How to generate FileTree in JavaFX?

Question

I am newbie in Java and JavaFX and I am working on a GUI application which use SplitPane. In one pane i am trying to display filetree and in other i have successfully added TabPane. Using filetree users will be open the files in the form of tabs.

I am using this code to generate the file tree.

public class FilesTree1 implements Runnable {

static CustomTree filetree = new CustomTree();

public static TreeView treeview;

//File f = new File("workspace");
int timeout = 0;

public FilesTree1() {

    //  this.getTree();
}

private TreeView buildFileSystemBrowser() {
    TreeItem root = createNode(new File("workspace"));
    return new TreeView(root);
}


private TreeItem createNode(final File f) {
    TreeItem treeItem = null;
    if (f.isDirectory() && f.listFiles() == null) {
        return treeItem = new TreeItem("Empty");

    }
    File[] tempfilelist = f.listFiles();

    for (int i = 0; i < tempfilelist.length; i++) {
        if (tempfilelist[i].isDirectory()) {
            System.out.println("- " + tempfilelist[i]);
            treeItem = new TreeItem(createNode(tempfilelist[i]));
        } else {
            treeItem = new TreeItem((tempfilelist[i].getAbsolutePath()));
            System.out.println("- " + tempfilelist[i]);

        }

    }
    return treeItem;
}

@Override
public void run() {
    while (true) {
        try {
            //        filetree.setSimpleRoot(f.getName());

            treeview = this.buildFileSystemBrowser();
            treeview.getRoot().setExpanded(true);
            Thread.sleep(100000);
        } catch (InterruptedException ex) {
        }
    }
}
}

In main class i am calling this function to add tree in the Pane.

static Tab tab41 = new Tab("Files");

public void synchroniseUi() {
   Platform.runLater(new Runnable() {
        @Override
        public void run() {
            tab41.setContent(FilesTree1.treeview);
        }
    });
 }

But the problem is that tree is not appearing in the Pane.

Edit: tab41 is a Tab in SplitPane :)

Answer 1

Ok so i finally solved the problem, Here is my latest working code. Hopefully it may be useful for other.

public class FilesTree implements Runnable {

static CustomTree filetree = new CustomTree();
;
public static TreeView<File> tv = new TreeView();
public static Image folderCollapseImage = new Image(ClassLoader.getSystemResourceAsStream("ui/folder.png"));
public static Image folderExpandImage = new Image(ClassLoader.getSystemResourceAsStream("ui/folder-open.png"));
public static Image fileImage = new Image(ClassLoader.getSystemResourceAsStream("ui/file.png"));

SQLiteJDBC treedb = new SQLiteJDBC();
String sql;
ResultSet rs;
int totalFolder = 0;
int totalFile = 0;
File[] filelist;
File f = new File("workspace");
int timeout = 0;

public FilesTree() {

    //  this.getTree();
}

private TreeView buildFileSystemBrowser() {
    TreeItem<File> root = createNode(new File("workspace"));
    return new TreeView<File>(root);
}

// This method creates a TreeItem to represent the given File. It does this
// by overriding the TreeItem.getChildren() and TreeItem.isLeaf() methods 
// anonymously, but this could be better abstracted by creating a 
// 'FileTreeItem' subclass of TreeItem. However, this is left as an exercise
// for the reader.
private TreeItem<File> createNode(final File f) {
    return new TreeItem<File>(f) {
        // We cache whether the File is a leaf or not. A File is a leaf if
        // it is not a directory and does not have any files contained within
        // it. We cache this as isLeaf() is called often, and doing the 
        // actual check on File is expensive.
        private boolean isLeaf;

        // We do the children and leaf testing only once, and then set these
        // booleans to false so that we do not check again during this
        // run. A more complete implementation may need to handle more 
        // dynamic file system situations (such as where a folder has files
        // added after the TreeView is shown). Again, this is left as an
        // exercise for the reader.
        private boolean isFirstTimeChildren = true;
        private boolean isFirstTimeLeaf = true;

        @Override
        public ObservableList<TreeItem<File>> getChildren() {
            if (isFirstTimeChildren) {
                isFirstTimeChildren = false;

                // First getChildren() call, so we actually go off and 
                // determine the children of the File contained in this TreeItem.
                super.setExpanded(true);
                this.setExpanded(true);
                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;
        }

        private ObservableList<TreeItem<File>> buildChildren(TreeItem<File> TreeItem) {
            File f = TreeItem.getValue();
            if (f != null && f.isDirectory()) {
                // super.setGraphic(new ImageView(folderCollapseImage));
                File[] files = f.listFiles();
                TreeItem.setExpanded(true);
                if (files != null) {
                    ObservableList<TreeItem<File>> children = FXCollections.observableArrayList();

                    for (int i = 0; i < files.length; i++) {

                        children.add(createNode(files[i]));
                        if (files[i].isDirectory()) {
                            children.get(i).setGraphic(new ImageView(folderCollapseImage));
                        } else {
                            children.get(i).setGraphic(new ImageView(fileImage));

                        }
                        children.get(i).addEventHandler(TreeItem.branchCollapsedEvent(), new EventHandler() {
                            @Override
                            public void handle(Event e) {
                                TreeItem<File> source = (TreeItem<File>) e.getSource();
                               File source2= source.getValue();
                                if (source2.isDirectory() && !source.isExpanded()) {
                                    ImageView iv = (ImageView) source.getGraphic();
                                    iv.setImage(folderCollapseImage);
                                }
                            }
                        });
                        children.get(i).addEventHandler(TreeItem.branchExpandedEvent(), new EventHandler() {
                            @Override
                            public void handle(Event e) {
                                TreeItem<File> source = (TreeItem<File>) e.getSource();
                               File source2= source.getValue();
                                if (source2.isDirectory() && source.isExpanded()) {
                                    ImageView iv = (ImageView) source.getGraphic();
                                    iv.setImage(folderExpandImage);
                                }
                            }
                        });

                    }
                    return children;
                }
            }

            return FXCollections.emptyObservableList();
        }
    };
}

@Override
public void run() {
    //while (true) 
    {
        filetree.setSimpleRoot(f.getName());
        tv = this.buildFileSystemBrowser();
        tv.getRoot().setExpanded(true);
        //tv.setSelectionModel(null);
        tv.setOnMouseClicked(new EventHandler<MouseEvent>() {
            @Override
            public void handle(MouseEvent mouseEvent) {
                if (mouseEvent.getClickCount() % 2 == 0) {
                    MultipleSelectionModel msm = tv.getSelectionModel();
                    TreeItem<File> item = (TreeItem<File>) msm.getSelectedItem();
                    System.out.println("Selected Text : " + item.getValue());

                    // Create New Tab
                } else {

                    MultipleSelectionModel msm = tv.getSelectionModel();
                    TreeItem<File> item = (TreeItem<File>) msm.getSelectedItem();
                    System.out.println("Selected Text : " + item.getValue().getAbsolutePath());

                }
            }
        });
    }
 }
}

EDIT:

Improved The Answer :)

I am learning and experimenting the code. No hard feelings (so no need to downvote, How one can learn if you keep discouraging? instead help the one to improve and learn, eventually he/she will get it right)