/// <summary>
        /// Updates whether this <see cref="SelectionHandler{T}"/> is visible.
        /// </summary>
        private void updateVisibility()
        {
            // fix the case that only selected blueprint in current handler can show selection box.
            // todo : this is the temp way, might remove after official fix that.
            bool visible = containsSelectionInCurrentBlueprintContainer();

            SelectionBox.FadeTo(visible ? 1f : 0.0f);
        }