Javafx TreeView Directory Listing

Question

I'm trying to create a TreeView which displays directory contents such as:

ABC
    BCD
    123.php

Where ABC and BCD are both directories. I feel like I'm missing something as the TreeView works fine before I strip out the full directory location but once I strip it, it won't display like the above.

public void displayTreeView(String inputDirectoryLocation, CheckBoxTreeItem<String> mainRootItem) {

    // Creates the root item.
    CheckBoxTreeItem<String> rootItem = new CheckBoxTreeItem<>(inputDirectoryLocation);

    // Hides the root item of the tree view.
    treeView.setShowRoot(false);

    // Creates the cell factory.
    treeView.setCellFactory(CheckBoxTreeCell.<String>forTreeView());

    // Get a list of files.
    File fileInputDirectoryLocation = new File(inputDirectoryLocation);
    File fileList[] = fileInputDirectoryLocation.listFiles();

    // Loop through each file and directory in the fileList.
    for (int i = 0; i < fileList.length; i++) {

        // Check if fileList[i] is a file or a directory.
        if (fileList[i].isDirectory()) {

            // Re-iterate through as is directory.
            displayTreeView(fileList[i].toString(), rootItem);

        } else {

            // Check the file type of the file.
            String fileType = Util.retrieveFileType(fileList[i].toString());

            // Check if the file type is the same file type we are searching for. In the future we just add the or symbol to support other file types.
            if (fileType.equals(".php")) {

                // Creates the item.
                CheckBoxTreeItem<String> fileCheckBoxTreeItem = new CheckBoxTreeItem<>(fileList[i].getName());

                // Adds to the treeview.
                rootItem.getChildren().add(fileCheckBoxTreeItem);
            }
        }
    }

    // Check if the mainRootItem has been specified.
    if (mainRootItem == null) {

        // Sets the tree view root item.
        treeView.setRoot(rootItem);
    } else {

        // Creates the root item.
        CheckBoxTreeItem<String> dirCheckBoxTreeItem = new CheckBoxTreeItem<>(fileInputDirectoryLocation.getName());

        // Sets the sub-root item.
        mainRootItem.getChildren().add(dirCheckBoxTreeItem);
    }
}

Answer 1

By combining the initialisation of the TreeView and a recursive method for constructing the tree you created messy code.

Better create a new method just for creating the tree:

public static void createTree(File file, CheckBoxTreeItem<String> parent) {
    if (file.isDirectory()) {
        CheckBoxTreeItem<String> treeItem = new CheckBoxTreeItem<>(file.getName());
        parent.getChildren().add(treeItem);
        for (File f : file.listFiles()) {
            createTree(f, treeItem);
        }
    } else if (".php".equals(Util.retrieveFileType(file.toString()))) {
        parent.getChildren().add(new CheckBoxTreeItem<>(file.getName()));
    }
}

and use it in your displayTreeView method

public void displayTreeView(String inputDirectoryLocation) {
    // Creates the root item.
    CheckBoxTreeItem<String> rootItem = new CheckBoxTreeItem<>(inputDirectoryLocation);

    // Hides the root item of the tree view.
    treeView.setShowRoot(false);

    // Creates the cell factory.
    treeView.setCellFactory(CheckBoxTreeCell.<String>forTreeView());

    // Get a list of files.
    File fileInputDirectoryLocation = new File(inputDirectoryLocation);
    File fileList[] = fileInputDirectoryLocation.listFiles();

    // create tree
    for (File file : fileList) {
        createTree(file, rootItem);
    }

    treeView.setRoot(rootItem);
}

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BTW: Your issue is caused by creating the tree structure and ignoring it for every node but the root (for non-root items the only node added to rootItem; for items other than the root you add is the "flat" dirCheckBoxTreeItem to the parent instead).