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Reinitialise a jframe

I've a main frame on which there is a side panel with some buttons, and central panel used to display the tables and data generated from buttons on the side panel and its sub-panels
On the start my central panel is blank and I want it to always return to its initial state( blank ) after each click on a button before generating any data
I've use some sort of observer pattern (I'm not so experienced) but my problem is that the central panel must display data after clicks on some buttons that are on panels that also need a click on the side panel before to be generated
I've tried to make an executable example on the following classes, my real application displays some tables on the central panel and i send the models via the update method of the observers
hope its clear for you and I hope if you can really help me
1 - the main frame:
package tests;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class MainFrame extends JFrame implements MyObserver{
private SidePanel sidePanel;
private JPanel centralPanel;
private JFrame frame;
private JLabel title;
public MainFrame(){
frame = new JFrame("TEST");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLayout(new BorderLayout());
sidePanel = new SidePanel();
sidePanel.addObserver(this);
centralPanel = new JPanel();
title = new JLabel();
initialise(0);
frame.pack();
frame.setVisible(true);
frame.setLocationRelativeTo(null);
}
private void initialise(int i) {
if( i == 0){
centralPanel.setPreferredSize(new Dimension(400,300));
centralPanel.setBackground(Color.green);
title.setText("GREEN");
centralPanel.add(title, BorderLayout.CENTER);
frame.add(sidePanel, BorderLayout.WEST);
frame.add(centralPanel, BorderLayout.CENTER);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new MainFrame();
}
});
}
#Override
public void update(int color) {
if(color == 0){
centralPanel.setBackground(Color.yellow);
title.setText("YELLOW");
}else{
centralPanel.setBackground(Color.pink);
title.setText("PINK");
}
}
}
2 - The side Panel
package tests;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
public class SidePanel extends JPanel implements MyObserver,MyObservable{
private JPanel panel;
private JButton test;
private MyObserver observer;
private ButtonPanel buttonPanel;
public SidePanel(){
panel = new JPanel();
panel.setPreferredSize(new Dimension(140, 300));
panel.setBackground(Color.blue);
panel.setLayout(new BoxLayout(panel, 0));
test = new JButton("Lunch buttons");
test.setPreferredSize(new Dimension(80,30));
buttonPanel = new ButtonPanel();
buttonPanel.addObserver(this);
test.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
buttonPanel.setVisible(true);
}
});
panel.add(Box.createVerticalGlue());
panel.add(test);
panel.add(Box.createVerticalGlue());
panel.setVisible(true);
this.add(panel, BorderLayout.CENTER);
}
#Override
public void addObserver(MyObserver obs) {
this.observer = obs;
}
#Override
public void updateObserver(MyObserver obs, int color) {
obs.update(color);
}
#Override
public void update(int color) {
updateObserver(observer, color);
}
}
3 - the buttons panel, generally the source of any data to be displayed on the central panel
package tests;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JPanel;
public class ButtonPanel extends JDialog implements MyObservable{
private JButton yellow;
private JButton orange;
private JPanel panel;
private MyObserver observer;
public ButtonPanel(){
panel = new JPanel();
panel.setPreferredSize(new Dimension(300, 40));
panel.setLayout(new FlowLayout());
this.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
this.setContentPane(panel);
yellow = new JButton("YELLOW");
yellow.setPreferredSize(new Dimension(100,30));
yellow.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
updateObserver(observer, 0);
}
});
orange = new JButton("ORANGE");
orange.setPreferredSize(new Dimension(100,30));
orange.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
updateObserver(observer, 1);
}
});
panel.add(yellow);
panel.add(orange);
pack();
setLocationRelativeTo(null);
}
#Override
public void addObserver(MyObserver obs) {
this.observer = obs;
}
#Override
public void updateObserver(MyObserver obs, int color) {
obs.update(color);
}
}
Finally, the customized observer and observable interfaces, note in the real app i use a table model not just an int - I'm not sure it's a good way -
package tests;
public interface MyObservable {
public void addObserver(MyObserver obs);
public void updateObserver(MyObserver obs, int color);
}
package tests;
public interface MyObserver {
public void update(int color);
}

CHANGED ANSWER:
In SidePanel.java add:
private MainFrame frame;
Then make your constructor take a MyFrame object as parameter. Do this:
public SidePanel(MainFrame frame){
this.frame = frame;
//rest not changed
//
}
Change the actionPerformed() of test button to:
test.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
buttonPanel.setVisible(true);
frame.initialise(0); // this line is added
}
});
In MainFrame.java:
Change sidePanel = new SidePanel(); to sidePanel = new SidePanel(this);
AND
Change private void initialise(int i) to public void initialise(int i)
This does what you are trying to achieve.

