add calculating methods to bind

[Tom Eugelink]

I feel the standard binding should offer an easy hook option

heightProperty().multiply(3.4).calc( value -> { snap(vallue); } ).add(5.0)


On 2014-5-21 22:00, Tomas Mikula wrote:
> Just a side note, you could use
>
>      EasyBind.map(heightProperty(), value ->
> NodeUtil.snapXY(value.doubleValue() * 0.2));
>
> instead of
>
>      snap(heightProperty().multiply(0.2))
>
> and you don't need your custom DoubleBinding implementation. But note
> that it returns Binding<Double>, not DoubleBinding.
>
> EasyBind is at http://www.fxmisc.org/easybind/
>
> Tomas
>
> On Wed, May 21, 2014 at 9:47 PM, Tomas Mikula <tomas.mikula at gmail.com> wrote:
>> Yeah, and you could also eliminate "Observable... dependencies" from
>> snap's signature, since now you are not using them to invalidate your
>> binding.
>>
>> On Wed, May 21, 2014 at 9:36 PM, Tom Eugelink <tbee at tbee.org> wrote:
>>> Found it! Slightly different DoubleBinding was required (copied it from
>>> negate).
>>>
>>>      private DoubleBinding snap(final ObservableNumberValue value, final
>>> Observable... dependencies) {
>>>          return new DoubleBinding() {
>>>              {
>>>                  super.bind(value);
>>>              }
>>>
>>>              @Override
>>>              public void dispose() {
>>>                  super.unbind(value);
>>>              }
>>>
>>>              @Override
>>>              protected double computeValue() {
>>>                  return NodeUtil.snapXY(value.doubleValue());
>>>
>>>              }
>>>
>>>              @Override
>>>              public ObservableList<?> getDependencies() {
>>>                  return FXCollections.singletonObservableList(value);
>>>              }
>>>          };
>>>
>>>      }
>>>
>>>
>>>
>>> On 2014-5-21 21:34, Tomas Mikula wrote:
>>>> Hi Tom,
>>>>
>>>> it seems to me that in your custom DoubleBinding implementation
>>>> `other` is not its dependency, thus it does not react to it's
>>>> invalidations.
>>>>
>>>> Tomas
>>>>
>>>> On Wed, May 21, 2014 at 9:25 PM, Tom Eugelink <tbee at tbee.org> wrote:
>>>>> I came up with this:
>>>>>
>>>>> startXProperty().bind( *snap(*heightProperty().multiply(0.2)) )
>>>>>
>>>>>
>>>>> And then:
>>>>>
>>>>>       private DoubleBinding snap(final ObservableNumberValue other, final
>>>>> Observable... dependencies) {
>>>>>           return new DoubleBinding() {
>>>>>               {
>>>>>                   super.bind(dependencies);
>>>>>               }
>>>>>
>>>>>               @Override
>>>>>               public void dispose() {
>>>>>                   super.unbind(dependencies);
>>>>>               }
>>>>>
>>>>>               @Override
>>>>>               protected double computeValue() {
>>>>>                   return NodeUtil.snap(other.doubleValue());
>>>>>               }
>>>>>
>>>>>               @Override
>>>>>               public ObservableList<?> getDependencies() {
>>>>>                   return new
>>>>> ImmutableObservableList<Observable>(dependencies);
>>>>>               }
>>>>>           };
>>>>>       }
>>>>>
>>>>> But that always returns 0... I feel this should have worked.
>>>>>
>>>>> Tom
>>>
>>>