TreeTableView Scrollbar Not Responsive Once Node is Collapsed

Question

I've created a TreeTableView using a folder/file structure, I start all of the tree nodes to be expanded.  The vertical scrollbar does respond at that point as expected by scrolling the treatable content.  However, if I collapse one of the parent nodes the vertical scrollbar does not scroll the content consistently.  Sometimes it works and sometimes the content does not scroll at all, when I re-expand the node it still does not reset the vertical scrollbar.
I'm using Java(TM) SE Runtime Environment (build 1.8.0-ea-b114) on Mac OSx Mavericks.

Answer 1

package treetablescrollingbug;
import java.io.File;
import java.text.DateFormat;
import java.text.NumberFormat;
import java.util.Comparator;
import java.util.Date;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyObjectWrapper;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeTableCell;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeTableView;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;
import javafx.util.Callback;
public class TreeTableScrollingBug extends Application {
    private final static NumberFormat NumberFormater = NumberFormat.getIntegerInstance();
    private final static DateFormat DateFormater = DateFormat.getDateTimeInstance();
    private TreeTableView<File> treeTblFolderStructure;
    @Override
    public void start(Stage primaryStage) {
        this.treeTblFolderStructure = new TreeTableView<>();
        this.buildFileBrowserTreeTableView();
        AnchorPane root = new AnchorPane();
        AnchorPane.setTopAnchor(this.treeTblFolderStructure, 10.0);
        AnchorPane.setLeftAnchor(this.treeTblFolderStructure, 10.0);
        AnchorPane.setRightAnchor(this.treeTblFolderStructure, 10.0);
        AnchorPane.setBottomAnchor(this.treeTblFolderStructure, 10.0);
        root.getChildren().add(this.treeTblFolderStructure);
        Scene scene = new Scene(root, 640, 480);
        primaryStage.setTitle("TreeTableView Vertical ScrollBar BUG");
        primaryStage.setScene(scene);
        primaryStage.show();
    private void buildFileBrowserTreeTableView() {
    TreeItem<File> root = createNode(new File("/Library/Java/JavaVirtualMachines/jdk1.8.0.jdk"));
    root.setExpanded(true);
    this.treeTblFolderStructure.setShowRoot(true);
    this.treeTblFolderStructure.setRoot(root);
    // --- name column
    TreeTableColumn<File, String> nameColumn = new TreeTableColumn<File, String>("Name");
    nameColumn.setPrefWidth(300);
    nameColumn.setCellValueFactory(
            new Callback<TreeTableColumn.CellDataFeatures<File, String>, ObservableValue<String>>() {
        @Override
        public ObservableValue<String> call(TreeTableColumn.CellDataFeatures<File, String> p) {
            File f = p.getValue().getValue();
            String text = f.getParentFile() == null ? "/" : f.getName();
            return new ReadOnlyObjectWrapper<String>(text);
    // --- size column
    TreeTableColumn<File, File> sizeColumn = new TreeTableColumn<File, File>("Size");
    sizeColumn.setPrefWidth(100);
    sizeColumn.setCellValueFactory(new Callback<TreeTableColumn.CellDataFeatures<File, File>, ObservableValue<File>>() {
        @Override public ObservableValue<File> call(TreeTableColumn.CellDataFeatures<File, File> p) {
            return new ReadOnlyObjectWrapper<File>(p.getValue().getValue());
    sizeColumn.setCellFactory(new Callback<TreeTableColumn<File, File>, TreeTableCell<File, File>>() {
        @Override public TreeTableCell<File, File> call(final TreeTableColumn<File, File> p) {
            return new TreeTableCell<File, File>() {
                @Override protected void updateItem(File item, boolean empty) {
                    super.updateItem(item, empty);
                    TreeTableView treeTable = p.getTreeTableView();
                    // if the File is a directory, it has no size...
//                    if (getIndex() >= treeTable.impl_getTreeItemCount())
//                        setText(null);
//                    else
                        TreeItem<File> treeItem = treeTable.getTreeItem(getIndex());
                        if (item == null || empty || treeItem == null ||
                                treeItem.getValue() == null || treeItem.getValue().isDirectory()) {
                            setText(null);
                        } else {
                            setText(NumberFormater.format(item.length()) + " KB");
    sizeColumn.setComparator(new Comparator<File>() {
        @Override public int compare(File f1, File f2) {
            long s1 = f1.isDirectory() ? 0 : f1.length();
            long s2 = f2.isDirectory() ? 0 : f2.length();
            long result = s1 - s2;
            if (result < 0) {
                return -1;
            } else if (result == 0) {
                return 0;
            } else {
                return 1;
    // --- modified column
    TreeTableColumn<File, Date> lastModifiedColumn = new TreeTableColumn<File, Date>("Last Modified");
    lastModifiedColumn.setPrefWidth(130);
    lastModifiedColumn.setCellValueFactory(new Callback<TreeTableColumn.CellDataFeatures<File, Date>, ObservableValue<Date>>() {
        @Override public ObservableValue<Date> call(TreeTableColumn.CellDataFeatures<File, Date> p) {
            return new ReadOnlyObjectWrapper<Date>(new Date(p.getValue().getValue().lastModified()));
    lastModifiedColumn.setCellFactory(new Callback<TreeTableColumn<File, Date>, TreeTableCell<File, Date>>() {
        @Override public TreeTableCell<File, Date> call(TreeTableColumn<File, Date> p) {
            return new TreeTableCell<File, Date>() {
                @Override protected void updateItem(Date item, boolean empty) {
                    super.updateItem(item, empty);
                    if (item == null || empty) {
                        setText(null);
                    } else {
                        setText(DateFormater.format(item));
    this.treeTblFolderStructure.getColumns().setAll(nameColumn, sizeColumn, lastModifiedColumn);
private TreeItem<File> createNode(final File f) {
    final TreeItem<File> node = new TreeItem<File>(f) {
        private boolean isLeaf;
        private boolean isFirstTimeChildren = true;
        private boolean isFirstTimeLeaf = true;
        @Override public ObservableList<TreeItem<File>> getChildren() {
            if (isFirstTimeChildren) {
                isFirstTimeChildren = false;
                super.getChildren().setAll(buildChildren(this));
            return super.getChildren();
        @Override public boolean isLeaf() {
            if (isFirstTimeLeaf) {
                isFirstTimeLeaf = false;
                File f = (File) getValue();
                isLeaf = f.isFile();
            return isLeaf;
    node.setExpanded(true);
    return node;
private ObservableList<TreeItem<File>> buildChildren(TreeItem<File> TreeItem) {
    File f = (File) TreeItem.getValue();
    if (f != null && f.isDirectory()) {
        File[] files = f.listFiles();
        if (files != null) {
            ObservableList<TreeItem<File>> children = FXCollections.observableArrayList();
            for (File childFile : files) {
                children.add(createNode(childFile));
            return children;
    return FXCollections.emptyObservableList();
    public static void main(String[] args) {
        launch(args);