Consider and run the code below (you have to provide valid image paths).

The exact same ImageView shows a tooltip, when added directly to the scene. But ImageView does not show a Tooltip, when set as graphic of a ListCell.


import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.scene.Scene;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.control.Tooltip;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.Callback;

public class TestApp2 extends Application {

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

    @Override
    public void start(final Stage stage) throws Exception {


        ListView<String> listView = new ListView<>();
        listView.setItems(FXCollections.observableArrayList("test", "test"));
        listView.setCellFactory(new Callback<ListView<String>, ListCell<String>>() {
            @Override
            public ListCell<String> call(ListView<String> stringListView) {
                return new ListCell<String>() {
                    @Override
                    protected void updateItem(String item, boolean empty) {
                        super.updateItem(item, empty);
                        setGraphic(null);
                        if (!empty) {
                            ImageView imageView = new ImageView();
                            imageView.setImage(new Image("image.png"));
                            // Does NOT work as expected:
                            Tooltip.install(imageView, new Tooltip("That's a test"));
                            setGraphic(imageView);
                        }
                    }
                };
            }
        });

        ImageView imageView = new ImageView();
        imageView.setImage(new Image("image.png"));
        // Works as expected:
        Tooltip.install(imageView, new Tooltip("That's a test"));

        Scene scene = new Scene(new VBox(imageView, listView));
        stage.setScene(scene);
        stage.show();
    }
}