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How to copy JButton action and change its references to underlying objects?

The following example creates a JFrame with JButton, JTextField and JLabel.
When the button is pressed it increments the value in the text field and label.
This example also creates a 2nd JFrame that is a copy of the first.
The button, text field and label is copied as well.
The issue at hand is the button on the copied frame still updates the text field and label on the original. The 'why' is fairly obvious and is because the code makes specific reference to the text field and label.
Although this isn't written in the best manner but it is a great example of the scenario in which I am addressing.
The objective is, without a major rewrite, what would be the least invasive way to have the copied button action update the copied test field and label instead of the original?
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
class ButtonTextFieldLabel extends JFrame
{
JButton bnt1 = new JButton("B1");
JTextField tf1 = new JTextField("1");
JLabel lbl1 = new JLabel("100");
public ButtonTextFieldLabel()
{
super("Main Frame");
setLayout(null);
bnt1.setBounds(50,100,120,40);
tf1.setBounds(300,100, 80,40);
lbl1.setBounds(200,100,80,40);
bnt1.addActionListener(new ListenerHolder(this));
add(bnt1);
add(tf1);
add(lbl1);
setSize(500,500);
makeCopy(this);
setVisible(true);
}
private void makeCopy(ButtonTextFieldLabel originalObj)
{
JFrame copyFrame = new JFrame();
copyFrame.setTitle("Copy of " + originalObj.getTitle());
copyFrame.setSize(originalObj.getSize());
copyFrame.setLocation(originalObj.getX()+100, originalObj.getY()+100);
copyFrame.setLayout(null);
JButton copyBnt1 = new JButton();
copyBnt1.setBounds(originalObj.bnt1.getBounds());
copyBnt1.setLabel(originalObj.bnt1.getLabel());
copyFrame.add(copyBnt1);
for (ActionListener al : originalObj.bnt1.getActionListeners())
{
copyBnt1.addActionListener(al);
}
JTextField copyTf1 = new JTextField();
copyTf1.setBounds(originalObj.tf1.getBounds());
copyTf1.setText(originalObj.tf1.getText());
JLabel copyLbl1 = new JLabel();
copyLbl1.setBounds(originalObj.lbl1.getBounds());
copyLbl1.setText(originalObj.lbl1.getText());
copyFrame.add(copyBnt1);
copyFrame.add(copyTf1);
copyFrame.add(copyLbl1);
copyFrame.setVisible(true);
}
public void runThis()
{
tf1.setText( Integer.toString(Integer.parseInt(tf1.getText())+1) );
lbl1.setText( Integer.toString(Integer.parseInt(lbl1.getText())+1) );
}
}
class ListenerHolder implements ActionListener
{
ButtonTextFieldLabel ph;
public ListenerHolder(ButtonTextFieldLabel ph)
{
this.ph = ph;
}
#Override
public void actionPerformed(ActionEvent arg0)
{
ph.runThis();
}
}
public class TestBTL
{
public static void main(String[] args){
new ButtonTextFieldLabel();
}
}

You already know the reason for the problem -- you're copying the original ActionListener, complete with its reference to the original GUI components. The overall solution is not to copy the action listener but rather to create your GUI's to hold and maintain their own unique state. One solution is rather than try to copy components via kludge, to create a self-contained GUI object that holds and updates its own state. You can create multiple GUI's using a factory method if desired.
For example:
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class TestBtl2 {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
createAndDisplayFrame("Frame 1").setVisible(true);
createAndDisplayFrame("Frame 2").setVisible(true);
});
}
// Factory method
private static JFrame createAndDisplayFrame(String text) {
BtlPanel btlPanel = new BtlPanel();
JFrame frame = new JFrame(text);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(btlPanel);
frame.pack();
frame.setLocationByPlatform(true);
return frame;
}
}
class BtlPanel extends JPanel {
private int value = 0;
private JButton button1 = new JButton(new ButtonAction("Button 1"));
private JLabel label1 = new JLabel("00");
private JTextField textField1 = new JTextField("00");
public BtlPanel() {
textField1.setFocusable(false);
add(button1);
add(Box.createHorizontalStrut(20));
add(label1);
add(Box.createHorizontalStrut(20));
add(textField1);
setPreferredSize(new Dimension(300, 100));
}
public void incrementValue() {
value++;
String text = String.format("%02d", value);
label1.setText(text);
textField1.setText(text);
}
private class ButtonAction extends AbstractAction {
public ButtonAction(String name) {
super(name);
}
#Override
public void actionPerformed(ActionEvent e) {
incrementValue();
}
}
}
Side Recommendations:
While null layouts and setBounds() might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
Check out: The Use of Multiple JFrames, Good/Bad Practice?

