If Swing JComponent associated with JavaFX SwingComponent is obtained from JavaFX SwingComponent, the Swing JComponent screen coordinates (getLocationOnScreen) will be invalid. In the sample, we can see the SwingButton control on the scene. When clicking the "Redraw JComponent border" button, the screen coordinates of JButton, which is associated with SwingButton, are calculated:
     var jComponent = swingButton.getJButton();
     var locationOnScreenX = jComponent.getLocationOnScreen().getX();
     var locationOnScreenY = jComponent.getLocationOnScreen().getY();
     var width = jComponent.getWidth();
     var height = jComponent.getHeight();
 var jComponent = swingButton.getJButton();
     var locationOnScreenX = jComponent.getLocationOnScreen().getX();
     var locationOnScreenY = jComponent.getLocationOnScreen().getY();
     var width = jComponent.getWidth();
     var height = jComponent.getHeight();
The coordinates of the top left corner of this JButton component on the scene are also calculated:
     var locationOnSceneX = locationOnScreenX - scene.x - stage.x;
     var locationOnSceneY = locationOnScreenY - scene.y - stage.y;
After that, on the scene, a rectangle characterizing the JButton location within the JavaFX scene appears. The location of the rectangle does not correspond to the real location of the JButton component which is visually observed where the SwingButton component is. Moreover, the JButton coordinates change every time SwingButton is clicked (only make sure that you clicked the "Redraw JComponent border" button after that!). The screen coordinates returned by the objects of the lower hierarchy of the AWT\Swing components are invalid. For example, due to this fact, there is no way to determine the screen coordinates of the SwingList element or of the SwingComboBox element.


[JComponentLocationOnScreen.fx]

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.Node;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.scene.control.*;
import javafx.ext.swing.*;

var swingButton = SwingButton {translateY: 100; width: 150; text: "MySwingButton"; };
var rect = Rectangle {fill : Color.TRANSPARENT; stroke : Color.RED; };

Stage
{
title: "JComponent location on screen"
scene: Scene
{
content:
[
rect,
swingButton,
Button
{
translateY: 200;
translateX: 200;
text: "Redraw JComponent border"
action: function(): Void
{
var node = swingButton;
var scene = node.scene;
var stage = scene.stage;

var jComponent = swingButton.getJButton();
var locationOnScreenX = jComponent.getLocationOnScreen().getX();
var locationOnScreenY = jComponent.getLocationOnScreen().getY();
var width = jComponent.getWidth();
var height = jComponent.getHeight();

var locationOnSceneX = locationOnScreenX - scene.x - stage.x;
var locationOnSceneY = locationOnScreenY - scene.y - stage.y;

println("{jComponent.getClass().getName()} location on screen: {locationOnScreenX}, {locationOnScreenY}");
println("{jComponent.getClass().getName()} location on scene: {locationOnSceneX}, {locationOnSceneY}");
println("");

rect.translateX = locationOnSceneX;
rect.translateY = locationOnSceneY;
rect.width = width;
rect.height = height;
rect.toFront();
}
}
]
}
}