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Create object on Jbutton click

I am trying to create an object when the user presses the button.So far, I've come up with the implementation bellow, but it does not seem to work.I haven't been dealing with Swing and Java UI at all so I am guessing it might be an amateur mistake.
The object I am trying to create is from another type called DebitCard.
private JFrame frame;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
GenerateCard window = new GenerateCard();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public GenerateCard() {
}
{
frame = new JFrame();
frame.setBounds(100, 100, 450, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JButton btnNewButton = new JButton("Generate card");
btnNewButton.setBounds(112, 213, 216, 41);
frame.getContentPane().add(btnNewButton);
}
private class buttonEvent implements ActionListener {
public void actionPerformed(ActionEvent e) {
String command = e.getActionCommand();
if (command.equals("Generate card")) {
DebitCard a = new DebitCard();
}
}
}

Based on your available code, you seem to have forgotten to register buttonEvent with btnNewButton
btnNewButton.addActionListener(new buttonEvent());
You might want to take a closer look at:
How to Use Buttons, Check Boxes, and Radio Buttons
How to Write an Action Listener
Laying Out Components Within a Container
Code Conventions for the Java TM Programming Language (this will make your code easier to read and it easier for you to read others)

Java Child Object run Parent Object s method

I decided using BorderLayout for swing design named Loginwards. And I wrote 5 Classes for 5 side of BorderLayout as PageStart, LineStart, Center, LineEnd, PageEnd.
I have undecorated Loginwards and designed PageStart for use minimize,resize,quit.(for my own images, rules...) button quit is simple because it have worked like this
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
System.exit(0);
}
});
but for example minimize I could not solve. I should have changed my Loginwards properties from another class object
Sum up
public class Loginwards extends Jframe
{ ...
JFrame frame = new JFrame("BorderLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(PageStart.Panel(), BorderLayout.PAGE_START);
...
}
public class PageStart{
public static JPanel Panel(){
JPanel panel = new JPanel();
FlowLayout pagestart = new FlowLayout(FlowLayout.RIGHT);
panel.setLayout(pagestart);
panel.add(MinimizeButton());
panel.add(ResizeButton());
panel.add(QuitButton());
}
public static JButton MinimizeButton(){
JButton button = new JButton();
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
// I Should be able to reach Loginwards here.
}
});
return button;
}

MinimizeButton is a static method, so pass Loginwards instance as it's parameter, then make use of it in your listener:
public static JButton MinimizeButton(Loginwards loginwards){
JButton button = new JButton();
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
// Invoke whatever you need on Loginwards...
loginwards.doSomething();
}
});
return button;
}
Btw, method names should start with lowercase... see naming conventions for Java

How to dynamically create JPanel with given parameters?

I have main JFrame in my project. And one main JPanel with Y-AXIS BoxLayout which is used to contain another panels in it. This is the way i use my JFrame to show this JPanel by default (I'm not quite convinced if this is the right way):
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
mainPanel = new MainScreenPanel();
MainFrame mainFrame = new MainFrame();
mainFrame.setContentPane(mainPanel);
mainFrame.invalidate();
mainFrame.validate();
mainFrame.setVisible(true);
}
});
}
Next I add two JPanels into mainPanel like this:
public class MainScreenPanel extends javax.swing.JPanel {
public MainScreenPanel() {
StatusPanel sPanel = new StatusPanel();
LogPanel lPanel = new LogPanel();
add(sPanel);
add(lPanel);
}
}
lPanel has different gui elements on it. One of them is a button which opens another panel (addConnectionPanel), and replaces mainPanel in the jFrame Here is the way i do it:
private void addCnctButtonActionPerformed(java.awt.event.ActionEvent evt) {
JFrame topFrame = (JFrame) SwingUtilities.getWindowAncestor(this);
topFrame.setContentPane(new AddConnectionPanel());
topFrame.invalidate();
topFrame.validate();
}
AddConectionPanel has some labels and input text boxes. It has two buttons ok and cancel. Here is the code of cancel button:
private void cancelCnctBtnActionPerformed(java.awt.event.ActionEvent evt) {
JFrame topFrame = (JFrame) SwingUtilities.getWindowAncestor(this);
topFrame.setContentPane(new MainScreenPanel());
topFrame.invalidate();
topFrame.validate();
}
sPanel is empty. It must be empty until input boxes on AddConnectionPanel are not filled and 'ok' button is not pressed. When these actions are performed, I want to dynamically create JLabels which take parameters from inputs on sPanel. Labels should be grouped, so when the actions performed second time new group must be created. Can some one give me advice on how to do this? And show me my mistakes? Keep in mind I'm using NetBeans.