How to implement layout?

I have a GUI program which includes JLabels and JButtons and basically I want a layout that would help me display them as follows:
Label1 Button1
Label2 Button2
Label3 Button3
.....
Is there a layout that would allow me to achieve the above result?
I have looked at this example but is too complex and was wondering if there is anything automated that I can use?

This is one of the few things for which I'd recommend (a utility method and) GroupLayout as seen in this answer.

You can use GridLayout. Documentation here.

This is just for simplicity, and for your question. GUI is really dependent on what you would like to do and is really a thing that can be hardly automated..., and i don't think you only want those 6 elements on your GUI, but theoretically this will do it:
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class GUITest {
private Box labelbox = new Box(BoxLayout.Y_AXIS);
//Y_AXIS means they are placed vertically in the box
private Box buttonbox = new Box(BoxLayout.Y_AXIS);
private JFrame frame = new JFrame();
private JPanel panel = new JPanel();
public void makeGUI1() {
for (int i = 1; i <= 3; i++) {
//if you want to save the references, you should make
//an ArrayList<JLabel> and add each of them to it
JLabel label = new JLabel("Label " + i);
labelbox.add(Box.createVerticalStrut(5));
//these are for giving the labels some extra space
//between them vertically to be in line with the buttons
labelbox.add(label);
labelbox.add(Box.createVerticalStrut(10)); //these are too
}
for (int i = 1; i <= 3; i++) {
//if you want to save the references, you should make
//an ArrayList<JButton> and add each of them to it
JButton button = new JButton("Button " + i);
buttonbox.add(button);
}
panel.add(labelbox, BorderLayout.EAST);
//you can find picture of each constant:
//http://download.java.net/jdk7/archive/b123/docs/api/java/awt/BorderLayout.html
panel.add(buttonbox, BorderLayout.WEST);
frame.add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
GUITest guitest = new GUITest();
guitest.makeGUI1();
}
});
}
}

You can also use obj.setBounds(LeftSpaceParameter,TopSpaceParameter) with which you can place the gui elements or objects at any position of your choice. You need to put the default layout to null
yet gridLayout is much easier. .

I'm attempting to create a small GUI application, but the contents of the JFrame are not showing on screen. How can I fix my code?

As of late I've been developing a (very) small GUI application in Java. I'm extremely new to Swing and Java in general, but up until now I have been able to get everything to work the way I want it to. However, after cleaning up my code, when I run the program nothing but the border of the window appears. What am I doing wrong and how can I fix my code? Thanks ahead of time!
For the sake of saving space I've made Pastebin links to all of my classes (besides Main).
Main Class
package me.n3rdfall.ezserver.main;
public class Main {
public static GUI g = new GUI();
public static void main(String[] args) {
g.showWindow(800, 500);
}
}
GUI Class
http://pastebin.com/gDMipdp1
ButtonListener Class
http://pastebin.com/4XXm70AD
EDIT: It appears that calling removeAll() directly on 'frame' actually removed essential things other than what I had added. By calling removeAll() on getContentPane(), the issue was resolved.

