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Java Build a JavaFX Application Graphical User Interfaces Adding an Event Handler

Add an event handler for playButton

Here's my code:

playButton.setOnAction(new EventHandler<ActionEvent>(){
    public void handle(ActionEvent event) {

I think I may be close but still getting "Bummer!" error on the Event Handler line...

The code is similar to the code on these pages:



Any suggestions?

3 Answers

Craig Dennis
Craig Dennis
Treehouse Teacher

Hi james white !

Try using a lambda like I do in the video leading up to this code challenge: Adding Interactivity at 3:40.

Let me know if that helps!

Hi Craig, Thanks! I thought it was too simple to be a one-liner like:

playButton.setOnAction(evt -> System.out.println("Playing!"));

Hope this JavaFX course is only the first of a series.

Maybe the next one can be a game with some OpenGL involved.

Craig Dennis
Craig Dennis
Treehouse Teacher

Hey James, great idea! Want me to add that to the Java content roadmap Trello board?

Yes please!

I bookmarked that Trello board (which I hadn't known existed) as a sort of "pre-Roadmap" page.

I see there is a "Swing Data" course planned (which is interesting to see what they do with

dashboard-ing graphics-created-on-the-fly for the data),

but having worked with Swing and SWT over the years,

I think JavaFX has more momentum going forward (at least with me).

I've done some work to integrate/overlay JavaFX with JME (JMonkey 3) and hopefully that

kind of thing pops up in a Treehouse course at some point.

Overall I know there's more Java content coming, it's just so agonizingly slow

watching the roadmap (and content creation) pipeline,

but keep up the good work. james