How to delete a specific TreeItem from the TreeView in javafx?
I’ve got a TreeView called foodTree to which I’ve added some TreeItem. The code :
import javafx.application.Application ; import javafx.scene.Scene ; import javafx.event.* ; import javafx.stage.* ; import javafx.scene.layout.* ; import javafx.scene.control.* ; import javafx.geometry.* ; import javafx.scene.control.cell.PropertyValueFactory ; import javafx.collections.* ; public class Tree extends Application { TreeView foodTree ; public static void main(String[] args) { Application.launch(args) ; } @Override public void start(Stage window) { TreeItem<String> root, vegetables, fruits ; root = new TreeItem<>() ; root.setExpanded(true) ; vegetables = makeBranch("Vegies", root) ; makeBranch("Cabbage", vegetables) ; makeBranch("Beans", vegetables) ; fruits = makeBranch("Fruits", root) ; makeBranch("Apples", fruits) ; makeBranch("Mangoes", fruits) ; foodTree = new TreeView<>(root) ; foodTree.setShowRoot(false) ; foodTree.setPrefWidth(180) ; foodTree.setMaxSize(Region.USE_PREF_SIZE, Region.USE_PREF_SIZE) ; BorderPane b_pane = new BorderPane() ; b_pane.setLeft(foodTree) ; Scene scene = new Scene(b_pane, 300, 200) ; window.setScene(scene) ; window.show() ; } public TreeItem<String> makeBranch(String title, TreeItem<String> parent) { TreeItem<String> item = new TreeItem<>(title) ; item.setExpanded(false) ; parent.getChildren().add(item) ; return item ; } } I wish to know how to delete a TreeItem from the TreeView – how can I delete Mangoes so that it’s not displayed in the TreeView?
To remove a tree item, you need to remove it from the list returned by its parent’s getChildren() method. If you have a reference to the item to be removed, this is straightforward. For example, if you do
// makeBranch("Mangoes", fruits) ; TreeItem<String> mangoes = makeBranch("Mangoes", fruits) ; then later you can simply remove the item from its parent:
mangoes.getParent().getChildren().remove(mangoes); In this case, since you know the parent, you could also just do
fruits.getChildren().remove(mangoes); You can also use any of the standard methods defined in List on the parent’s getChildren(), e.g.
// remove any items from fruits whose value is "Mangoes": fruits.getChildren().removeIf(treeItem -> treeItem.getValue().equals("Mangoes")); // remove the first child from fruits: fruits.getChildren().remove(0); 
