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Setting Button command javafx

I've been using JFrame to learn graphics and test my code because I know it much better. Now I want to update to Javafx. I have this JListener class that handles all the buttons for my JFrame. Is it possible to still use this class with Javafx? If so how?
For example, with JFrame I could use Button.setActionCommand("command"); and when the button was pressed it would run this with the actionListener, can I do this same thing with javafx?
package src.com.Kingdom;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.util.Timer;
import java.util.TimerTask;
import java.util.Scanner;
import java.net.*;
public class JListener implements ActionListener
{
private boolean registered = false;
registerClient register;
loginClient login;
static GUIs gui = new GUIs();
#Override
public void actionPerformed(ActionEvent e) {
switch(e.getActionCommand()) {
case("login"):
login = new loginClient(gui.getUsername(), gui.getPassword());
System.out.println("Login");
break;
case("exit"):
System.out.println("exit");
break;
case("register"):
System.out.println("register");
gui.getFrame().dispose();
gui.createRegisterGui();
break;
case("registerperson"):
if(gui.checkRegister()) {
if(hasInternet()) {
if(!(registered)) {
registered = true;
try {
register =
new registerClient(gui.getUsername(), gui.getPassword(), gui.getEmail(), gui.getAge());
} catch(Exception ex) {
GUIs.showError(ex.getMessage());
}
if(!(register.isRegistered())) {
gui.createLoginGui();
}
new Timer().schedule(new TimerTask() {
public void run() {
registered = false;
}
},1000*1);
}
} else {
GUIs.showError("No Internet! Please connect to internet to connect!");
}
} else {
GUIs.showError("Problem with registration format");
}
break;
}
}
}

It is technically possible to integrate JavaFX and Swing. Oracle provide a tutorial on this. I don't recommend integrating the two unless you really need to (which you probably don't in this case). Note that the level of integration possible is just embedding Swing Components into JavaFX nodes (or vice versa). You cannot directly use a Swing listener to take action on a JavaFX button press.
Instead, I recommend that you write your code native to a single library, either JavaFX or Swing.
For your example code. The JavaFX equivalent for handling button actions is:
button.setOnAction(EventHandler<ActionEvent>)
How would I set the String for the action command? Is this possible? Or do I have to do it a different way?
You wouldn't, it's not necessary.
I don't code Swing, so I'm not familiar with the Swing ActionEvent. From looking at your code, your listener seems to be providing a single point for handling multiple action events which originate from different sources, then acting on them.
For JavaFX, just define separate event handlers for each source rather than using switches, then you don't need to pass a string to the action command because it is clear what action is to be taken based upon the context.
For instance:
loginButton.setOnAction(event -> { /** handle login **/});
exitButton.setOnAction(event -> { /** handle exit **/});
If you have multiple ways to trigger the actions, for instance an exit could be triggered by both a menu item and a button, then you can define a variable for the action handler and reuse that for each instance, for instance:
EventHandler<ActionEvent> exitHandler = event -> { /** handle exit **/ };
exitButton.setOnAction(exitHandler);
exitMenuItem.setOnAction(exitHandler);

Workaround for bug_id=4806603 regarding getBounds() and setBounds() on Linux?

On the Linux platform, Frame::getBounds and Frame::setBounds do not work consistently. This has already been reported in 2003(!), see here:
http://bugs.java.com/bugdatabase/view_bug.do?bug_id=4806603
For convenience, I have simplified the stated code that results in a bug and paste it as:
import java.awt.Button;
import java.awt.Frame;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
/** Demonstrates a bug in the java.awt.Frame.getBounds() method.
* #author Mirko Raner, PTSC
* #version 1.0 (2003-01-22) **/
public class GetBoundsBug extends Frame implements ActionListener {
public static void main(String[] arg) {
GetBoundsBug frame = new GetBoundsBug();
Button button = new Button("Click here!");
button.addActionListener(frame);
frame.add(button);
frame.setSize(300, 300);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent event) {
Rectangle bounds = getBounds();
bounds.y--;
setBounds(bounds);
bounds.y++;
setBounds(bounds);
}
}
Unexpected behavior: Upon clicking the button the window is shifted slightly below! (On my system by 28 pixels each click.)
Here is a screen recording: https://youtu.be/4qOf99LJOf8
This behavior has been around for 13+ years, so probably there won't be any change from the official side.
Does anybody have a workaround for this bug? Specifically, I would like to store and restore the window/frame/dialog at the previous location reliably on all platforms.
PS: My java installation is jdk1.8.0_102 for amd64 by Oracle on Ubuntu 16 Linux. Since I recently migrated from Windows to Ubuntu, I know that on Windows, the code above works as expected.
The adaptation to Swing using SwingWorker produces the same effect:
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingWorker;
public class GetBoundsBug extends JFrame implements ActionListener {
public static void main(String[] arg) {
GetBoundsBug myJFrame = new GetBoundsBug();
JButton myJButton = new JButton("Click here!");
myJButton.addActionListener(myJFrame);
myJFrame.setContentPane(myJButton);
myJFrame.setSize(300, 300);
myJFrame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent event) {
SwingWorker<Void, Void> mySwingWorker = new SwingWorker<Void, Void>() {
#Override
public Void doInBackground() {
Rectangle myRectangle = getBounds();
myRectangle.y--;
setBounds(myRectangle);
myRectangle.y++;
setBounds(myRectangle);
return null;
}
};
mySwingWorker.execute();
}
}