This would be my approach:
public interface ConnectionPanelListener{
void onOkButtonClicked(String... options);
void onCancelButtonClicked();
}
public class AddConnectionPanel extends JPanel {
private static final long serialVersionUID = 1L;
private ConnectionPanelListener listener;
public AddConnectionPanel(){
final Map<ConnectionOptions, JTextField> components = new HashMap<>(ConnectionOptions.values().length);
for(ConnectionOptions option:ConnectionOptions.values()){
this.add(new JLabel(option.labelCaption));
JTextField textField = new JTextField();
//setup textField;
this.add(textField);
components.put(option, textField);
}
JButton button = new JButton("OK");
button.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(final MouseEvent pE) {
super.mouseClicked(pE);
//TODO validate TextFields
Collection<String> inputs = new Stack<>();
for(Entry<?,JTextField> e : components.entrySet()){
String text = e.getValue().getText();
if(text==null || text.trim().isEmpty()){
//TODO improve input validation
System.out.println("Input text is empty for: "+e.getKey());
} else {
inputs.add(e.getKey() + ": " + text);
}
}
listener.onOkButtonClicked(inputs.toArray(new String[inputs.size()]));
}
});
this.add(button);
button = new JButton("cancel");
button.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(final MouseEvent pE) {
super.mouseClicked(pE);
listener.onCancelButtonClicked();
}
});
this.add(button);
}
public void setConnectionPanelListener(final ConnectionPanelListener l){
listener = l;
}
private enum ConnectionOptions{
IP_ADDRESS("IP-Address:"), PORT("Port:"), WHATEVER_ATTRIBUTE_YOU_NEED("Extras:");
private String labelCaption;
private ConnectionOptions(final String caption) {
labelCaption = caption;
}
}
}
As you can see, AddConnectionPanel expects a Listener to register for the case, that "OK" or "CANCEL" are clicked. So your adjusted implementation could be like:
private void addCnctButtonActionPerformed(java.awt.event.ActionEvent evt) {
JFrame topFrame = (JFrame) SwingUtilities.getWindowAncestor(this);
AddConnectionPanel panel = new AddConnectionPanel();
panel.setConnectionPanelListener(new ConnectionPanelListener(){
#Override
void onOkButtonClicked(String... options){ TODO: fill sPanel using the given Strings }
#Override
void onCancelButtonClicked(){ TODO }
});
topFrame.setContentPane(panel);
topFrame.invalidate();
topFrame.validate();
}

Passing values between classes

I have a JPanel form which contains a JList and some JButton.
The JPanel looks like this
When I click the Add List button, a separate JFrame form is displayed.
The JFrame form will look like this
When the add button on the JFrame is clicked, I need to add the value of the JTextfield (named List Name) to the JList on the previous JPanel. I wonder how to pass the value from the JFrame to the JPanel? Any suggestion would be appreciated.
Here is a code of the JPanel form (using Designer GUI)
package multimediaproject;
public class musicPlayerPanel extends javax.swing.JPanel {
public musicPlayerPanel() {
initComponents();
}
private void initComponents() {
//...here is the generated code by using designer GUI
}
// Variables declaration - do not modify
//..generated code
// End of variables declaration
}
Here is the code of JFrame form (using Designer GUI)
package multimediaproject;
public class addListFrame extends javax.swing.JFrame {
public addListFrame() {
initComponents();
this.setLocation(515, 0);
setVisible(true);
}
private void initComponents() {
//..here is the generated code by using Designer GUI
}
private void addBtnActionPerformed(java.awt.event.ActionEvent evt){
//some validation
if(...)
{
//validation
}
else
{
//IF VALUE IS CORRECT, ADD the List Name JTextfield value to the JList on the previous JPanel
errorMessage.setText("");
}
}
public static void main(String args[]) {
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new addListFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
//....generated code
// End of variables declaration
}

UPDATE with your code.
You can take advantage of PropertyChangeListener and PropertyChangeSupport (This classes implements Observer Pattern).
I give you an example you for guidance:
public class MusicPlayerPanel extends JPanel {
private JList list;
private JButton addButton;
private PropertyChangeListener listener = new MyPropertyChangeListener();
//..in some place
addButton.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e){
JFrame form = new FrameForm();
form.addPropertyChangeListener(FrameForm.BUTTON_CLICKED,listener);
form.setVisible(true);
}
});
//in another place
private class MyPropertyChangeListener implements PropertyChangeListener{
#Override
public void propertyChange(PropertyChangeEvent evt){
if(evt == null)
return;
if(evt.getPropertyName().equals(FrameForm.BUTTON_CLICKED)){
String value = (String) evt.getNewValue();
((DefaultListModel)list.getModel()).addElement(value);
}
}
}
}
And the frame form like this:
public class AddListFrame extends JFrame{
private JTextField textfield;
private JButton submitButton;
public static final String BUTTON_CLICKED ="buttonClicked";
// in some place
submitButton.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent evt){
firePropertyChange(BUTTON_CLICKED,null,textfield.getText());
}
});
}
Note: In java by convention, classes start with uppercase and follow a camel style. This is very important for readability.

