Spinner in Kotlin

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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=".MainActivity"
    android:orientation="vertical">

    <Spinner
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/spin"
        android:background="#fff"></Spinner>

    

</LinearLayout>

MainActivity.kt

package com.androinidan.spinner

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.AdapterView
import android.widget.ArrayAdapter
import android.widget.AutoCompleteTextView
import android.widget.Spinner
import android.widget.Toast

class MainActivity : AppCompatActivity() {

    var studentdata= arrayOf("Ashih","Swathi","Anuj","Raj", "Ashih","Swathi","Anuj","Raj",
        "Ashih","Swathi","Anuj","Raj", "Ashih","Swathi","Anuj","Raj","Ashih","Swathi","Anuj","Raj","451536234")

    var spinner: Spinner?=null


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        spinner=findViewById(R.id.spin)

        var adp: ArrayAdapter<*>

        adp= ArrayAdapter(applicationContext,android.R.layout.simple_list_item_1,studentdata)

        spinner!!.adapter=adp


        spinner!!.onItemSelectedListener = object :
            AdapterView.OnItemSelectedListener {
            override fun onItemSelected(parent: AdapterView<*>,
                                        view: View, position: Int, id: Long) {
                Toast.makeText(this@MainActivity,
                    " "+position, Toast.LENGTH_SHORT).show()
            }

            override fun onNothingSelected(parent: AdapterView<*>) {
                // write code to perform some action
            }
        }


    }

    }