ArrayList 上的 Android intent.getParcelableArrayListExtra 引发 Nullpointer 异常

我正在try 将LatLng对象的数组列表传递给另一个活动.该方法是在不是活动的Util类中定义的.但接受活动总是筹集NullpointerException美元

class Utils {
    companion object {
        fun startMaps(pairs: MutableList<LatLng>){
            var intent = Intent(AAddressActivity.appContext, MapActivity::class.java)
            Log.d("pair", ArrayList(pairs).toString())
            Log.d("pair", ArrayList(pairs)[0].toString())
            intent.putParcelableArrayListExtra("key", ArrayList(pairs))

            AAddressActivity.appContext.startActivity(intent)
        }
}

Log.d打印非空对的内容./AAddressActivity.appContext其中AAddressActivity是调用Utils.startMap()方法的活动，appContext定义为

companion object{
        lateinit  var appContext: Context
    }

并在onCreate() AAddressActivity AS appContext=this中进行初始化，以允许外部访问AAddressActivity的上下文.
这是接收活动:

class MapActivity : AppCompatActivity(), OnMapReadyCallback {
    lateinit var latLngList: ArrayList<LatLng>
    @RequiresApi(Build.VERSION_CODES.TIRAMISU)
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_map)


        // Error happens here
        latLngList = intent.getParcelableArrayListExtra("key", LatLng::class.java)!!
        Log.d("longMap", latLngList[0].toString())

    }

错误是

    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.androidapplicationproject/com.example.androidapplicationproject.mapUtil.MapActivity}: 
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.Class.isInterface()' on a null object reference

As far as I know, LatLng object implements Parcelable so I shouldn't worry about that. But why is the error happening? How do I fix it.

I just found that if there are only ONE element in the pairs then the MapActivity can successfully receive the parcel, but if there are two or more elements in the list, the exception raises.