JavaFX Observable Value

Question

I am beginning to cover GUIs using JavaFX on my own and I was just curious as to how instances of ObservableValue can "monitor" a particular value for changes. It is an important concept for property binding but my book doesn't really explain how they accomplish this and I'm just curious.

Thanks.

score 5 · Answer 1 · answered Jun 18 '16 at 17:02

5

There is no magic behind the Observable types. Actually, it's really simple:

The only way to change the value of a *Property class from the outside is by it's setter method, which just triggers the listener.

answered Jun 18 '16 at 17:02

vsakos

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score 4 · Answer 2 · edited May 23 '17 at 12:33

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It is an observer pattern you can read up on the observer design. If you want to find the specifics of how it is implemented in JavaFX, then study the JavaFX source, in particular the property source, a key class involved is the ExpressionHelper.

edited May 23 '17 at 12:33

Community

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answered Jun 18 '16 at 21:39

jewelsea

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JavaFX Observable Value

2 Answers2