问getParcelableArrayListExtra导致将不同的类型设置为变量。

EN

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

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

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)
  }   
}

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)
      }
    }
  }
}