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How to change 'card' in Jframe cardlayout from Jpanel which belonging to card and its placed in another class?

I have written a jframe with cardlayout as in the following code :
public class Gui extends JFrame {
private static CardLayout cardlayout = new CardLayout();
private static JPanel cards = new JPanel(cardlayout);
public Gui() {
cards.setLayout(cardlayout);
CasaPanel card =new CasaPanel();
cards.add(card,"casa");
InCash card_1 = new InCash();
cards.add(card_1,"in");
OutCash card_2 = new OutCash();
cards.add(card_2,"out");
setLayout(new BorderLayout());
add(cards, BorderLayout.CENTER);
}
public static void showCard(String name)
{
cardlayout.show(cards, name);
}
i'm trying to call method to change card (ShowCard) from one of the JPanel(CasaPanel) , which is itself a 'card'. I want change a 'card' after clicking a button in a JPanel(CasaPanel) which is in another class. How to do this?I mean i know how to add button and listener but i don't know if is it possible to call a method in JFrame from a Jpanel class belonging to that frame ? How to refer to method in JFrame from other classes? I looked at this question but i really don't want put all code in one class.

Your "card" is added to the panel which uses the CardLayout. If you want to change cards then you just need access to the layout mananger. So from your panel you can use the getParent() method to get the parent panel and then use the getLayout() method to get the CardLayout.
So the code in the ActionListener might be something like:
JPanel parent = (JPanel)getParent();
CardLayout layout = parent.getLayout();
layout.show(panel, "...");
Also, then general design on your class is wrong. You should NOT be using static methods. Read the section from the Swing tutorial on How to Use CardLayout for working examples and a better way to structure your code.

Cannot use JFrame method from mouselistener

I am currently trying developing simple game, but having some trouble with making game menu. I use JPanel for each states in game menu such as instruction or option and have method in parent JFrame to shuffle them according to what item user click on the menu.
My code is like this (without some simple method like setSize() or setVisible() ).
public class Game extends JFrame{
private JPanel mainPanel = new MainPanel();
private JPanel helpPanel; = new HelpPanel();
private JPanel optionPanel = new OptionPanel();
private JPanel currentPanel = new JPanel();
public Game(){
add(currentPanel);
}
public void changePanel(int destination){
remove(currentPanel);
if(destination==MAIN_PANEL)
currentPanel = mainPanel;
else if(destination==HELP_PANEL)
currentPanel = helpPanel;
else if(destination==OPTION_PANEL)
currentPanel = optionPanel;
add(currentPanel);
}
Everything work perfectly except when I try to use changePanel method in mouselistener, it wasn't responded anything. Then I try some simple method like this.
....
public void mouseClicked(MouseEvent e) {
removeAll();
JOptionPane.showConfirmDialog(null, "Pop when click anywhere.");
}
....
I expected my JFrame would be cleared and the dialog poped. The dialog does pop but for JFrame. My question is how can I use those simple method from mouselistener.
Sorry for my terrible English. I am now learning both Java and English.

Don't use a MouseListener.
I can't tell exactly what you are doing but you should probably be using either a JMenuBar with menus or JButtons. In any case I suggest you start by reading the Swing tutorial to learn the basics of Swing. There are sections on:
How to Use Menus
How to Use Buttons
to get your started.
Also you should check out the section on Using a Card Layout. This is generally the better approach when you want to remove/add panels from a frame.

How to add external JPanel in JFrame?

I'm working on large scale program. As you can see I have one main JFrame and about 20 menu items on that. Each menu item must pop up a new window. At the beginning I have created a JLayeredPanel and then I assigned each menu item to one JPanel which is inside JFrame.Then I put 25 panel in JLayeredPanel... Default all the panels are set to invisible like:
panel1.setVisible(false);
panel2.setVisible(false);
so on
When user click on one menu item, its JPanel will be visible and rest are invisible. It looks messy and I have 5000 lines code. I used InternalFrame and TabbedPane but I'm not happy with them. I want to split my code in different JPanel classes and assign them to the main JFrame. I mean when user clicked on each menu item it will call the external JPanel and render it on the JPanel on the main JFrame. I am using design mode in netbeans and it does everything for me but the simpled structure is like this and it is not working:
public class NewJPanel extends JPanel{
//I have added buttons and etc on this panel
......
}
public class frame extends JFrame(){
JPanel panel = new JPanel();
.....
Public frame(){
frame.add(panel);
}
......
//When use click on the any button on the panel
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//this is not working
NewJPanel fi = new NewJPanel ();
panel1.add(fi);
//or I tested this way separately but it did not work
panel1.remove();
panel1 = new NewJPanel();
add(panel);
invalidate();
}
}
please give me any suggestion how I can control this program in splited classes in professional way.

remove JPanel from JFrame.getContentPane.remove(myPanel)
add a new JPanel with constants, everyhing depends of used LayoutManager and its methods implemented in API
call JFrame.(re)validate() and JFrame.repaint() as last code lines, if everything is done, these notifiers correctly repaint available area
again to use CardLayout, there isn't signoficant performance or memory issue

Please give me any suggestion how I can control this program in splited classes in proressional way.
Ok.
You should put all of your JPanels in a JTabbedPane. The JTabbedPane would be added to the JFrame.
The JFrame, JTabbedPane, and each JPanel would be constructed in a separate class.
You use Swing components, rather than extending them. The only reason you extend a Swing component is if you override one of the component methods.
You should also create model classes for each of the JPanels, as well as a model class for the application.
Read this article to see how to put a Swing GUI together.

