//activity_main.xml(file 1)
<?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=".MainActivity">

    <TextView
        android:id="@+id/textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Demonstration of Activity LIFE CYCLE Methods"
        android:textColor="@color/design_default_color_error"
        android:textSize="18sp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintVertical_bias="0.5"
        app:layout_constraintHorizontal_bias="0.5"/>
</androidx.constraintlayout.widget.ConstraintLayout>

//MainActivity.ktfile(file 2)
import android.os.Bundle
import android.widget.Toast
import androidx.activity.enableEdgeToEdge
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.ViewCompat
import androidx.core.view.WindowInsetsCompat

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContentView(R.layout.activity_main)
        Toast.makeText(applicationContext,"ONCREATE() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onStart()
    {
        super.onStart()
        Toast.makeText(applicationContext,"ONSTART() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onRestart()
    {
        super.onRestart()
        Toast.makeText(applicationContext,"ONRESTART() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onResume()
    {
        super.onResume()
        Toast.makeText(applicationContext,"ONRESUME() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onPause()
    {
        super.onPause()
        Toast.makeText(applicationContext,"ONPAUSE() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onStop()
    {
        super.onStop()
        Toast.makeText(applicationContext,"ONSTOP() CALLED",Toast.LENGTH_SHORT).show()
    }
    override fun onDestroy()
    {
        super.onDestroy()
        Toast.makeText(applicationContext,"ONDESTROY() CALLED",Toast.LENGTH_SHORT).show()
    }

}