RecyclerView Easy Adapting [refer to MainActivity.kt to see usage]

ListClick.java

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class ListClick implements RecyclerView.OnItemTouchListener {
    private GestureDetector gestureDetector;
    private ClickListener clickListener;

    public ListClick(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
        this.clickListener = clickListener;
        gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }

            @Override
            public void onLongPress(MotionEvent e) {
                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
                if (child != null && clickListener != null) {
                    clickListener.onLongClick(child, recyclerView.getChildAdapterPosition(child));
                }
            }
        });
    }
    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

        View child = rv.findChildViewUnder(e.getX(), e.getY());
        if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
            clickListener.onClick(child, rv.getChildAdapterPosition(child));
        }
        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {
    }

    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }



    public interface ClickListener {
        void onClick(View view, int position);

		/**
		* to Add support for extension methods you must use Java 8 or above
		* to do that Add this block to `build.gradle(Module: your module like app)` inside android block
			compileOptions {
				targetCompatibility 1.8
				sourceCompatibility 1.8
			}
		* This feature makes onLongClick optional
		*/
        default void onLongClick(View view, int position) {}
    }
}

ListConfig.kt

import android.content.Context
import android.support.v7.widget.LinearLayoutManager
import android.support.v7.widget.RecyclerView
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup

/**
 * Test of fast recyclerView adapter
 * usage:
 * ListConfig<String>(context).load(List<String>).holder{//holder init//}.layout(R.layout.li).bindViewHolder{//bindViewHolder//}.layoutManager(list)
 */
class ListConfig<Item>(var c: Context) {

    lateinit var set: List<Item>
    var resId = 0
    lateinit var bindViewHolder: (VH, Int, Item) -> Unit
    lateinit var list: RecyclerView

    fun with(list: RecyclerView): ListConfig<Item> {
        this.list = list
        return this
    }

    fun load(set: List<Item>): ListConfig<Item> {
        //we have list
        this.set = set
        return this
    }

    fun layout(resId: Int): ListConfig<Item> {
        //we have resId
        this.resId = resId
        return this
    }


    fun bindViewHolder(bindFun: (VH, Int, Item) -> Unit): ListConfig<Item> {
        this.bindViewHolder = bindFun
        //set it onRecyclerView
        list.layoutManager = LinearLayoutManager(c)
        list.setHasFixedSize(true)
        list.adapter = Adapter(set, resId, bindViewHolder)
        return this
    }

    fun layoutManager(lm: RecyclerView.LayoutManager): ListConfig<Item> {
        //set it onRecyclerView
        list.layoutManager = lm
        list.adapter = Adapter(set, resId, bindViewHolder)
        return this
    }

    fun onItemClick(click: (View?, Int)->Unit, longClick: (View?, Int)-> Unit) {
        list.addOnItemTouchListener(ListClick(c, list,
                object : ListClick.ClickListener{
                    override fun onClick(view: View?, position: Int) = click(view, position)
                    override fun onLongClick(view: View?, position: Int) = longClick(view, position)
                }))
    }

    fun onItemClick(click: (View?, Int)->Unit) =
        list.addOnItemTouchListener(ListClick(c, list, ListClick.ClickListener { view, position -> click(view, position) }))

    inner class Adapter(val set: List<Item>, private val layout: Int,
                        private val bindFun: (VH, Int, Item) -> Unit) :
            RecyclerView.Adapter<VH>() {
        override fun onCreateViewHolder(parent: ViewGroup?, viewType: Int) =
                VH(LayoutInflater.from(c).inflate(layout, parent, false))

        override fun getItemCount() = set.size

        override fun onBindViewHolder(holder: VH, position: Int) =
                bindFun(holder, position, set[position])

    }

    inner class VH(item: View) : RecyclerView.ViewHolder(item)
}

MainActivity.kt

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.support.v7.widget.GridLayoutManager
import android.support.v7.widget.RecyclerView
import android.support.v7.widget.Toolbar
import android.view.View
import android.widget.TextView
import android.widget.Toast
import ir.malv.list.ListConfig
import ir.malv.test07_01_2018.R
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        setSupportActionBar(findViewById(R.id.toolbar) as Toolbar)
        title = "East adapting"
        init()
    }

    private fun init() {
        val set = listOf("Item1", "Item2" /*, ...*/)
        ListConfig<String>(this) // Context as param and ViewHolder model as Generic param
                .with(list) // recyclerView
                .load(set) // list of Models (here it's a string)
                .layout(R.layout.li_1) // list item xml
                .bindViewHolder(this::listOnBind) // onBindViewHolder and ViewHolder itself
                .layoutManager(GridLayoutManager(this, 2)) // Optional LayoutManager (Linear by default)
                .onItemClick(this::listOnClick) // Click Listener
    }

    private fun listOnBind(holder: RecyclerView.ViewHolder, p: Int, s: String) {
        (holder.itemView.findViewById(R.id.text) as TextView).text = s
        //since the ViewHolder is empty you should create views here and use them
    }

    private fun listOnClick(v: View?, position: Int) {
        //Do something with the clicked View and it's position
    }
}