JavaFX Thread freeze

Question

I\'m currently working on a JavaFX project. On GUI initialization I want to read some infos out of a HTML document using Selenium and FirefoxDriver. Normally I would use a crawl

Answer 1

1. You look to be trying to make JavaFX calls directly from within a background thread, and while I know little about JavaFX, I do know that this is not allowed, that JavaFX calls must be made on the JavaFX Application thread. See Concurrency in JavaFX.
2. You're not even creating a background thread. You call st.run(); which runs st on the calling thread -- not what you want. You should be calling st.start()!
3. As a side note, you seem to be extending Thread where you really want to be implementing Runnable. Thus you really should be calling new Thread(myRunnable).start();

Answer 2

You are trying to update the UI from a different thread. The UI can only be updated from the UI thread. To achieve this, wrap the calls to update the progress:

Platform.runLater(() -> {main.getPbStart().setProgress(0.65);});

This will push the update of the UI into the UI thread.