Class TreeItem

src/aria/tree/tree-item.ts:58–167

  },
})
export class TreeItem<V> extends DeferredContentAware implements OnInit, OnDestroy, HasElement {
  /** A reference to the host element. */
  private readonly _elementRef = inject(ElementRef);

  /** A reference to the host element. */
  readonly element = this._elementRef.nativeElement as HTMLElement;

  /** The owned tree item group. */
  private readonly _group = signal<TreeItemGroup<V> | undefined>(undefined);

  /** A unique identifier for the tree item. */
  readonly id = input(inject(_IdGenerator).getId('ng-tree-item-', true));

  /** The value of the tree item. */
  readonly value = input.required<V>();

  /** The parent tree root or tree item group. */
  readonly parent = input.required<Tree<V> | TreeItemGroup<V>>();

  /** Whether the tree item is disabled. */
  readonly disabled = input(false, {transform: booleanAttribute});

  /** Whether the tree item is selectable. */
  readonly selectable = input<boolean>(true);

  /** Whether the tree item is expanded. */
  readonly expanded = model<boolean>(false);

  /** Optional label for typeahead. Defaults to the element's textContent. */
  readonly label = input<string>();

  /** Search term for typeahead. */
  readonly searchTerm = computed(() => this.label() ?? this.element.textContent);

  /** The tree root. */
  readonly tree: Signal<Tree<V>> = computed(() => {
    if (this.parent() instanceof Tree) {
      return this.parent() as Tree<V>;
    }
    return (this.parent() as TreeItemGroup<V>).ownedBy().tree();
  });

  /** Whether the item is active. */
  readonly active = computed(() => this._pattern.active());

  /** The level of the current item in a tree. */
  readonly level = computed(() => this._pattern.level());

  /** Whether the item is selected. */
  readonly selected = computed(() => this._pattern.selected());

  /** Whether this item is visible due to all of its parents being expanded. */
  readonly visible = computed(() => this._pattern.visible());

  /** Whether the tree is expanded. Use this value for aria-expanded. */
  protected readonly _expanded: Signal<boolean | undefined> = computed(() =>
    this._pattern.expandable() ? this._pattern.expanded() : undefined,
  );