Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.java.programmer > #34694

Re: JavaFX: Bindings, StringConverters, and ChangeListeners

Show all headers | View raw

Eric Douglas <e.d.programmer@gmail.com> writes:

Hi Eric,

>> To prevent the user from entering invalid input, the textProperty()
>> also has a ChangeListener that resets to the old value in case the
>> new value cannot be parsed to an Integer.
>
> Revert to old value?

Revert to old value in this case basically means the user types a key
and the value does not change.

> You don't want a user to be able to type something and see what they
> typed then change it on them.

Well, I think in this case it's not too bad, especially if the field
flashes when invalid input is entered.

> I don't know much about Java FX, I write Swing and have only needed
> the FX for the WebView, but for a numeric entry allowing only valid
> numbers I've used JTextField with a custom input filter.  The input
> filters process every character they try to add to or remove from the
> control before adding or removing it.

Yes, that's what I did in Swing, too.  And the FX ChangeListeners are
not too different.  At least, they are called on any key the user typed
into the text field.  My problem is more on the part on when the
binding's string-to-integer converter is invoked.  When entering text in
the middle or end, it'll be called after my listener (good!) but when
entering text at the front, it'll be called before my listener (bad!).

Bye,
Tassilo

Back to comp.lang.java.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

JavaFX: Bindings, StringConverters, and ChangeListeners Tassilo Horn <tsdh@gnu.org> - 2016-06-22 15:18 +0200
  Re: JavaFX: Bindings, StringConverters, and ChangeListeners Nigel Wade <nmw@ion.le.ac.uk> - 2016-06-22 15:22 +0100
    Re: JavaFX: Bindings, StringConverters, and ChangeListeners Tassilo Horn <tsdh@gnu.org> - 2016-06-23 08:39 +0200
      Re: JavaFX: Bindings, StringConverters, and ChangeListeners Martin Gregorie <martin@address-in-sig.invalid> - 2016-06-23 09:59 +0000
        Re: JavaFX: Bindings, StringConverters, and ChangeListeners Nigel Wade <nmw@ion.le.ac.uk> - 2016-06-23 12:19 +0100
      Re: JavaFX: Bindings, StringConverters, and ChangeListeners Nigel Wade <nmw@ion.le.ac.uk> - 2016-06-23 12:39 +0100
        Re: JavaFX: Bindings, StringConverters, and ChangeListeners Tassilo Horn <tsdh@gnu.org> - 2016-06-23 14:39 +0200
  Re: JavaFX: Bindings, StringConverters, and ChangeListeners Eric Douglas <e.d.programmer@gmail.com> - 2016-06-22 08:06 -0700
    Re: JavaFX: Bindings, StringConverters, and ChangeListeners Tassilo Horn <tsdh@gnu.org> - 2016-06-23 08:45 +0200
      Re: JavaFX: Bindings, StringConverters, and ChangeListeners Eric Douglas <e.d.programmer@gmail.com> - 2016-06-23 05:11 -0700
        Re: JavaFX: Bindings, StringConverters, and ChangeListeners Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-06-23 08:22 -0400
          Re: JavaFX: Bindings, StringConverters, and ChangeListeners Tassilo Horn <tsdh@gnu.org> - 2016-06-23 15:12 +0200
            Re: JavaFX: Bindings, StringConverters, and ChangeListeners Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-06-23 10:56 -0400

csiph-web