Bottom sheet menu with recyclerview faster thanks to Kotlin

bottom_sheet_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
    android:id="@+id/document_sign_type_recycler"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingTop="8dp"
    android:clipToPadding="false"
    xmlns:android="http://schemas.android.com/apk/res/android" />

BottomMenuItem.kt

data class BottomMenuItem(
        val resId: Int,
        val name: String,
        val action: () -> Unit
)

BottomSheetMenu.kt

import android.content.Context
import android.support.design.widget.BottomSheetDialog
import android.support.v7.widget.LinearLayoutManager
import android.view.LayoutInflater

/**
 * Created by costular on 29/08/17.
 */
class BottomSheetMenu(private val context: Context,
                      private val items: List<BottomMenuItem>) {

    private val bottomSheetDialog: BottomSheetDialog = BottomSheetDialog(context)

    init {
        val view = LayoutInflater.from(context).inflate(R.layout.bottom_sheet_menu, null)
        bottomSheetDialog.setContentView(view)

        with(view) {
            bottom_sheet_recycler.layoutManager = LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false)
            bottom_sheet_recycler.adapter = BottomSheetMenuAdapter(items)
        }
    }

    fun show() {
        bottomSheetDialog.show()
    }
}

BottomSheetMenuAdapter.kt

import android.support.v7.widget.RecyclerView
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup

/**
 * Created by costular on 29/08/17.
 */

class BottomSheetMenuAdapter(private val items: List<BottomMenuItem>) : RecyclerView.Adapter<BottomSheetMenuAdapter.BottomSheetMenuViewHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup?, viewType: Int): BottomSheetMenuViewHolder {
        return BottomSheetMenuViewHolder(LayoutInflater.from(parent!!.context).inflate(R.layout.item_context_bottom, parent, false))
    }

    override fun getItemCount(): Int = items.size

    override fun onBindViewHolder(holder: BottomSheetMenuViewHolder, position: Int) {
        holder.bind(items[position])
    }

    class BottomSheetMenuViewHolder(val view: View) : RecyclerView.ViewHolder(view) {

        fun bind(item: BottomMenuItem) {
            with(view) {
                bottom_menu_title.text = item.name
                bottom_menu_icon.setImageResource(item.resId)

                setOnClickListener { item.action() }
            }
        }
    }

}

item_bottom_sheet_menu

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/fragment_history_menu_bottom"
    android:layout_width="match_parent"
    android:layout_height="48dp"
    android:focusable="true"
    android:background="?attr/selectableItemBackground"
    app:layout_behavior="android.support.design.widget.BottomSheetBehavior">


    <ImageView
        android:id="@+id/bottom_menu_icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/bottom_menu_title"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="72dp"
        android:layout_marginRight="8dp"
        android:textSize="16sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

YourView.kt

fun showMenu() {
  val items = arrayListOf(
                BottomMenuItem(R.drawable.ic_document_automatic, "Edit", {
                    // edit action
                }),
                BottomMenuItem(R.drawable.ic_document_manual, "Delete", {
                    // delete action
                })
   )
   BottomSheetMenu(activity, items)
       .show()
}

Define globally in Your Adapter :

 var onItemClick : ((ItemViewModel) -> Unit)? = null

Inside onBindViewHolder add below code

       holder.imageView.setImageResource(itemsViewModel.image)
       holder.itemView.setOnClickListener(){
                val itemsViewModel = mList[position]
                onItemClick?.invoke(itemsViewModel)
            }

Then in your MainActivity call your onItemClick

        //Define Globally
        private lateinit var yourAdapter: YourAdapter
    
           // ArrayList of class ItemsViewModel
            val data = ArrayList<ItemViewModel>()
    
            // This loop will create 20 Views containing
            // the image with the count of view
            for (i in 1..20) {
                data.add(ItemViewModel(R.drawable.ic_calendar, "Scheme " + i))
            }
    
         
            yourAdapter= YourAdapter(data)
            // This will pass the ArrayList to our Adapter
            var adapter = calViewAdapter
    
            // Setting the Adapter with the recyclerview
            recyclerview.adapter = adapter
    
            yourAdapter.onItemClick = {
                 Toast.makeText(this@MainActivity , "Item clicked ", Toast.LENGTH_SHORT).show()
                //Do whatever you want to
            }