Well, in the original bug database entry this is marked as "Won't fix" and explained as a quirk in the window manager, rather than the JDK.
What window manager are you using?

Just an additional note. I noticed that your code failed to do very much on the Event Dispatch Thread. All of Java's drawing APIs are single threaded by design, meaning that your application should not be expected to work correctly unless you dispatch GUI updates to the Event Dispatch Thread.
This means you need to (in your main) create a new Runnable that when evaluated will present your widgets, and submit that to the EDT.
Also, your action listener updates the component state within the action, bypassing the repaint request and ignoring the typical safeties required to ensure dispatch to the EDT.
In both of these ways, you code is not valid GUI code in a Java environment, and the bug that you identify may have nothing to do with your behavior, as your program is violating the GUI toolkit design before you even know if the bug impacts it.
Also, awt only wraps components. If the components lie, then the lie trickles into Java. Not much can be done about that (but I no longer think it's the primary thing to worry about). If you don't like that, use Swing, which is a much more sane / stable environment.

return a variable value to main on button click

I want that main should print hello (in a pop up dialogue box) everytime the button is clicked. So I designed the following program but it doesn't seem to work. The program compiles and executes just fine but when I click the button, I don't see the any dialogue box popping up. I have put in place the getter and setter of the boolean variable (button_clicked) whose value is being tested in the main() block.
Please help if you know..
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
class abc extends JFrame implements ActionListener{
boolean button_clicked = false;
JButton b1;
abc(){
this.setSize (400, 400);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.createUI();
}
void createUI(){
this.setLayout(null);
b1 = new JButton("x");
b1.setSize(110,30);
b1.setLocation(10,210);
this.add(b1);
b1.addActionListener(this);
}
public boolean isButton_clicked() {
return button_clicked;
}
public void setButton_clicked(boolean button_clicked) {
this.button_clicked = button_clicked;
}
public void actionPerformed(ActionEvent arg0) {
button_clicked = true;
//I don't want to print the dialogue box from here..
//I want to keep everything under main()'s control.
}
}
public class tempMain extends JFrame {
public static void main(String[] args) {
abc temp = new abc();
temp.setVisible(true);
while(true){
if(temp.isButton_clicked())
JOptionPane.showMessageDialog(null, "Hello");
}
}
}

Move the JOptionPane.showMessageDialog() call under the actionPerformed() method and delete the while() thing under the main method.

As has already been pointed out by a number of people, you approach and design are flawed. I won't go into further as it has already been dealt with, but as a suggestion you could try...
abc temp = new abc();
temp.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
JOptionPane.showMessageDialog(null, "Look Ma, I'm in Main...");
}
});
temp.setVisible(true);
And in your abc class...
class abc JFrame implements {
// build your class as normal
public void addActionListener(ActionListener listener) {
b1.addActionListener(listener);
}
}

You might want to read about "How to Write an Action Listener" to help you implement an ActionListner in your code.
The basic idea for your code would be to:
Declare an event handler class
Register an instance of the event handler class as a listener with your JButton
Include code that implements the methods in listener interface. In your case, you would over-ride actionPerformed() and write your logic over there to show a dialog box. "How to Make Dialogs" would be another useful tutorial for you.

As #Quinman pointed out, your code design is really flawed. I understand that you do not want to put the JOptionPane under the actionperformed method for some personal reason which I don't understand. Based on that premise, I think that the best solution would be to create a callback, that is, make your JFrame know the main class and call it when the button is clicked.
It is possible to make this mechanism independent of the main class. Please check the Observer design pattern in order to understand how to do that.
Your code also has another flaw - when the button is clicked I get infinite Hello messages. In order to avoid that, you should set the button_clicked variable to false. I only mention that as a general tip, for in truth you really should get rid of the busy wait that your while is causing.

