open class SimpleItem : AbstractItem<SimpleItem.ViewHolder>() {
    var name: String? = null
    var description: String? = null

    /** defines the type defining this item. must be unique. preferably an id */
    override val type: Int
        get() = R.id.fastadapter_sample_item_id

    /** defines the layout which will be used for this item in the list */
    override val layoutRes: Int
        get() = R.layout.sample_item

    override fun getViewHolder(v: View): ViewHolder {
        return ViewHolder(v)
    }

    class ViewHolder(view: View) : FastAdapter.ViewHolder<SimpleItem>(view) {
        var name: TextView = view.findViewById(R.id.material_drawer_name)
        var description: TextView = view.findViewById(R.id.material_drawer_description)

        override fun bindView(item: SimpleItem, payloads: List<Any>) {
            name.text = item.name
            description.text = item.name
        }

        override fun unbindView(item: SimpleItem) {
            name.text = null
            description.text = null
        }
    }
}

class BindingIconItem : AbstractBindingItem<IconItemBinding>() {
    var name: String? = null

    override val type: Int
        get() = R.id.fastadapter_icon_item_id

    override fun bindView(binding: IconItemBinding, payloads: List<Any>) {
        binding.name.text = name
    }

    override fun createBinding(inflater: LayoutInflater, parent: ViewGroup?): IconItemBinding {
        return IconItemBinding.inflate(inflater, parent, false)
    }
}

//create the ItemAdapter holding your Items
val itemAdapter = ItemAdapter<SimpleItem>()
//create the managing FastAdapter, by passing in the itemAdapter
val fastAdapter = FastAdapter.with(itemAdapter)

//set our adapters to the RecyclerView
recyclerView.setAdapter(fastAdapter)

//set the items to your ItemAdapter
itemAdapter.add(ITEMS)

// Gets (or creates and attaches if not yet existing) the extension from the given `FastAdapter`
val selectExtension = fastAdapter.getSelectExtension()
// configure as needed
selectExtension.isSelectable = true
selectExtension.multiSelect = true
selectExtension.selectOnLongClick = false
// see the API of this class for more options.

// Gets (or creates and attaches if not yet existing) the extension.
val expandableExtension = fastAdapter.getExpandableExtension()
// configure as needed
expandableExtension.isOnlyOneExpandedItem = true

fastAdapter.onClickListener = { view, adapter, item, position ->
    // Handle click here
    false
}

// just add an `EventHook` to your `FastAdapter` by implementing either a `ClickEventHook`, `LongClickEventHook`, `TouchEventHook`, `CustomEventHook`
fastAdapter.addEventHook(object : ClickEventHook<SimpleImageItem>() {
    override fun onBind(viewHolder: RecyclerView.ViewHolder): View? {
        //return the views on which you want to bind this event
        return if (viewHolder is SimpleImageItem.ViewHolder) {
            viewHolder.viewWhichReactsOnClick
        } else {
     null
 }
    }

    override fun onClick(v: View, position: Int, fastAdapter: FastAdapter<SimpleImageItem>, item: SimpleImageItem) {
        //react on the click event
    }
})

// Call this in onQueryTextSubmit() & onQueryTextChange() when using SearchView
itemAdapter.filter("yourSearchTerm")
itemAdapter.itemFilter.filterPredicate = { item: SimpleItem, constraint: CharSequence? ->
    item.name?.text.toString().contains(constraint.toString(), ignoreCase = true)
}

val dragCallback = SimpleDragCallback()
val touchHelper = ItemTouchHelper(dragCallback)
touchHelper.attachToRecyclerView(recyclerView)

override fun itemTouchOnMove(oldPosition: Int, newPosition: Int): Boolean {
    DragDropUtil.onMove(fastItemAdapter.itemAdapter, oldPosition, newPosition) // change position
    return true
}

// Header is a model class for your header
val headerAdapter = ItemAdapter<Header>()

val itemAdapter = GenericItemAdapter()

val fastAdapter: GenericFastAdapter = FastAdapter.with(headerAdapter, itemAdapter) //the order defines in which order the items will show up
// alternative the super type of both item adapters can be used. e.g.:
recyclerView.setAdapter(fastAdapter)

val footerAdapter = ItemAdapter<ProgressItem>()

recyclerView.addOnScrollListener(object : EndlessRecyclerOnScrollListener(footerAdapter) {
     override fun onLoadMore(currentPage: Int) {
         footerAdapter.clear()
         footerAdapter.add(ProgressItem())
         
  // Load your items here and add it to FastAdapter
         itemAdapter.add(NEWITEMS)
    }
})

val expandableExtension = fastAdapter.getExpandableExtension()

open class SimpleSubExpandableItem : AbstractExpandableItem<SimpleSubExpandableItem.ViewHolder>() {

    /**
     * BASIC ITEM IMPLEMENTATION
     */
}