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JavaFX ScrollPane receiving ScrollEvents on mouse enter

I have a JavaFX application with a ScrollPane that handles resizing of nodes upon scrollEvents. However when the JavaFX stage (or Window) is not focused, I get an odd behaviour that I think might be a JFX bug, though wondering if anyone has encountered or managed to resolve it.
To replicate the issue, if you lose focus on the JavaFX window and perform some scrolling using the mouse-wheel on another window (eg your browser), and then relatively quickly move your mouse back to re-enter the JavaFX window (without clicking, scrolling or focusing upon the JavaFX window) the JavaFX window receives a bunch of scrollEvents despite no mouse-wheel action being performed.
I'm wondering if anyone has encountered this and worked out a way to somehow filter these odd scrollEvents out as it results in some strange zooming action that is unexpected given the lack of mouse-wheel scrolling!
I'm using Java & JavaFX 17 (OpenJFX), see below sample application that demonstrates, thanks!
public class ScrollEventIssueApplication extends Application {
#Override
public void start(Stage primaryStage) {
BorderPane borderPane = new BorderPane ();
borderPane .setPrefWidth(600);
borderPane .setPrefHeight(600);
Pane content = new Pane();
content.setPrefWidth(1000);
content.setPrefHeight(1800);
ScrollPane scrollPane = new ScrollPane(content);
scrollPane.setPrefWidth(700);
scrollPane.setPrefHeight(700);
content.setOnScroll(event -> {
System.out.println("Scroll event received: " + event.getDeltaY());
});
borderPane.setCenter(scrollPane);
Scene scene = new Scene(borderPane, 1800, 900);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}

It appears that this may be a platform-dependent feature of the installed pointing device and driver. I could occasionally reproduce the effect on Mac OS X 12 with JavaFX 17, but only when I also accidentally raked an errant finger or two across the mouse's multi-touch surface.
For reference, I tested the following simpler variation. Note code to enumerate the OS and Java version numbers, as well as changes to the viewport dimensions in order to show the scroll bars when set to AS_NEEDED by default.
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
/** #see https://stackoverflow.com/q/72485336/230513 */
public class ScrollTest extends Application {
private static final double W = 640;
private static final double H = 480;
#Override
public void start(Stage stage) {
Pane content = new StackPane();
content.getChildren().addAll(new Rectangle(W, H, Color.BLUE),
new Circle(Math.min(W, H) / 2, Color.LIGHTBLUE));
ScrollPane scrollPane = new ScrollPane(content);
scrollPane.setPrefViewportWidth(2 * W / 3);
scrollPane.setPrefViewportHeight(2 * H / 3);
content.setOnScroll(event -> System.out.println(
"dx dy: " + event.getDeltaX() + " " + event.getDeltaY()));
stage.setScene(new Scene(scrollPane));
stage.show();
}
public static void main(String[] args) {
System.out.println(System.getProperty("os.name")
+ " v" + System.getProperty("os.version")
+ "; Java v" + System.getProperty("java.version")
+ "; JavaFX v" + System.getProperty("javafx.runtime.version"));
launch(args);
}
}

I realised the issue was the mouse I was using (a Logitech MX Vertical Advanced Ergonomic) had a "smooth scrolling" option on the mouse wheel that meant to it would "continue" some small scroll events after the mouse wheel had stopped scrolling which were causing this issue. Turning off that option in the Logitech Options application resolved the issue.