Why can this code note be run as a JFrame?

I am trying to make an applet run as a JFrame. The code I have below is simple but should work. It will run as an JApplet but when I go to RUN AS --> nothing appears.
import java.awt.*;
import java.applet.Applet;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LifeCycle extends Applet
{
private static final long serialVersionUID = 1L;
String output = "test";
String event;
public void init()
{
gui(); //I am not certain if this needs to be there.
event = "\nInitializing...";
printOutput();
}
public void start()
{
event = "\nStarting...";
printOutput();
}
public void stop()
{
event = "\nStopping...";
printOutput();
}
public void destroy()
{
event = "\nDestroying...";
printOutput();
}
private void printOutput()
{
System.out.println(event);
output += event;
repaint();
}
private void gui() {
JFrame f = new JFrame("Not resizable");
JPanel d = new JPanel();
// LifeCycle a = new LifeCycle();
// a.init();//not working
d.setLayout(new BorderLayout());
d.add(new JButton("a"));
d.add(new JButton("b"));
d.setBackground(Color.RED);
//f.add(new LifeCycle());
f.add(d);
f.setSize(545,340);
f.setResizable(false);
f.setLocationRelativeTo(null);
f.setTitle("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//a.destroy();
}
public void paint(Graphics g)
{
System.out.println("Graphics Paint Method!");
g.drawString(output, 100, 100);
}
public static void main(String[] args) {
LifeCycle l = new LifeCycle();
l.gui();
}
}
I would like to see the code that should be changed, but I cannot seem to find why this will not work. I have added to buttons to the panel to be displayed.

Don't mix AWT (Applet) with Swing components. Stick with just Swing.
Gear your class towards creating JPanels. Then you can place it in a JApplet if you want an applet or a JFrame if you want a JFrame.
Read up on use of BorderLayout -- you're adding multiple components to the default BorderLayout.CENTER position, and only one component, the last one added, will show.
For example ...
LifeCycle2.java
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JPanel;
class LifeCycle2 {
private static final int GAP = 5;
private static final int PREF_W = 545;
private static final int PREF_H = 340;
private JPanel mainPanel = new JPanel() {
#Override
public Dimension getPreferredSize() {
return LifeCycle2.this.getPreferredSize();
}
};
public LifeCycle2() {
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, GAP, 0));
buttonPanel.add(new JButton("A"));
buttonPanel.add(new JButton("B"));
buttonPanel.setOpaque(false);
JPanel flowLayoutPanel = new JPanel();
flowLayoutPanel.setOpaque(false);
flowLayoutPanel.add(buttonPanel);
mainPanel.setLayout(new BorderLayout());
mainPanel.setBorder(BorderFactory.createEmptyBorder(GAP, GAP, GAP, GAP));
mainPanel.setBackground(Color.red);
mainPanel.add(flowLayoutPanel, BorderLayout.NORTH);
}
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
public JComponent getMainPanel() {
return mainPanel;
}
}
Show as a JFrame,
LifeCycleFrame.java
import javax.swing.*;
public class LifeCycleFrame {
private static void createAndShowGui() {
LifeCycle2 lifeCycle2 = new LifeCycle2();
JFrame frame = new JFrame("LifeCycleTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(lifeCycle2.getMainPanel());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Show as an applet,
LifeCycleApplet.java
import java.lang.reflect.InvocationTargetException;
import javax.swing.JApplet;
import javax.swing.SwingUtilities;
public class LifeCycleApplet extends JApplet {
#Override
public void init() {
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
LifeCycle2 lifeCycle2 = new LifeCycle2();
getContentPane().add(lifeCycle2.getMainPanel());
}
});
} catch (InvocationTargetException | InterruptedException e) {
e.printStackTrace();
}
}
}

Add f.setVisible(true); to the end of the gui() method. Without this call your frame won't be shown.
Please read the "How to Make Frames" Tutorial

