Generate QR Code in Android using Kotlin

package com.gtappdevelopers.kotlingfgproject

import android.graphics.Bitmap
import android.graphics.Point
import android.os.Bundle
import android.text.TextUtils
import android.view.Display
import android.view.WindowManager
import android.widget.Button
import android.widget.EditText
import android.widget.ImageView
import android.widget.Toast
import androidmads.library.qrgenerator.QRGContents
import androidmads.library.qrgenerator.QRGEncoder
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {

    // on below line we are creating a variable 
    // for our image view, edit text and a button.
    lateinit var qrIV: ImageView
    lateinit var msgEdt: EditText
    lateinit var generateQRBtn: Button

    // on below line we are creating
    // a variable for bitmap
    lateinit var bitmap: Bitmap

    // on below line we are creating 
    // a variable for qr encoder.
    lateinit var qrEncoder: QRGEncoder

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

        // on below line we are 
        // initializing our all variables.
        qrIV = findViewById(R.id.idIVQrcode)
        msgEdt = findViewById(R.id.idEdt)
        generateQRBtn = findViewById(R.id.idBtnGenerateQR)

        // on below line we are adding on click
        // listener for our generate QR button.
        generateQRBtn.setOnClickListener {
            // on below line we are checking if msg edit text is empty or not.
            if (TextUtils.isEmpty(msgEdt.text.toString())) {

                // on below line we are displaying toast message to display enter some text
                Toast.makeText(applicationContext, "Enter your message", Toast.LENGTH_SHORT).show()
            } else {
                // on below line we are getting service for window manager
                val windowManager: WindowManager = getSystemService(WINDOW_SERVICE) as WindowManager

                // on below line we are initializing a 
                // variable for our default display
                val display: Display = windowManager.defaultDisplay

                // on below line we are creating a variable
                // for point which is use to display in qr code
                val point: Point = Point()
                display.getSize(point)

                // on below line we are getting 
                // height and width of our point
                val width = point.x
                val height = point.y

                // on below line we are generating 
                // dimensions for width and height
                var dimen = if (width < height) width else height
                dimen = dimen * 3 / 4

                // on below line we are initializing our qr encoder
                qrEncoder = QRGEncoder(msgEdt.text.toString(), null, QRGContents.Type.TEXT, dimen)

                // on below line we are running a try 
                // and catch block for initializing our bitmap
                try {
                    // on below line we are 
                    // initializing our bitmap
                    bitmap = qrEncoder.encodeAsBitmap()

                    // on below line we are setting 
                    // this bitmap to our image view
                    qrIV.setImageBitmap(bitmap)
                } catch (e: Exception) {
                    // on below line we 
                    // are handling exception
                    e.printStackTrace()
                }
            }
        }
    }
}