GUI not appearing with eclipse JavaFX

I'm currently stuck with JavaFX on eclipse.
My program runs, compiles, and the java application will open as if the program is being executed correctly, however the actual GUI and app won't appear.
The main difference between my problem and the problem of many other people is:
I have the stage.show(); method being called and
the program works as intended on textEdit (Implying that this problem is due to eclipse)
In case you need it, here is the program
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class HelloFX extends Application
{
#Override
public void start(Stage stage)
{
String javaVersion = System.getProperty("java.version");
String javafxVersion = System.getProperty("javafx.version");
Label l = new Label("Hello, JavaFX " + javafxVersion + ", running on Java " + javaVersion + ".");
Scene scene = new Scene(new StackPane(l), 640, 480);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args)
{
launch();
}
}
Any ideas? I am thoroughly lost.
P.S. I am extremely new to programming - Java is my only language as of right now and this is my first time on stack overflow, so expect a dumb mistake to have been made

Trying to select programatically in JavaFX is not working

I am in the process of teaching myself JavaFX. Coming from the Swing world there are a lot of similarities between the 2. Especially event processing. Part of my process is to try and mimic an existing application as closely as possible. One of the things I am doing is creating a dialog that will allow the user to select a font to use. There is a text field for them to type in the font name and a list where they can scroll and select one. When they start typing the list will automatically scroll to through the list to start matching what the user is typing. I am also trying to populate the text field with the currently matched font name and then highlight the portion that the user has not typed yet so they can continue to type until the correct match is found.
For example if the user types the letter 't' on Windows the first font found is Tahoma. So the text field will be set to Tahoma and the carat will be positioned right after the 'T' and the 'ahoma' will be highlighted. What happens instead is that the field is populated with Tahoma and the carat is positioned at the end and nothing is highlighted. So it is like it is ignoring the 2 lines of code for positioning and highlighting or the event processor is causing my calls to JavaFX libraries to be run out of order.
I think this may be a bug with JavaFX but it could also be my misunderstanding of the event system. Please let me know which one and why.
Here is a complete sample code showing the problem. Just start typing in the text field to try it out.
package test;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.layout.BorderPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;
public class TestTyping extends Application {
ChangeListener<String> textChange;
#Override
public void start(Stage primaryStage) throws Exception {
BorderPane root = new BorderPane();
TextField text = new TextField();
root.setTop(text);
Scene scene = new Scene(root);
primaryStage.setScene(scene);
primaryStage.show();
textChange = (observable, oldValue, newValue) -> {
text.textProperty().removeListener(textChange);
for (String family : Font.getFamilies()) {
if (family.equalsIgnoreCase(newValue) || family.toLowerCase().startsWith(newValue.toLowerCase())) {
text.setText(family);
text.positionCaret(newValue.length());
text.selectEnd();
break;
}
}
text.textProperty().addListener(textChange);
};
text.textProperty().addListener(textChange);
}
public static void main(String... args) {
launch(args);
}
}

Wrap caret position and select end into Platform.runLater. The problem is in events order. I don't know correct details about this issue so I will not provide you a detailed answer, only solution.
Platform.runLater(()-> {
text.positionCaret(newValue.length());
text.selectEnd();
});

Here's an alternative approach entirely, which uses a TextFormatter to modify changes to the text. The advantage here is that it doesn't rely on the "timing" of various property changes with respect to event handling, which is not documented and thus could possibly change in later JavaFX versions. It also avoids the slightly ugly "remove the listener and add it back" idiom.
import java.util.function.UnaryOperator;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.control.TextFormatter;
import javafx.scene.control.TextFormatter.Change;
import javafx.scene.layout.BorderPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;
public class TestTyping extends Application {
ChangeListener<String> textChange;
#Override
public void start(Stage primaryStage) throws Exception {
BorderPane root = new BorderPane();
TextField text = new TextField();
root.setTop(text);
Scene scene = new Scene(root);
primaryStage.setScene(scene);
primaryStage.show();
UnaryOperator<Change> filter = c -> {
// for delete, move the caret, or change selection, don't modify anything...
if (c.getText().isEmpty()) {
return c ;
}
for (String family : Font.getFamilies()) {
if (family.toLowerCase().startsWith(c.getControlNewText().toLowerCase())) {
c.setText(family.substring(c.getRangeStart(), family.length()));
c.setAnchor(c.getControlNewText().length());
break ;
}
}
return c ;
};
text.setTextFormatter(new TextFormatter<String>(filter));
}
public static void main(String... args) {
launch(args);
}
}

