import javafx.application.Application;
import javafx.application.Platform;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ContentDisplay;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.layout.HBox;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Callback;

import java.util.concurrent.TimeUnit;

public class ComboBoxBindingApp extends Application {

    final static int INITIAL_FONT_SIZE = 8;
    final static int MAX_FONT_SIZE = 36;

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

    @Override
    public void start(Stage primaryStage) throws Exception {
        final ComboBox<String> cmb = new ComboBox();

        cmb.setCellFactory(new Callback<ListView<String>, ListCell<String>>() {
            @Override
            public ListCell<String> call(ListView<String> param) {
                return new ListCell<String>() {
                    {
                        setContentDisplay(ContentDisplay.TEXT_ONLY);
                    }

                    @Override
                    protected void updateItem(String item, boolean empty) {
                        super.updateItem(item, empty);

                        if (item == null || empty) {
                            setText(null);
                        } else {
                            setText(item);
                            setFont(new Font(Double.valueOf(item)));
                        }
                    }
                };
            }
        });

        HBox root = new HBox(10f);

        Button btn = new Button("Populate ComboBox");
        btn.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent event) {
                for (int i = INITIAL_FONT_SIZE; i <= MAX_FONT_SIZE; i += 2) {
                    cmb.getItems().add(String.valueOf(i));
                }
            }
        });

        Button btnClear = new Button("Clear");
        btnClear.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent event) {
                cmb.getItems().clear();
            }
        });

        Button btnSetEditable = new Button("Set editable");
        btnSetEditable.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent event) {
                //cmb.setEditable(true);
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        try {
                            TimeUnit.MILLISECONDS.sleep(256);
                        } catch (InterruptedException e) {
                            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
                        }

                        Platform.runLater(new Runnable() {
                            @Override
                            public void run() {
                                System.err.println("Binding editable property");
                                ObservableValue<? extends Boolean> _editableProperty = new SimpleBooleanProperty(true);
                                cmb.editableProperty().bind(_editableProperty);
                            }
                        });
                    }
                }).start();
            }
        });

        root.getChildren().addAll(cmb, btn, btnClear, btnSetEditable);

        Scene scene = new Scene(root, 500, 200);
        primaryStage.setScene(scene);
        primaryStage.show();

    }
}