Android Studio Beginner here - kotlin

Question

I am taking the coursera course for mobile application development and I am doing my first project, my build launches successfully then immediately crashes. I am not sure why it is doing this so any insight into the matter would be greatly appreciated. Below is my build...
package com.example.video_player
import android.R
import android.net.Uri
import android.net.Uri.*
import android.os.Bundle
import android.widget.MediaController
import android.widget.VideoView
import androidx.appcompat.app.AppCompatActivity
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val videoView = findViewById(R.id.testView)
val mediaController = MediaController(this)
mediaController.setAnchorView(videoView)
val uri:Uri = parse(
"android.resource://" + packageName
+ "/raw/test"
)
videoView.setMediaController(mediaController)
videoView.setVideoURI(uri)
videoView.requestFocus()
videoView.start()
}
}
<?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="com.example.video_player.MainActivity">
<VideoView
android:id="#+id/testView"
android:layout_width="wrap_content"
android:layout_height="308dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
This is my first build and i am following a tutorial and am just getting error after error, when i get the errors to clear the app crashes directly after launch.