protected onEnter(tree: ITree, event: IKeyboardEvent): boolean {
		super.onEnter(tree, event);

		// grab the current selection for use later
		let selection = tree.getSelection();

		this.clickcb(selection[0], event, 'keyboard');
		tree.toggleExpansion(selection[0]);
		return true;
	}

	protected onEnter(tree: ITree, event: IKeyboardEvent): boolean {
		var payload = { origin: 'keyboard', originalEvent: event };

		if (tree.getHighlight()) {
			return false;
		}
		var focus = tree.getFocus();
		if (focus) {
			// In file browser, pressing enter key on an element will close dialog and call tree.dispose(). There should not be any tree events after selection.
			tree.setSelection([focus], payload);
		}
		return true;
	}

	private updateTreeVisibility(tree: ITree, isVisible: boolean): void {
		if (!tree) {
			return;
		}

		if (isVisible) {
			$(tree.getHTMLElement()).show();
		} else {
			$(tree.getHTMLElement()).hide(); // make sure the tree goes out of the tabindex world by hiding it
		}

		if (isVisible) {
			tree.onVisible();
		} else {
			tree.onHidden();
		}
	}

	protected onLeftClick(tree: ITree, element: any, event: IMouseEvent, origin: string = 'mouse'): boolean {
		// In file browser, double clicking an element calls tree.dispose(). There should not be any tree events after selection.
		if (event.detail === 2) {
			var payload = { origin: origin, originalEvent: event };
			if (tree.getInput() === element) {
				tree.clearFocus(payload);
				tree.clearSelection(payload);
			} else {
				var isMouseDown = event && event.browserEvent && event.browserEvent.type === 'mousedown';
				if (!isMouseDown) {
					event.preventDefault(); // we cannot preventDefault onMouseDown because this would break DND otherwise
				}
				event.stopPropagation();
				tree.DOMFocus();
				tree.setSelection([element], payload);
			}
			return true;
		} else {
			return super.onLeftClick(tree, element, event, origin);
		}
	}

	private focusTree(): void {
		if (!this.tree) {
			return; // return early if viewlet has not yet been created
		}

		// Make sure the current selected element is revealed
		const selection = this.tree.getSelection();
		if (selection.length > 0) {
			this.reveal(selection[0], 0.5).done(null, errors.onUnexpectedError);
		}

		// Pass Focus to Viewer
		this.tree.domFocus();
	}

	protected reveal(element: any, relativeTop?: number): TPromise<void> {
		if (!this.tree) {
			return TPromise.as(null); // return early if viewlet has not yet been created
		}

		return this.tree.reveal(element, relativeTop);
	}

	public dispose(): void {
		this.isDisposed = true;
		this.treeContainer = null;

		if (this.tree) {
			this.tree.dispose();
		}

		if (this.dragHandler) {
			this.dragHandler.dispose();
		}

		this.toDispose = dispose(this.toDispose);

		if (this.toolBar) {
			this.toolBar.dispose();
		}

		super.dispose();
	}

	public layoutBody(size: number): void {
		if (this.tree) {
			this.treeContainer.style.height = size + 'px';
			this.tree.layout(size);
		}
	}