JavaFX - TextArea not updating in real time

Question

I'm writing a piece of code that essentially iterates over a file containing a number of URLs, reads the corresponding HTMLs, runs a series of search operations on the HTMLs and the returns the results of these searches. I want these results to be displayed in a TextArea section of the UI too.

However, when I use the appendText method to display the search results, the TextArea is not updated immediately, not even at the end of the current iteration, it only updates once the whole loop has finished. This is a problem for users because there's no way to know if the application is stuck on an error or is just processing normally.

For comparison, I have included a System.out.println right after each appendText and the console does actually update in real time.

Am I doing anything wrong or is this the expected behavior of a TextArea? Is there anything I can do to make it more responsive?

Yes, this is expected behavior when you don't use background threading. — Hovercraft Full Of Eels, Sep 26 '17 at 16:19
Absolutely helpful, thanks a lot. I wasn't sure what to look for and thus wasn't able to find the question you referenced. — hmdrummer, Sep 26 '17 at 18:53
That's 90% of the battle -- finding the right search terms. Most GUI libraries have an event thread that the GUI runs on, and you want to avoid blocking that thread at all costs, lest the GUI become non-functioning. — Hovercraft Full Of Eels, Sep 26 '17 at 18:55

JavaFX - TextArea not updating in real time

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