# JavaFX in version 4

**URL:** <https://discourse.processing.org/t/javafx-in-version-4/38632>\
**Category:** Development\
**Created:** [September 3, 2022, 3:41pm UTC](https://discourse.processing.org/t/javafx-in-version-4/38632 "2022-09-03T15:41:09Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![svan](https://avatars.discourse-cdn.com/v4/letter/s/82dd89/32.png) [@svan](https://discourse.processing.org/u/svan)\
**Post date:** [September 3, 2022, 3:41pm UTC](https://discourse.processing.org/t/javafx-in-version-4/38632/1 "2022-09-03T15:41:09Z")

</div>

I am able to add Text, Rectangle, Circle to a JavaFX window in version 4.0.1, but fail when it comes to adding a Button control. Error msg is shown below. Does anyone know how to fix this?

```auto
import processing.javafx.*; // Add this for Processing 4:

import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

void setup() {  
  size(1, 1, FX2D);
  surface.setVisible(false); // Don't show default Processing window
 
  Stage stage = new Stage();
  stage.setTitle("Button demo");
  Button btn = new Button("button");
  StackPane pane = new StackPane();
  pane.getChildren().add(btn);
  Scene scene = new Scene(pane, 400, 400);
  stage.setScene(scene);
  stage.show();
  
}

void draw() {
}

```

 ![javafx_err](https://canada1.discourse-cdn.com/flex036/uploads/processingfoundation1/original/3X/9/0/908f82b0b7592f968af7a5d9d06ded931eeef0e0.png)