How to add RecyclerView item Swipe to Dismiss in Kotlin

In this android kotlin source code example, we are going to add RecyclerView item Swipe to Dismiss in Kotlin.

You can copy and adopt this source code example to your Kotlin android project without reinventing the wheel.

Below is a step by step source code to add RecyclerView item Swipe to Dismiss in Kotlin.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".recyclerView.RecyclerViewActivity11">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.kt

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.recyclerview.widget.RecyclerView
import com.bluapp.kotlinview.R
import androidx.recyclerview.widget.ItemTouchHelper
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.LinearLayoutManager
import android.widget.TextView
import android.view.LayoutInflater
import android.view.ViewGroup
import android.widget.Toast
import android.content.Context
import android.view.View


class RecyclerViewActivity11 : AppCompatActivity() {
    private var list: RecyclerView? = null
    private var recyclerAdapter: adapter? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_recycler_view11)
        list = findViewById(R.id.list) as RecyclerView
        val country = arrayListOf<String>()
        country.add("Nigeria")
        country.add("China")
        country.add("USA")
        country.add("Ghana")
        country.add("Canada")
        country.add("Finland")
        country.add("Denmark")
        country.add("Argentina")
        country.add("Andorra")
        country.add("Togo")

        val layoutManager = LinearLayoutManager(this)
        list!!.setLayoutManager(layoutManager)
        recyclerAdapter = adapter(this@RecyclerViewActivity11, country)
        list!!.addItemDecoration(DividerItemDecoration(list!!.getContext(), layoutManager.orientation))
        list!!.setAdapter(recyclerAdapter)
        val itemTouchHelper = ItemTouchHelper(simpleCallback)
        itemTouchHelper.attachToRecyclerView(list)
    }

    var simpleCallback: ItemTouchHelper.SimpleCallback = object : ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT or ItemTouchHelper.DOWN or ItemTouchHelper.UP) {
        override fun onMove(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, viewHolder1: RecyclerView.ViewHolder): Boolean {
            Toast.makeText(this@RecyclerViewActivity11, "Move", Toast.LENGTH_SHORT).show()
            return false
        }

        override fun onSwiped(viewHolder: RecyclerView.ViewHolder, i: Int) {
            Toast.makeText(this@RecyclerViewActivity11, "Swipe To Delete", Toast.LENGTH_SHORT).show()
            val position = viewHolder.adapterPosition
            recyclerAdapter!!.deleteItem(position)
        }
    }


    private inner class adapter(internal var context: Context, internal var mData: MutableList<String>) : RecyclerView.Adapter<adapter.myViewHolder>() {
        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): adapter.myViewHolder {
            val view = LayoutInflater.from(context).inflate(com.bluapp.kotlinview.R.layout.recyclerview_adapter1, parent, false)
            return myViewHolder(view)
        }
        fun deleteItem(position: Int) {
            mData.removeAt(position)
            notifyItemRemoved(position)
        }
        override fun onBindViewHolder(holder: adapter.myViewHolder, position: Int) {
            holder.country.text = mData[position]
        }
        override fun getItemCount(): Int {
            return mData.size
        }
        inner class myViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
            internal var country: TextView
            init {
                country = itemView.findViewById(R.id.country)
            }
        }
    }

}

recyclerview_adapter1.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="10dp">

    <TextView
        android:id="@+id/country"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:text="Country"
        android:textColor="#000000"
        android:textSize="18sp"
        android:textStyle="bold" />

</RelativeLayout>