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The problem starts with getParcelableArrayListExtra doesn't support type check when we try to set it to a variable. Let me give an example as basic as I can.

A User Class.

import kotlinx.parcelize.Parcelize
import android.os.Parcelable
    @Parcelize
    data class UserClass(
            var name: String? = null,
            var text: String? = null,
            var age: Int? = null
    ) : Parcelable
The random class which we'll try to set to the User variable.
import android.os.Parcelable
import kotlinx.parcelize.Parcelize
@Parcelize
data class MessageClass(
    val title: String?, = Constant.STRING_EMPTY
    val text: String? = Constant.STRING_EMPTY
) : Parcelable
The class that fills intent
class FillIntentClass(){
    //Let's say one of the developers added the MessageClass object inside our intent.
    //Or BE sent the wrong type of object and I passed its value to the intent.
    private fun DummyFunctionToSetIntent(){
    val messageList = arraylistOf(MessageClass(title = "hello",text ="dummy text")
    intent.putParcelableArrayListExtra(EXTRA_PAYMENT_OPTIONS_EXTRA, messageList)
Test class
class MyTestClass(){
  // UserList variable 
   private var mUserList: ArrayList<UserClass>? = null
   override fun onCreate(savedInstanceState: Bundle?) {
     with(intent) {
     // In this situation, mUserList became the type of ArrayList<MessageClass>
     // But it shouldn't be possible. Because it must accept only ArrayList<UserClass>
     // And that causes mostly crashes when the other code parts use it.
     mUserList = getParcelableArrayListExtra(EXTRA_PAYMENT_OPTIONS_EXTRA)
     // mUserList now pretend its like ArrayList<MessageClass>. But i set it as ArrayList<UserClass> at the top of the class.
     // The best way to solve this is to type check with as?. If the type is not as expected it must return null.
     // But I cannot use type check here. It gives me a "Not enough information to infer type variable T" error.
     mUserList = getParcelableArrayListExtra(EXTRA_PAYMENT_OPTIONS_EXTRA) as? ArrayList<UserClass> //(compile error here on IDE)
     // So I had to come out with the below solution. But I cannot say it's the best practice.
     if (getParcelableArrayListExtra<UserClass>(EXTRA_PAYMENT_OPTIONS_EXTRA)
            ?.filterIsInstance<UserClass>()?.isNotEmpty() == true
        mUserList = getParcelableArrayListExtra(EXTRA_PAYMENT_OPTIONS_EXTRA)
Type check(as,as?) works with getParcelable functions as expected. But when it comes to the getParcelableArrayListExtra it just doesn't work and gives compile error as I explained above.
Do you have any knowledge of what's the best option for as, as? check? And how it's possible for mUserList to accept a different type of Array and pretend like it?
                You aren't calling getParcelableArrayListExtra() on an Intent here. Have you implemented your own getParcelableArrayListExtra() method? Please put the code for that into the question.
– David Wasser
                Aug 8, 2022 at 10:39
This is a mess for a few reasons:
You are coding in Kotlin, but the classes you are dealing with (Parcelable, Bundle, Intent, ArrayList) are actually Java
Generics in Java are a hack
I would split the problem into 2 parts:
Unparcel the ArrayList into ArrayList<Parcelable>
Check/convert the contents of the ArrayList<Parcelable> into the expected type
Check the API level and code accordingly:
  if (Build.VERSION.SDK_INT >= 33) { 
    data = intent.getParcelableExtra (String name, Class<T> clazz)
}else{
    data = intent.getParcelableExtra("data")
Also you can use these extensions for bundle and intent:
inline fun <reified T : Parcelable> Intent.parcelable(key: String): T? = when {
  SDK_INT >= 33 -> getParcelableExtra(key, T::class.java)
  else -> @Suppress("DEPRECATION") getParcelableExtra(key) as? T
inline fun <reified T : Parcelable> Bundle.parcelable(key: String): T? = when {
  SDK_INT >= 33 -> getParcelable(key, T::class.java)
  else -> @Suppress("DEPRECATION") getParcelable(key) as? T
        
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