JEP 253: Prepare JavaFX UI Controls & CSS APIs for Modularization

[Tomas Mikula]

Hi Robert,

> The Behaviors contain logic at the moment, various functions that are used
> by the skin or the behavior itself (for example the selectNextTab() function
> in the TabPaneBehavior).

In my view, such code should be refactored to not have any
back-reference from skin to behavior. As a result, it will be
impossible for the skin to directly call methods of behavior.

Tomas