Скачать или смотреть How To Solve FAQs for JavaFX 11 or higher "Failed to automatically set up a JavaFX Platform"

In this tutorial, I will show you how to solve frequently asked questions (FAQs) when you run a JavaFX 11 or higher project using Apache NetBeans IDE 12, Scene Builder 11 on Windows 10 x64.

With the release of JDK 11 in 2018, Oracle has made JavaFX part of the OpenJDK under the OpenJFX project. It means that Oracle JDK 11 is no longer comes with JavaFX 11. To continue use JavaFX, we may choose to use current long-term version (JDK 8) through March 2025 or use OpenJFX 11 or higher after integrated into installed JDK.

It means that you have to do certain things by yourself.
1. Create a Java Application project for a JavaFX Application project. Then later on you may need to switch JavaSE project to JavaFX Application project type. The JavaFX Ant tasks of the current Apache NetBeans version (9.0 ~ 12.0) are not ready for JavaFX 11 or higher yet.

2. Add the JavaFX 14 library. You make sure your project is configured to run with JDK 11 or later, and you may add the JavaFX 14 library.

3. Use VM options to run the JavaFX project. You have to integrate JavaFX modules/jars into installed JDK 11 or higher. Then you have to use VM options to run the JavaFX project.

4. Run JavaFX application (e.g. FXMain.java) with Run File. Do NOT run you JavaFX application with Run Project, run JavaFX application (e.g. FXMain.java) with Run File.

The Installed directories are as following:

C:\Program Files\Java\jdk-14.0.2
C:\Program Files\Java\javafx-sdk-14.0.2.1
C:\Program Files\NetBeans-12.0
C:\Program Files\SceneBuilder

Problem
Failed to automatically set-up a JavaFX Platform. Please go to Platform Manager, create a non-default Java SE platform, then go to the JavaFX tab, enable JavaFX and fill in the paths to valid JavaFX SDK and JavaFX Runtime. Note: JavaFX SDK can be downloaded from JavaFX website.

Solution ,

To solve this issue, don't try to create a JavaFX project. You should reate a Java Application project. Then later on you may need to switch JavaSE project to JavaFX Application project type. The JavaFX Ant tasks of the current Apache NetBeans version are not ready for JavaFX 11 or higher yet.