIndex() != -1) {  
               CardLayout cardLayout = (CardLayout)(panel.getLayout());
               cardLayout.show(panel, 
                  (String)listCombo.getItemAt(listCombo.getSelectedIndex()));            
            }              
            statusLabel.setText(data);
         }
      }); 
      controlPanel.add(listComboScrollPane);
      controlPanel.add(showButton);
      controlPanel.add(panel);
      mainFrame.setVisible(true);  
   }
}

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