How to access inner data classes of sealed class from a recyclerView adapter

Question

I'm having trouble setting up my ViewModel data for a chat interface i am building, I have a wide range of different types of data i want to show in a chat layout (RecyclerView). These include: Text,Buttons,Card view carousel...

I have set up a Sealed class which i am hoping will be able to contain all of the data classes needed to display this data, which looks like this atm:

sealed class ChatMessage {
abstract var msgTime: Long?

sealed class Text : ChatMessage() {

    abstract val originator: String
    abstract var content: String

    data class Mine(
            override val originator: String,
            override var msgTime: Long?,
            override var content: String
    ) : Text()

    data class Agent(
            override val originator: String,
            override var msgTime: Long?,
            override var content: String

    ) : Text()

}

sealed class Button : ChatMessage(){

    abstract val title: String
    abstract val actionText: String

    data class General (
            override var title: String,
            override var actionText: String,
            override var msgTime: Long?
            ) : Button()
}
}

In my adapter i am adding it to an arrayList for display:

    var itemsOld: ArrayList<ChatMessage> = ArrayList()

And adding a new item to is as follows:

fun addNewMessage(model: ChatMessage.Text.Mine){

    itemsOld.add(model)

    itemsOld.sortBy { it.msgTime }

   // mRecyclerView!!.smoothScrollToPosition(itemCount - 1)

    MyApplication.appContext!!.runOnUiThread {
        // Stuff that updates the UI
        notifyDataSetChanged()
    }
}

But i cannot access

itemsOld[0].content

or

itemsOld[0].originator

only

itemsOld[0].msgTime

How can i structure the Data classes so i have one parent class which can be implemented by the ArrayList and can hold all data classes i may need to display in the RecyclerView at the same time?

Answer 1

None of those fields are available in ChatMessage model. You need to either cast type to a specific data class or use a when() expression which will do the casting for you. Hope this helps, cheers!