Quick hack: Remove the removeAll() functions.
public void homePage() {
// frame.removeAll();
// mainpanel.removeAll();
// topbar.removeAll();
I'm not sure what you're trying to achieve, but that will at least show some items. If I were you I would rebuild this GUI by extending JFrame. It will make your code a little easier to read.
I also think what you are trying to achieve with the buttons is to switch layouts, you can do this in an easier way by using CardLayout
Example (has nothing to do with your code, but to demonstrate):
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Example extends JFrame implements ActionListener {
private JButton leftButton;
private JButton rightButton;
private CardLayout cardLayout = new CardLayout();
JPanel cards = new JPanel(cardLayout);
final static String LEFTPANEL = "LEFTPANEL";
final static String RIGHTPANEL = "RIGHTPANEL";
JPanel card1;
JPanel card2;
public Example() {
JPanel topPanel = new JPanel();
addButtons(topPanel);
add(topPanel, BorderLayout.NORTH);
add(cards, BorderLayout.CENTER);
//Initiates the card panels
initCards();
setTitle("My Window");
setSize(300, 300);
setLocationRelativeTo(null);
setVisible(true);
}
private void initCards() {
card1 = new JPanel();
card2 = new JPanel();
card1.setBackground(Color.black);
card2.setBackground(Color.red);
cards.add(card1, LEFTPANEL);
cards.add(card2, RIGHTPANEL);
}
private void addButtons(Container con) {
leftButton = new JButton("Left Button");
leftButton.addActionListener(this);
rightButton = new JButton("Right Button");
rightButton.addActionListener(this);
con.add(leftButton, BorderLayout.WEST);
con.add(rightButton, BorderLayout.EAST);
}
#Override
public void actionPerformed(ActionEvent e) {
if(e.getSource().equals(leftButton)) {
//Change cardlayout
cardLayout.show(cards, LEFTPANEL);
} else if(e.getSource().equals(rightButton)) {
//Change cardlayout
cardLayout.show(cards, RIGHTPANEL);
}
}
public static void main(String[] args) {
new Example();
}
}

JCheckBox not showing (text appears, but without check box)

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class SideNotes {
public static JPanel panel = new JPanel();
private List<String> notes = new ArrayList<String>();
private static JButton add = new JButton("Add note");
public SideNotes() {
panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
panel.add(add);
loadNotes();
add.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
addNote();
}
});
}
public void addNote() {
String note = JOptionPane.showInputDialog("Enter note: ", null);
notes.add(note);
JLabel label = new JLabel(note);
panel.add(label);
panel.revalidate();
panel.repaint();
}
private void loadNotes() {
for (int i = 0; i < notes.size(); i++) {
JCheckBox jcb = new JCheckBox(notes.get(i), false);
panel.add(jcb);
panel.revalidate();
panel.repaint();
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setSize(200, 400);
panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
panel.add(add);
frame.add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
new SideNotes();
}
}
Why isn't my JCheckBox showing up? The text shows up but not the actual box. What's the deal?
I have edited my post to contain all of my code in case that helps solve the issue.
needmoretextneedmoretextneedmoretextneedmoretextneedmoretextneedmoretextneedmoretext

Possible reasons:
panel has not been added to GUI
panel has been added but for some reason is not visible.
panel is too small to show the child component. This can happen for instance if you set a component's size or preferredSize or if you place it in a FlowLayout-using container without thought.
panel uses null layout.
panel's layout manager is not one that easily accepts a new component -- think GroupLayout for this one.
There are other unspecified layout manager problems going on. Do you call pack() on your GUI? Do you use null layout or absolute positioning anywhere? Do you need to put panel in a JScrollPane?
Consider creating and posting an sscce for better help.
Edit
Your posted code doesn't ever add any JCheckBoxes to the JPanel, just JLabels. To prove this is so, click on the labels and you'll see that they don't respond to clicks.
Your code grossly over-uses static fields. Get rid of all static modifiers on all variables. They should all be instance variables. The only static anything in your code above should be the main method, and that's it. If this causes errors, then fix the errors, but not by making fields static.
Give your SideNotes class a method, getPanel() that returns the panel field.
Create a SideNotes instance in the beginning of your main method. Then call the above method on the instance to get the JPanel for the JFrame. i.e., frame.add(sideNotes.getPanel());.
Don't add JLabels to your GUI (I've no idea why you're doing this). Add JCheckBoxes in the actionPerformed method.