Java Swings Select Tab

I have 4 JPanels. In one of the panel I have a combo Box.Upon selecting "Value A" in combo box Panel2 should be displayed.Similarly if I select "Value B" Panel3 should be selected....
Though action Listener should be used in this context.How to make a call to another tab with in that action listener.
public class SearchComponent
{
....
.
public SearchAddComponent(....)
{
panel = addDropDown(panelList(), "panel", gridbag, h6Box);
panel.addComponentListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
ItemSelectable is = (ItemSelectable)actionEvent.getSource();
Object name=selectedString(is);
}
});
}
public static final Vector<String> panelList(){
List<String> panelList = new ArrayList<String>();
panelList.add("A");
panelList.add("B");
panelList.add("C");
panelList.add("D");
panelList.add("E");
panelList.add("F);
Vector<String> panelVector = null;
Collections.copy(panelVector, panelList);
return panelVector;
}
public Object selectedString(ItemSelectable is) {
Object selected[] = is.getSelectedObjects();
return ((selected.length == 0) ? "null" : (ComboItem)selected[0]);
}
}

Use a Card Layout. See the Swing tutorial on How to Use a Card Layout for a working example.

Try This code:
import java.awt.EventQueue;
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import javax.swing.BorderFactory;
import javax.swing.border.Border;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JComboBox;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import java.awt.Container;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class CardLayoutExample {
JFrame guiFrame;
CardLayout cards;
JPanel cardPanel;
public static void main(String[] args) {
//Use the event dispatch thread for Swing components
EventQueue.invokeLater(new Runnable()
{
#Override
public void run()
{
new CardLayoutExample();
}
});
}
public CardLayoutExample()
{
guiFrame = new JFrame();
//make sure the program exits when the frame closes
guiFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
guiFrame.setTitle("CardLayout Example");
guiFrame.setSize(400,300);
//This will center the JFrame in the middle of the screen
guiFrame.setLocationRelativeTo(null);
guiFrame.setLayout(new BorderLayout());
//creating a border to highlight the JPanel areas
Border outline = BorderFactory.createLineBorder(Color.black);
JPanel tabsPanel = new JPanel();
tabsPanel.setBorder(outline);
JButton switchCards = new JButton("Switch Card");
switchCards.setActionCommand("Switch Card");
switchCards.addActionListener(new ActionListener()
{
#Override
public void actionPerformed(ActionEvent event)
{
cards.next(cardPanel);
}
});
tabsPanel.add(switchCards);
guiFrame.add(tabsPanel,BorderLayout.NORTH);
cards = new CardLayout();
cardPanel = new JPanel();
cardPanel.setLayout(cards);
cards.show(cardPanel, "Fruits");
JPanel firstCard = new JPanel();
firstCard.setBackground(Color.GREEN);
addButton(firstCard, "APPLES");
addButton(firstCard, "ORANGES");
addButton(firstCard, "BANANAS");
JPanel secondCard = new JPanel();
secondCard.setBackground(Color.BLUE);
addButton(secondCard, "LEEKS");
addButton(secondCard, "TOMATOES");
addButton(secondCard, "PEAS");
cardPanel.add(firstCard, "Fruits");
cardPanel.add(secondCard, "Veggies");
guiFrame.add(tabsPanel,BorderLayout.NORTH);
guiFrame.add(cardPanel,BorderLayout.CENTER);
guiFrame.setVisible(true);
}
//All the buttons are following the same pattern
//so create them all in one place.
private void addButton(Container parent, String name)
{
JButton but = new JButton(name);
but.setActionCommand(name);
parent.add(but);
}
}

JLayeredPane formatting issue

I have a problem with my JLayeredPane, I am probably doing something incredibly simple but I cannot wrap my head around it. The problem i have is that all the components are merged together and have not order. Could you please rectify this as I have no idea. The order I am trying to do is have a layout like this
output
label1 (behind)
input (in Front)
import java.awt.BorderLayout;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.io.IOException;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class window extends JFrame implements KeyListener {
/**
*
*/
private static final long serialVersionUID = 7092006413113558324L;
private static int NewSize;
public static String MainInput;
public static JLabel label1 = new JLabel();
public static JTextField input = new JTextField(10);
public static JTextArea output = new JTextArea(main.Winx, NewSize);
public window() {
super("Satine. /InDev-01/");
JLabel label1;
NewSize = main.Winy - 20;
setLayout(new BorderLayout());
output.setToolTipText("");
add(input, BorderLayout.PAGE_END);
add(output, BorderLayout.CENTER);
input.addKeyListener(this);
input.requestFocus();
ImageIcon icon = new ImageIcon("C:\\Users\\" + System.getProperty("user.name") + "\\AppData\\Roaming\\.Satine\\img\\textbox.png", "This is the desc");
label1 = new JLabel(icon);
add(label1, BorderLayout.PAGE_END);
}
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_ENTER) {
try {
MainMenu.start();
} catch (IOException e1) {
System.out.print(e1.getCause());
}
}
}
#Override
public void keyReleased(KeyEvent e) {
}
#Override
public void keyTyped(KeyEvent e) {
}
}
And the main class.
import java.awt.Container;
import java.io.IOException;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
public class main {
public static int Winx, Winy;
private static JLayeredPane lpane = new JLayeredPane();
public static void main(String[] args) throws IOException{
Winx = window.WIDTH;
Winy = window.HEIGHT;
window Mth= new window();
Mth.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Mth.setSize(1280,720);
Mth.setVisible(true);
lpane.add(window.label1);
lpane.add(window.input);
lpane.add(window.output);
lpane.setLayer(window.label1, 2, -1);
lpane.setLayer(window.input, 1, 0);
lpane.setLayer(window.output, 3, 0);
Mth.pack();
}
}
Thank you for your time and I don't expect the code to be written for me, all I want is tips on where I am going wrong.

