import javafx.application.Application; import javafx.event.EventHandler; import javafx.scene.Scene; import javafx.scene.control.TreeTableColumn; import javafx.scene.control.TreeTableView; import javafx.scene.input.MouseEvent; import javafx.stage.Stage; public class TreeTableCCE extends Application { @Override public void start(Stage primaryStage) { TreeTableView ttv = new TreeTableView<>(); TreeTableColumn ttc = new TreeTableColumn<>(); ttc.setText("Hello"); ttv.getColumns().add(ttc); ttv.setOnMouseClicked(new EventHandler() { @Override public void handle(MouseEvent t) { ttc.setText("World"); } }); Scene scene = new Scene(ttv); primaryStage.setTitle("Hello World!"); primaryStage.setScene(scene); primaryStage.show(); } public static void main(String[] args) { Application.launch(args); } }