Why don't GridPane, HBox, BorderPane, VBox, StackPane have Skins?

[Tom Eugelink]

The second a Pane does something more than layout its children, but renders something (like TabPane does), I agree. Pure layout does not need a skin.

On 26-4-2019 15:13, Alex Sviridov wrote:
> I am studying JavaFX API and can't understand why GridPane, HBox, BorderPane, VBox, StackPane don't have Skins. According to Skin API doc:
>> Base class for defining the visual representation of user interface controls by defining a scene graph of nodes to represent the skin. A user interface control is abstracted behind the Skinnable interface.
> Why do JavaFX developers use skins only for controls, but not for the above panes? I am asking, because these panes also have visual representation. For example, we can set color, they have children which can be placed somehow differently etc. Could anyone explain?