I recommend that you not use JLayeredPane as the overall layout of your GUI. Use BoxLayout or BorderLayout, and then use the JLayeredPane only where you need layering. Also, when adding components to the JLayeredPane, use the add method that takes a Component and an Integer. Don't call add(...) and then setLayer(...).
Edit: it's ok to use setLayer(...) as you're doing. I've never used this before, but per the API, it's one way to set the layer.
e.g.,
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
public class LayeredPaneFun extends JPanel {
public static final String IMAGE_PATH = "http://duke.kenai.com/" +
"misc/Bullfight.jpg";
public LayeredPaneFun() {
try {
BufferedImage img = ImageIO.read(new URL(IMAGE_PATH));
ImageIcon icon = new ImageIcon(img);
JLabel backgrndLabel = new JLabel(icon);
backgrndLabel.setSize(backgrndLabel.getPreferredSize());
JPanel forgroundPanel = new JPanel(new GridBagLayout());
forgroundPanel.setOpaque(false);
JLabel fooLabel = new JLabel("Foo");
fooLabel.setFont(fooLabel.getFont().deriveFont(Font.BOLD, 32));
fooLabel.setForeground(Color.cyan);
forgroundPanel.add(fooLabel);
forgroundPanel.add(Box.createRigidArea(new Dimension(50, 50)));
forgroundPanel.add(new JButton("bar"));
forgroundPanel.add(Box.createRigidArea(new Dimension(50, 50)));
forgroundPanel.add(new JTextField(10));
forgroundPanel.setSize(backgrndLabel.getPreferredSize());
JLayeredPane layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(backgrndLabel.getPreferredSize());
layeredPane.add(backgrndLabel, JLayeredPane.DEFAULT_LAYER);
layeredPane.add(forgroundPanel, JLayeredPane.PALETTE_LAYER);
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
add(new JScrollPane(new JTextArea("Output", 10, 40)));
add(layeredPane);
} catch (MalformedURLException e) {
e.printStackTrace();
System.exit(1);
} catch (IOException e) {
e.printStackTrace();
System.exit(1);
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("LayeredPaneFun");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new LayeredPaneFun());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

how to change UI depending on combo box selection

In dialog I need to display one group of controls if some combo is checked and another group of controls otherwise.
I.e. I need 2 layers and I need to switch between them when combo is checked/unchecked. How can I do that?
Thanks

CardLayout works well for this, as suggested below.
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/** #see http://stackoverflow.com/questions/6432170 */
public class CardPanel extends JPanel {
private static final Random random = new Random();
private static final JPanel cards = new JPanel(new CardLayout());
private static final JComboBox combo = new JComboBox();
private final String name;
public CardPanel(String name) {
this.name = name;
this.setPreferredSize(new Dimension(320, 240));
this.setBackground(new Color(random.nextInt()));
this.add(new JLabel(name));
}
#Override
public String toString() {
return name;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
create();
}
});
}
private static void create() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
for (int i = 1; i < 9; i++) {
CardPanel p = new CardPanel("Panel " + String.valueOf(i));
combo.addItem(p);
cards.add(p, p.toString());
}
JPanel control = new JPanel();
combo.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JComboBox jcb = (JComboBox) e.getSource();
CardLayout cl = (CardLayout) cards.getLayout();
cl.show(cards, jcb.getSelectedItem().toString());
}
});
control.add(combo);
f.add(cards, BorderLayout.CENTER);
f.add(control, BorderLayout.SOUTH);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}