import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.stage.Stage;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import java.util.List;  
import javafx.beans.property.*;

 public class ComboBoxSetAllDifference13vs17App extends Application {

        /**
         * What does this do? <br />
         * - Creates a ComboBox backed by an ObservableList (ComboBox#setItems). The backing list is initialized with
         * three strings. <br />
         * - There is a property for a selected value, which is bidirectionally bound to the selected item of the
         * ComboBox. <br />
         * - When the property for the selected value is changed, the contents of the backing list/ComboBox are updated.
         * The selected value is contained in those contents. <br />
         * - We programmatically change the selected value twice. <br />
         * <p>
         * What to try? <br />
         * - Start the app <br />
         * - Observe the initial state after programmatic changes to the selected value:<br />
         * --- expected: "D" is selected in the ComboBox <br />
         * --- actual 13.0.1: "D" is selected in the ComboBox <br />
         * --- actual 17.0.1: null is selected in the ComboBox <br />
         * - Depending on certain small changes to the code (marked with NOTE 1 and NOTE 2), the behavior can be broken
         * also in 13.0.1, or made to start working in 17.0.1 . Those changes are very small (registration (order) of
         * listeners/bindings), but strongly affect the outcome. For which changes lead to which result, see "RESULTS"
         * below. <br />
         */
        @Override
        public void start(final Stage stage) throws Exception {

            final ObservableList<String> comboBoxItemsList = FXCollections.observableArrayList();

            final ObjectProperty<String> selectedValue = new SimpleObjectProperty<>();

            final List<String> stringsABC = List.of("A", "B", "C");
            final List<String> stringsDEF = List.of("D", "E", "F");

            final ComboBox<String> comboBox = new ComboBox<>();
            comboBox.setItems(comboBoxItemsList);

            // listeners only for debugging output
            initSelectionListeners(comboBox, "comboBoxWithSetItems");

            // NOTE 1a: If bidi binding is registered HERE (before adding listeners), it fails in fx 13.0.1 as well (selected value: null)
// comboBox.valueProperty().bindBidirectional(selectedValue);

            final BooleanProperty valueAdjusting = new SimpleBooleanProperty();
            selectedValue.addListener(obs -> {
                System.out.println("selectedValue property inval listener " + selectedValue.get());
            });
            selectedValue.addListener((obs, oldV, newV) -> {
                System.out.println(
                        "selectedValue property change listener newV=" + newV + " valueAdjusting="
                                + valueAdjusting.get());

                if (valueAdjusting.get() == true) {
                    // avoid infinite loop / stack overflow
                    System.out.println("ignoring value update during item update");
                } else {
                    if ("D".equals(newV) || "A".equals(newV)) {
                        valueAdjusting.set(true);
                        System.out.println("valueListener: triggering item update");
                        final List<String> newContent = "A".equals(newV) ? stringsABC : stringsDEF;
                        comboBoxItemsList.setAll(newContent);
                        System.out.println("valueListener: value after item update: " + comboBox.getValue());
                        System.out.println(
                                "valueListener: selection after item update: "
                                        + comboBox.getSelectionModel().getSelectedItem());
                        valueAdjusting.set(false);
                    }
                }
            });

            // NOTE 1b: If bidi binding is registered HERE, it works in fx 13.0.1 but fails in fx 17.0.1 as described felow
            comboBox.valueProperty().bindBidirectional(selectedValue);

            selectedValue.set("A");
            selectedValue.set("D");

            System.out.println("Selected value: " + selectedValue.get());

            // RESULTS :
            // fx 13.0.1 :
            // - with early bidi binding registration (NOTE 1a):
            // ---- with change listener on selectedIndex (NOTE 2): Selected value: D
            // ---- without change listener on selectedIndex: Selected value: null
            // - with late bidi binding registration (NOTE 1b):
            // ---- with change listener on selectedIndex (NOTE 2): Selected value: D
            // ---- without change listener on selectedIndex: Selected value: D
            //
            // fx 17.0.1 :
            // - with early bidi binding registration (NOTE 1a):
            // ---- with change listener on selectedIndex (NOTE 2): Selected value: D
            // ---- without change listener on selectedIndex: Selected value: null
            // - with late bidi binding registration (NOTE 1b):
            // ---- with change listener on selectedIndex (NOTE 2): Selected value: D
            // ---- without change listener on selectedIndex: Selected value: null
            //

            final StackPane mainRoot = new StackPane(new VBox(comboBox));
            final Scene scene = new Scene(mainRoot);

            stage.setTitle("ComboBoxSetAllDifference13vs17App");
            stage.setScene(scene);
            stage.sizeToScene();
            stage.show();
        }

        private static void initSelectionListeners(final ComboBox<?> comboBox, String string) {
            comboBox.valueProperty().addListener((obs, old, newV) -> {
                System.out.println(string + " -- " + "new selected value: " + newV);
            });

            comboBox.getSelectionModel().selectedItemProperty().addListener((obs, old, newItem) -> {
                System.out.println(string + " -- " + "new selected item: " + newItem);
            });

            // NOTE 2: when this listener is used, it also works in 17.0.1 !!!! -> property becomes valid because of change evaluation!
// comboBox.getSelectionModel().selectedIndexProperty().addListener((obs, old, newIndex) -> {
// System.out.println(string + " -- " + "new selected index: " + newIndex);
// });

            // invalidation listener does not make a difference!
            comboBox.getSelectionModel().selectedIndexProperty().addListener(obs -> {
                System.out.println(string + " -- " + "selected index invalidated");
            });
        }

        public static void main(final String[] args) {
            ComboBoxSetAllDifference13vs17App.launch(args);
        }

    }