Keyboard events

Pedro Duque Vieira pedro.duquevieira at
Mon Oct 7 07:57:11 PDT 2013

Hi Artem, Richard,

Thanks for your feedback! There's one more thing which further complicates
things and that I've forgot to mention. The chart is embedded in a swing
app, so doing as Artem suggests will not work: the scene will have to be
focused in order for it to receive keyboard events, right?

Thanks, best regards,

On Mon, Oct 7, 2013 at 3:53 PM, Richard Bair <richard.bair at>wrote:

> That being said, this seems like a very common use case, and I wonder if
> there is something more we could do (in the longer term, short term do as
> Artem suggests)
> > On Oct 7, 2013, at 3:56 AM, Artem Ananiev <artem.ananiev at>
> wrote:
> >
> >
> >> On 10/7/2013 2:40 AM, Pedro Duque Vieira wrote:
> >> Hi,
> >>
> >> I have the following use case:
> >> When the user presses shift and the mouse is hover the chart component
> the
> >> cursor must change to an open hand cursor signaling to the user that the
> >> chart is ready for a panning action.
> >> The problem is that for this to be possible I want the chart to be able
> to
> >> listen to keyboard events even when it doesn't have focus.
> >>
> >> I think this is not possible and I wonder why. Swing was the same, you
> >> could only listen to keyboard events if the control had focus. Is this a
> >> technical limitation? If there is no technical limitation I think it
> would
> >> be better to remove this restriction, I think it is limiting and the
> above
> >> scenario is a good use case to show that.
> >
> > This is not a technical limitation, it's just the way how it's supposed
> to work. All the key events are dispatched to the component in focus, this
> is what input focus is.
> >
> > Scenario you described should be easier to implement in FX than in
> Swing. In AWT/Swing, input events are dispatched to a single component,
> while FX is much more flexible. All the events are delivered to a Scene
> first, then dispatched to the focused component (or component under mouse,
> for mouse events), then bubbled up back to the Scene. What you need is to
> register a custom event filter for the scene and listen to all the key
> events.
> >
> > See Scene.addEventFilter() and Scene.addEventHandler() for details.
> >
> > Thanks,
> >
> > Artem
> >
> >> Thanks, best regards,
> >>

Pedro Duque Vieira

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