CollectionViewClassifyMenu is an Objective-C iOS demo project that builds categorized menus using UICollectionView. It demonstrates a two-level classification menu where the second-level menu can collapse and expand. The project also includes a sidebar-style menu with multi-select behavior for filtering choices. It supports persistence of selected filter conditions, so the app can remember the user’s previous menu state after reopening. The demo uses NSCoding for saving filter data and includes a way to clear saved settings at launch. ...