1. JavaFX Tutorial
2. JavaFX Overview
3. Your First JavaFX Application
4. JavaFX Stage
5. JavaFX Scene
6. JavaFX Node
7. JavaFX Properties
8. JavaFX FXML
9. JavaFX CSS Styling
10. JavaFX ImageView
11. JavaFX Text
12. JavaFX Fonts
13. JavaFX Hyperlink
14. JavaFX Label
15. JavaFX Button
16. JavaFX MenuButton
17. JavaFX SplitMenuButton
18. JavaFX ToggleButton
19. JavaFX RadioButton
20. JavaFX CheckBox
21. JavaFX ChoiceBox
22. JavaFX ComboBox
23. JavaFX ListView
24. JavaFX DatePicker
25. JavaFX ColorPicker
26. JavaFX TextField
27. JavaFX PasswordField
28. JavaFX Slider
29. JavaFX TextArea
30. JavaFX ToolBar
31. JavaFX Tooltip
32. JavaFX ProgressBar
33. JavaFX FileChooser
34. JavaFX DirectoryChooser
35. JavaFX Accordion
36. JavaFX TitledPane
37. JavaFX SplitPane
38. JavaFX TabPane
39. JavaFX ScrollPane
40. JavaFX Group
41. JavaFX Region
42. JavaFX Pane
43. JavaFX HBox
44. JavaFX VBox
45. JavaFX Separator
46. JavaFX FlowPane
47. JavaFX TilePane
48. JavaFX GridPane
49. JavaFX MenuBar
50. JavaFX ContexMenu
51. JavaFX WebView
52. JavaFX PieChart
53. JavaFX TableView
54. JavaFX TreeView
55. JavaFX TreeTableView
56. JavaFX HTMLEditor
57. JavaFX Pagination
58. JavaFX BarChart
59. JavaFX StackedBarChart
60. JavaFX ScatterChart
61. JavaFX LineChart
62. JavaFX AreaChart
63. JavaFX StackedAreaChart
64. JavaFX Color
65. JavaFX 2D
66. JavaFX Effects
67. JavaFX 3D
68. JavaFX Transformation
69. JavaFX Animation
70. JavaFX Media - JavaFX Video and Audio Support
71. JavaFX Canvas
72. JavaFX Drag and Drop
73. JavaFX Concurrency

• Create a TreeView
• Add TreeView to Scene Graph
• Add Tree Items to TreeView
  • Add Children to a TreeItem
• Hide Root Item of TreeView

The JavaFX TreeeView enables you to display tree views inside your JavaFX applications. The JavaFX TreeView is represented by the class javafx.scene.control.TreeView . Here is a screenshot of a JavaFX TreeView:

Create a TreeView

You create a JavaFX TreeView simply by creating a new instance of the TreeView class. Here is an example of creating a new JavaFX TreeView instance:

TreeView treeView = new TreeView();

Add TreeView to Scene Graph

To make a JavaFX TreeView visible it must be added to the JavaFX scene graph. Here is an example showing how to add a JavaFX TreeView to the JavaFX scene graph:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TreeView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class TreeViewExample extends Application {

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

    @Override
    public void start(Stage primaryStage) {
        TreeView treeView = new TreeView();

        VBox vbox = new VBox(treeView);

        Scene scene = new Scene(vbox);

        primaryStage.setScene(scene);

        primaryStage.show();
    }

}

Notice, that the TreeView created in the above example will not have any items (nodes) to display. We will see how to add tree items to a TreeView in the next section.

Add Tree Items to TreeView

The items in the tree displayed by a JavaFX TreeView are represented by the TreeItem class (javafx.scene.control.TreeItem). Here is an example of creating a set of TreeItem instances and adding them to a JavaFX TreeView instance:

TreeItem rootItem = new TreeItem("Tutorials");

TreeItem webItem = new TreeItem("Web Tutorials");
webItem.getChildren().add(new TreeItem("HTML  Tutorial"));
webItem.getChildren().add(new TreeItem("HTML5 Tutorial"));
webItem.getChildren().add(new TreeItem("CSS Tutorial"));
webItem.getChildren().add(new TreeItem("SVG Tutorial"));
rootItem.getChildren().add(webItem);

TreeItem javaItem = new TreeItem("Java Tutorials");
javaItem.getChildren().add(new TreeItem("Java Language"));
javaItem.getChildren().add(new TreeItem("Java Collections"));
javaItem.getChildren().add(new TreeItem("Java Concurrency"));
rootItem.getChildren().add(javaItem);

TreeView treeView = new TreeView();
treeView.setRoot(rootItem);

Add Children to a TreeItem

If you look at the example in the previous section, you can see that a TreeItem can have other TreeItem instances as children. This parent-child relationship can continue recursively, indefinitely. This is how you structure the tree nodes logically in your JavaFX application. Here is an example that shows how to add child TreeItem instances to a parent TreeItem:

TreeItem javaItem = new TreeItem("Java Tutorials");
javaItem.getChildren().add(new TreeItem("Java Language"));
javaItem.getChildren().add(new TreeItem("Java Collections"));
javaItem.getChildren().add(new TreeItem("Java Concurrency"));

TreeItem rootItem = new TreeItem("Tutorials");
rootItem.getChildren().add(javaItem);

This example creates a tree with a single root TreeItem which has one child TreeItem set on it, and this child TreeItem has itself 3 child TreeItem instances added to it.

Hide Root Item of TreeView

You can hide the root item (root node) of a JavaFX TreeView. You do so by calling the setShowRoot() method, passing the boolean value false to it as parameter. Here is an example of hiding the root TreeItem of a JavaFX TreeView:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class TreeViewExample extends Application {

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

    @Override
    public void start(Stage primaryStage) {


        TreeItem rootItem = new TreeItem("Tutorials");

        TreeItem webItem = new TreeItem("Web Tutorials");
        webItem.getChildren().add(new TreeItem("HTML  Tutorial"));
        webItem.getChildren().add(new TreeItem("HTML5 Tutorial"));
        webItem.getChildren().add(new TreeItem("CSS Tutorial"));
        webItem.getChildren().add(new TreeItem("SVG Tutorial"));
        rootItem.getChildren().add(webItem);

        TreeItem javaItem = new TreeItem("Java Tutorials");
        javaItem.getChildren().add(new TreeItem("Java Language"));
        javaItem.getChildren().add(new TreeItem("Java Collections"));
        javaItem.getChildren().add(new TreeItem("Java Concurrency"));
        rootItem.getChildren().add(javaItem);

        TreeView treeView = new TreeView();
        treeView.setRoot(rootItem);

        treeView.setShowRoot(false);


        VBox vbox = new VBox(treeView);

        Scene scene = new Scene(vbox);

        primaryStage.setScene(scene);

        primaryStage.show();
    }

}

Notice the line in bold. That is the line that instructs the JavaFX TreeView to hide the root node. Here is a screenshot showing how the resulting JavaFX TreeView looks, with all nodes expanded:

Notice how the root TreeItem with the text Tutorials is not displayed.