JavaFX and Swing performance issues

We have been having perpetual performance issues when running JavaFX inside a JFXPanel in Swing based applications.
This seems to only be a problem when running on JDK1.7, because whenever it is possible to run JDK1.8 this works perfectly without changing any code.
The symptoms are that the application seems to render fonts in a fuzzy way and also the performance is terrible (multiple seconds to respond to keypress when typing in a TextField).
We are observing the correct rules about EDT, AWT and Platform threads, so I doubt that this can be the issue.
We are stuck having to support JDK1.7 because this is a plug-in for NetBeans which some users will be running on JDK1.7 for various good reasons and we cannot force them to upgrade.
EDIT: Here is a MCVE which recreates the problem
package javaapplication3;
import javafx.application.Platform;
import javafx.embed.swing.JFXPanel;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
public class Test {
private static void initAndShowGUI() {
// This method is invoked on the EDT thread
JFrame frame = new JFrame("Swing and JavaFX");
final JFXPanel fxPanel = new JFXPanel();
frame.add(fxPanel);
frame.setSize(300, 200);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Platform.runLater(new Runnable() {
#Override
public void run() {
initFX(fxPanel);
}
});
}
private static void initFX(JFXPanel fxPanel) {
// This method is invoked on the JavaFX thread
Scene scene = createScene();
fxPanel.setScene(scene);
}
private static Scene createScene() {
Group root = new Group();
Scene scene = new Scene(root, Color.ALICEBLUE);
TextField text = new TextField();
Label label = new Label();
VBox box = new VBox();
label.setText("This is a test label");
box.getChildren().add(label);
box.getChildren().add(text);
root.getChildren().add(box);
return (scene);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
initAndShowGUI();
}
});
}
}
The tests we are performing have very simple javafx with e.g. only an AnchorPane with a TextField on it and absolutely no code behind it, and just typing in the TextField is painfully slow.
Behavior looks very much like lock contention between the Swing and JavaFX threads, but it does not seem like we can find any explanation or solution.

This is not the answer that you are looking for, but since we have the same problem with Java 7 support, the answer is that Java 7 has reached its end of life:
July 2015: Updates for Java 7 are no longer available to the public.
Oracle offers updates to Java 7 only for customers who have purchased
Java support or have Oracle products that require Java 7.
https://www.java.com/en/download/faq/java_7.xml
There are no "good reasons" if problem solving is as easy as using a different java version. You don't break things by upgrading to Java 8.

JavaFX primaryStage remove windows borders? [duplicate]

This question already has an answer here:
JavaFX: Undecorated Window
(1 answer)
Closed 8 years ago.
I am making JavaFX destop application. I want to remove the default windows border and also I want to customize the 3 standard icons of minimize , maximize and close.
The original motivation of this kind of looks or customization is new Kaspersky 2012 User Interface.... I want to design something like that... :)

This example might be a good starting point. All window decoration is removed. A class extending HBox can be used to place custom buttons for standard window operations.
package javafxdemo;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ToolBar;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
import javafx.stage.StageStyle;
public class JavaDemo extends Application {
public static void main(String[] args) {
launch(args);
}
class WindowButtons extends HBox {
public WindowButtons() {
Button closeBtn = new Button("X");
closeBtn.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent actionEvent) {
Platform.exit();
}
});
this.getChildren().add(closeBtn);
}
}
#Override
public void start(Stage primaryStage) {
//remove window decoration
primaryStage.initStyle(StageStyle.UNDECORATED);
BorderPane borderPane = new BorderPane();
borderPane.setStyle("-fx-background-color: green;");
ToolBar toolBar = new ToolBar();
int height = 25;
toolBar.setPrefHeight(height);
toolBar.setMinHeight(height);
toolBar.setMaxHeight(height);
toolBar.getItems().add(new WindowButtons());
borderPane.setTop(toolBar);
primaryStage.setScene(new Scene(borderPane, 300, 250));
primaryStage.show();
}
}
You can also download the JavaFX Samples where you can find many more useful examples.