Javafx 2 TreeView Filtering

Question

How is it possible to filter Nodes in a JavaFX 2 TreeView?

I have a TextField and I want to filter all Nodes (for example node labels) based on the content of the TextField.

Thanks.

Answer 1

this is reusable filterable tree item class i've wrote.

the filter should be bound on predicateProperty, and you must use getSourceChildren method to manipulate tree items.

public class FilterableTreeItem<T> extends TreeItem<T> {
    private final ObservableList<TreeItem<T>> sourceChildren = FXCollections.observableArrayList();
    private final FilteredList<TreeItem<T>> filteredChildren = new FilteredList<>(sourceChildren);
    private final ObjectProperty<Predicate<T>> predicate = new SimpleObjectProperty<>();

    public FilterableTreeItem(T value) {
        super(value);

        filteredChildren.predicateProperty().bind(Bindings.createObjectBinding(() -> {
            Predicate<TreeItem<T>> p = child -> {
                if (child instanceof FilterableTreeItem) {
                    ((FilterableTreeItem<T>) child).predicateProperty().set(predicate.get());
                }
                if (predicate.get() == null || !child.getChildren().isEmpty()) {
                    return true;
                }
                return predicate.get().test(child.getValue());
            };
            return p;
        } , predicate));

        filteredChildren.addListener((ListChangeListener<TreeItem<T>>) c -> {
            while (c.next()) {
                getChildren().removeAll(c.getRemoved());
                getChildren().addAll(c.getAddedSubList());
            }
        });
    }

    public ObservableList<TreeItem<T>> getSourceChildren() {
        return sourceChildren;
    }

    public ObjectProperty<Predicate<T>> predicateProperty() {
        return predicate;
    }

}

Answer 2

There is no special filter, provided by JFX.

So you should implement it by yourself.

The only support from JFX you have - tracking of collection of TreeItems' items. When you add or remove an item, it will be added or removed. But adding or removing from collections you implement yourself.