You may be looking for a modeless dialog. In this example, the main panel, named Observer, listens to an ObservedPanel in a dialog. By using a PropertyChangeListener, any changes made to the dialog are immediately reflected in the main panel.

Judging from the comments you provided, you want to reuse your abc class (which has a very poor name and does not comply to the Java naming standards) for several different purposes, so you do not want to include the code which is executed when you press the button in the abc class.
There are multiple solutions for this (where the first is my preferred one)
Pass an Action in the constructor of your abc class and couple that Action to the JButton. This way the class which constructs the abc instance is responsible for the behavior when the button is pressed
make abc abstract and let your ActionListener call that abstract method. You can then make concrete implementations of this class each time you want different behavior.
Further notes on your code:
get rid of that while( true ) loop
get rid of the null layout and use a LayoutManager instead
Swing components should be created and accessed on the Event Dispatch Thread. Consult the Concurrency in Swing tutorial for more information

Capturing global key presses with java.awt.Toolkit

I found the method addAWTKeyListener in the class Toolkit, but I can't get it to work properly, whether or not the window has focus. My code is as follows:
import java.awt.AWTEvent;
import java.awt.Toolkit;
import java.awt.event.AWTEventListener;
import java.awt.event.KeyEvent;
public class KeyTest {
public static void main(String[] args){
Thread t = new Thread(){
#Override
public void run() {
System.out.println("STARTING");
Toolkit kit = Toolkit.getDefaultToolkit();
kit.addAWTEventListener(new AWTEventListener(){
#Override
public void eventDispatched(AWTEvent event) {
System.out.println("EVENT");
if(event instanceof KeyEvent){
KeyEvent kEvent = (KeyEvent) event;
System.out.println(kEvent.getKeyCode());
}
}
}, AWTEvent.KEY_EVENT_MASK);
while(true);
}
};
t.start();
}
}
Is there something I'm doing wrong? I get to the point that STARTING prints and there are no errors. The even is simply not called.

I may be wrong as I'm certainly not an expert, but as far as I know what you're trying to do isn't possible in Java.
Are you trying to capture a key click using a Java program, but without creating a window? Part of Java's security, and this is what I may be wrong on, is that it can only listen to events inside Java windows created by that particular Java program.
So if you were trying to make something key-logger-esque that runs in the background and captured a key press, it wouldn't be able to do that.
I wish I could give you a more concrete answer but I hope this helped.

Just a guess, but you your sample doesn't have any AWT windows in it, so I'm guessing that is why the event never gets fired.
When you say "whether or not the window has focus" does your real app have windows that you have chopped out, or are you talking about a java console window or similar?

Attach to Window events from JPanel

I'm trying to listen for a window close event on the parent JFrame of a JPanel. In the WindowClosing event I'd like to de-register a listener to a different component.
Unfortunately the only code I can gaurantee to have run is the constructor for the panel. What this means is that the panel itself doesn't have an ancestor window yet, so simply calling SwingUtilities.getWindowAncestor doesn't work. So what I do is register a hierarchy listener, and in the hierarchyChanged event look for SHOWING_CHANGED event. When that even fires, now I can look for the window ancestor of the panel.
So basically I have the following:
class ShapeControlPanel extends JPanel{
public ShapeControlPanel(){
final ShapeControlPanel me = this;
me.addHierarchyListener(new HierarchyListener() {
#Override
public void hierarchyChanged(HierarchyEvent e) {
if((e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED) == HierarchyEvent.SHOWING_CHANGED){
SwingUtilities.getWindowAncestor(me).addWindowListener(new WindowListener() {
/* Snipped some empty handlers */
#Override
public void windowClosing(WindowEvent e) {
/* Finally get to remove the handler. */
me.getApparent().removeLocationSelectionListener(me.GUID(), me);
}
});
}
}
});
}
}
Is this sane? Is there a more reasonable way of getting a handle on the frame closing event?

It's not the ugliest thing I've seen (I wouldn't even say it's all that bad), but you have to ask yourself: why does your panel really need to know when the window is closed? It seems to be an odd coupling that would best be removed.
I don't know enough about your context and what you are truly trying to accomplish to suggest an alternative right now. But if a panel needs to know about the container in which it resides, there is probably some bad design with harmful coupling.