Every time you press the button, a new Note (JLabel) is added to the panel. But you never call loadNotes() after adding a new Note. So the JLabel is added but not its respective JCheckBox as intended.
Besides of this I'd suggest you make this change:
public void addNote() {
String note = JOptionPane.showInputDialog("Enter note: ", null);
if(notes != null) {
notes.add(note);
JLabel label = new JLabel(note);
panel.add(label);
panel.add(new JCheckBox(note, false));
panel.revalidate();
panel.repaint();
}
}
So you don't need to call loadNotes() and update the GUI just once.

JButtons re-enable themselves after being disabled

I have an array of JButtons which form a keypad interface. After six numbers are entered I want to disable the keypad so that no further numbers can be entered by the user.
I have written the code and the buttons do disable until the mouse hovers above any of them, then the buttons seem to re-enable themselves and run actionEvents added to them.
The full code is available here.
Possible things that I think are wrong.
There is some sort of MouseListener which is ignoring when I set button.setEnabled(false);
I haven't separated attributes from the buildGUI(); correctly, I only did this anyway so that the inner class could access them.
Possibly something to do with the gridLayout as disabling the buttons seems to work for my services JPanel buttons.

The problem lies in how you instantiated your Frame (CashMachine), not (directly) with its implementation.
You are calling buildGUI twice, one in the object's constructor, and then in the Driver class that instantiates the object. As a result, you are creating (and laying out) two sets of buttons.
When the buttons of the first set were eventually disabled, your mousing activity was revealing the second set of buttons. And a flaw in your ActionListener implementation can cause inputCount to take on values greater than 6, so buttons in the second set were not eventually disabled like those from the first set.
buildGUI should be private; it should be called in the CashMachine constructor, and not by your Driver class.
Conversely, in my opinion, CashMachine.setVisible should be called by the Driver class, and not by the CashMachine constructor.

The code works just fine I guess.

One possible source of confusion in your program is mixing number keys with control keys, Clear and Enter. Consider handling number keys separately with a single listener, as suggested in the NumberButton class shown below. Then you can handle the Clear and Enter buttons as desired. Also, using a List<NumberButton> makes the enable and disable loops easier.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
public class KeyPadPanel extends JPanel implements ActionListener {
private static final int MAX = 6;
private final List<NumberButton> numbers = new ArrayList<NumberButton>();
private final JTextArea text = new JTextArea(1, MAX);
private final JButton clear = new JButton("Clear");
private final JButton enter = new JButton("Enter");
public KeyPadPanel() {
super(new BorderLayout());
JPanel display = new JPanel();
text.setEditable(false);
display.add(text);
this.add(display, BorderLayout.NORTH);
JPanel pad = new JPanel(new GridLayout(4, 4));
for (int i = 0; i < 10; i++) {
NumberButton n = new NumberButton(i);
numbers.add(n);
if (i > 0) {
pad.add(n);
}
}
pad.add(clear);
pad.add(numbers.get(0));
pad.add(enter);
clear.addActionListener(this);
enter.addActionListener(this);
this.add(pad, BorderLayout.CENTER);
}
#Override
public void actionPerformed(ActionEvent e) {
text.setText("");
enableButtons();
}
private void enableButtons() {
for (NumberButton n : numbers) {
n.setEnabled(true);
}
}
private void disableButtons() {
for (NumberButton n : numbers) {
n.setEnabled(false);
}
}
private class NumberButton extends JButton implements ActionListener {
public NumberButton(int number) {
super(String.valueOf(number));
this.addActionListener(this);
}
#Override
public void actionPerformed(ActionEvent e) {
NumberButton b = (NumberButton) e.getSource();
if (text.getText().length() < MAX) {
text.append(b.getText());
}
if (text.getText().length() == MAX) {
disableButtons();
}
}
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new KeyPadPanel());
f.pack();
f.setVisible(true);
}
});
}
}

Examining the class files was helpful! The problem is in the Driver class:
the buildGUI() method is being called 2 times: once in the constructor of CashMachine and second in the main method after calling the constructor.
public static void main(String args[])
{
CashMachine cashmachine = new CashMachine();
cashmachine.buildGUI();
}
This way you end up with the double number of buttons, that is, a pair of buttons at each position. But only one of each is being disabled.
Just remove the call to buildGUI from main (or from the constructor).
(I would change buildGUI to private as it should not be called from outside the class...)