FULL PRODUCT VERSION :
java version "1.8.0_121" Java(TM) SE Runtime Environment (build 1.8.0_121-b13) Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
10.0.14393

A DESCRIPTION OF THE PROBLEM :
ChoiceBox events are not emited when ChoiceBox is interacted with.
Instead ComboBox events is emited.
This is either implementation bug or documentation mismatch.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Create simple application:

public class StrangeBox extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        Pane pane = new Pane();
        ChoiceBox box = new ChoiceBox();
        box.getItems().addAll("Walk", "Run");

        pane.getChildren().addAll(box);

        Stream.of(ChoiceBox.ON_HIDDEN, ChoiceBox.ON_HIDING, ChoiceBox.ON_SHOWING, ChoiceBox.ON_SHOWN,
                ComboBox.ON_HIDDEN, ComboBox.ON_HIDING, ComboBox.ON_SHOWING, ComboBox.ON_SHOWN)
                .forEach(type -> box.addEventFilter(type, event -> System.out.println(type)));

        Scene scene = new Scene(pane);
        primaryStage.setScene(scene);
        primaryStage.setTitle("Choice box?");
        primaryStage.show();
    }
}

Run app fiddle with menu

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Any string in console starting with:
CHOICE_BOX_ON_
ACTUAL -
Only string starting with:
COMBO_BOX_BASE_ON_

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package ru.latuhin.choice;

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ChoiceBox;
import javafx.scene.control.ComboBox;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;

import java.util.stream.Stream;

public class StrangeBox extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        Pane pane = new Pane();
        ChoiceBox box = new ChoiceBox();
        box.getItems().addAll("Walk", "Run");

        pane.getChildren().addAll(box);

        Stream.of(ChoiceBox.ON_HIDDEN, ChoiceBox.ON_HIDING, ChoiceBox.ON_SHOWING, ChoiceBox.ON_SHOWN,
                ComboBox.ON_HIDDEN, ComboBox.ON_HIDING, ComboBox.ON_SHOWING, ComboBox.ON_SHOWN)
                .forEach(type -> box.addEventFilter(type, event -> System.out.println(type)));

        Scene scene = new Scene(pane);
        primaryStage.setScene(scene);
        primaryStage.setTitle("Choice box?");
        primaryStage.show();
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Use ComboBox instead of ChoiceBox, or reregister existing ChoiceBox events to the ComboBoxBase events.

SUPPORT :
YES