OK.This is easy if i understand your problem.
Step 1:Create setter and getter for your JList object reference.
Step 2:On button click , when you open new JFrame pass your panel reference in constructor of class which inherits JFrame.
Step 3:By doing this you are able to call getter method on panel reference.
Step 4:Now you have reference of JList,do what you want.
I hope this is best solution of your problem

"when I click the add button, a separate jFrame form is displayed. The jFrame contain a jTextfield and a submit button."
Did you seriously create an entirely new JFrame for a JTextField and a JButton?!
Have you not heard of JOptionPane? That's exactly what you are trying to replicate. The only code you need is this:
String s = JOptionPane.showInputDialog(component, message);
model.addElement(s);
The first line will cover all your code for your custom JFrame.
Take a look at this example
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class JOPDemo extends JPanel {
JList list;
JButton button = new JButton("Add Name");
String name;
DefaultListModel model;
public JOPDemo() {
model = new DefaultListModel();
list = new JList(model);
setLayout(new BorderLayout());
add(list, BorderLayout.CENTER);
add(button, BorderLayout.SOUTH);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
name = JOptionPane.showInputDialog(this, "Enter a name");
model.addElement(name);
}
});
}
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
private static void createAndShowGui() {
JFrame frame = new JFrame();
frame.add(new JOPDemo());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Edit
What you can do is have an inner class which is your JFrame. Personally, I'd go with a JDialog though.
From comment: Have your frame as an inner class of your main class. That way it can access all the variables from your main class. You can have a String listName also in the GUI class. From the other frame when you hit add, it sets the listName in GUI class, then adds to the list.
public class GUI {
String listName;
JList list;
InnerFrame inner = new InnerFrame();
private class InnerFrame extends JFrame {
JButton addButton;
}
}

How can i set different action commands while implementing an action listener?

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class Menu extends JFrame implements ActionListener{
// Create the components and global variables
JButton newGameButton = new JButton("New Game");
JButton instructionGameButton = new JButton("Instructions");
JButton exitButton = new JButton("Exit");
JLabel mylabel = new JLabel("Welcome to Blackjack");
public Menu()
{
// Create the window
super("ThreeButtons");
setSize(300,100);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
//Creating the container for the components and set the layout
Container content = getContentPane();
FlowLayout layout = new FlowLayout();
content.setLayout(layout);
//Adding the event listener
newGameButton.addActionListener(this);
instructionGameButton.addActionListener(this);
exitButton.addActionListener(this);
//Adding of components
content.add(mylabel);
content.add(newGameButton);
content.add(instructionGameButton);
content.add(exitButton);
setContentPane(content);
}
//Add the event handler
public void actionPerformed(ActionEvent event)
{
if (event.getActionCommand()=="New Game")
new lol4();
if (event.getActionCommand()=="Instructions")
//new Instructions();
if (event.getActionCommand()=="Quit ?")
System.exit(0);
}
public static void main (String[] args)
{
//Create an instance of my class
new Menu();
}
}
Exit does not seem to work

First of all, never use "==" to compare Strings. Use the equals(...) method.
Exit does not seem to work
Why do you check for "Quit ?"?
The action command defaults to the text of the button, unless you set the command explicitly.

I never liked the "switch-board" action listeners where the listener tries to do everything and risks doing nothing due to hard to fix bugs. Better I think to use anonymous inner classes either to hold simple code themselves, or if more complex to route code to other methods, or if still more complex, to call a Controller's method.
For example:
newGameButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
newGameActionPerformed(); // delegate this to a class method
}
});
instructionGameButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// call a controller object's methods
if (myController != null) {
myController.instructionGameAction();
}
}
});
exitButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Menu.this.dispose(); // simple code can be called in-line
}
});
and elsewhere in the class:
private void newGameActionPerformed() {
// TODO add some code here!
}
public void setController(MyController myController) {
this.myController = myController;
}