make's code better
public class NewJPanel extends JPanel{
//I have added buttons and etc on this panel
......
}
public class frame extends JFrame(){
JPanel panel = new JPanel();
.....
Public frame(){
//frame.add(panel); you dont need call frame because extends JFrame in frame class
add(panel);
......
//When use click on the any button on the panel
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//this is not working
NewJPanel fi = new NewJPanel();
add(fi);
//or I tested this way separately but it did not work
/*panel1.remove();
panel1 = new NewJPanel();
add(panel);
invalidate();you must define panel1 before use it,like :JPanel panel1 = new JPanel();*/
}
}

Adding jlabel to a jframe using components

I have 2 classes,
My main class creates a frame and I want another class to add content to it. A bit of reading arroudn told me I should use components to do this however when I run my code the frame is empty.
public static void main(String[] args)
{
// create frame
JFrame frame = new JFrame();
final int FRAME_WIDTH = 800;
final int FRAME_HEIGHT = 600;
// set frame attributes
frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
frame.setTitle("My Frame");
frame.setVisible(true);
Component1 Com = new Component1();
Component add = frame.add(Com);
}
My Component class creates a JLabel
public class Component1 extends JComponent {
public void paintComponent()
{
JLabel label = new JLabel("<html>Some Text</html>");
}
}
I don't get any compile errors, however I dont get any text in my JFrame.
Can anyone explain what I'm doing wrong?
Chris

You need to add the JLabel. Also better to extend JPanel instead of JComponent as it has a default layout manager and will make any added components appear without the need to set component sizes. paintComponent is used for custom painting BTW.
public class Component1 extends JPanel {
Component1() {
JLabel label = new JLabel("<html>Some Text</html>");
add(label);
}
}

No need to create a new Component. Just call frame.getContentPane().add(label). And initialize your label before this.

Difficulty removing all components from a Jpanel

G'day all,
I am coding a main menu for a project. The menu displays properly. I have also set up ActionListeners for the three buttons on the menu.
What I wish to do is reuse the JPanel for a new set of radio buttons when the user chooses "Start a New Game".
However, coding ActionPerformed to remove the existing components from the JPanel has me stumped. I know removeAll is somehow important, but unfortunately NetBeans informs me I cannot call it on my mainMenu JPanel object within ActionPerformed. So i have commented it out in my code below, but left it in so you can see what I am trying to do.
Your thoughts or hints are appreciated.
Here is my main code:
public class Main {
public static void main(String[] args) {
MainMenu menu = new MainMenu();
menu.pack();
menu.setVisible(true);
}
}
Here is my mainMenu code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class MainMenu extends JFrame implements ActionListener {
JButton startNewGame = new JButton("Start a New Game");
JButton loadOldGame = new JButton("Load an Old Game");
JButton seeInstructions = new JButton("Instructions");
public MainMenu() {
super("RPG Main Menu");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainMenu = new JPanel();
mainMenu.setLayout(new FlowLayout());
startNewGame.setMnemonic('n');
loadOldGame.setMnemonic('l');
seeInstructions.setMnemonic('i');
startNewGame.addActionListener(this);
loadOldGame.addActionListener(this);
seeInstructions.addActionListener(this);
mainMenu.add(startNewGame);
mainMenu.add(loadOldGame);
mainMenu.add(seeInstructions);
setContentPane(mainMenu);
}
public void actionPerformed(ActionEvent evt) {
Object source = evt.getSource();
if (source == startNewGame) {
// StartNewGame code goes here
// mainMenu.removeAll();
}
if (source == loadOldGame) {
// LoadOldGame code goes here
}
if (source == seeInstructions) {
// Quit code goes here
}
}
}

Consider using a CardLayout instead, which manages two or more components (usually JPanel instances) that share the same display space. That way you don't have to fiddle with adding and removing components at runtime.

You need mainMenu to be a member variable:
public class MainMenu extends JFrame implements ActionListener {
JButton startNewGame = new JButton("Start a New Game");
JButton loadOldGame = new JButton("Load an Old Game");
JButton seeInstructions = new JButton("Instructions");
JPanel mainMenu = new JPanel();
Why do you feel the need to re-use this object?

You don't have a reference to mainMenu actionPerformed use. If you declare mainMenu with the buttons. It would work.

The problem is that the actionPerformed method is trying to call the JPanel mainMenu which is out of scope, i.e. the mainMenu variable is not visible from the actionPerformed method.
One way to get around this is to have the JPanel mainMenu declaration in the class itself and make it an instance field which is accessible to all instance methods of the class.
For example:
public class MainMenu extends JFrame implements ActionListener
{
...
JPanel mainMenu;
public MainMenu()
{
...
mainMenu = new JPanel();
...
}
public void actionPerformed(ActionEvent e)
{
...
mainMenu.removeAll();
}
}

Avoid attempting to "reuse" stuff. Computers are quite capable of tidying up. Concentrate on making you code clear.
So instead of attempting to tidy up the panel, simply replace it with a new one.
Generally a better way to write listeners is as anonymous inner classes. Code within these will have access to final variables in the enclosing scope and to members of the enclosing class. So, if you make mainMenu final and you ActionListeners anonymous inner classes, your code should at least compile.
Also don't attempt to "reuse" classes. Try to make each class do one sensible thing, and avoid inheritance (of implementation). There is almost never any need to extend JFrame, so don't do that. Create an ActionListener for each action, rather than attempting to determine the event source.
Also note, you should always use Swing components on the AWT Event Dispatch Thread. Change the main method to add boilerplate something like:
public static void main(final String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() { public void run() {
runEDT();
}});
}