Android - Listener value from Fragment to Adapter?

Question

Im working on an app which has a RecyclerView inside a Fragment. My objective, is to set up onClickItemListener trough the adapter.

However, i encountered a problem setting it up: when i call the adapter, i have to put two parameters, which are the list that i need to apply, and the listener.

If i put this as listener, i get a TypeMismatch error.

What can i use instead of this ?

Fragment.kt

class FragmentItems : Fragment() {
    var itemList = mutableListOf<DataItems>()

    ....

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        ....

        rvTracks.apply {
            setHasFixedSize(true)
            layoutManager = LinearLayoutManager(activity)
            
            //Cant use 'this'!
            adapter = AdapterList(itemList, this)
        }
    }
}

Adapter.kt

class AdapterList(
    var listItems: List<DataItems>,
    var listener: OnItemClickListener
) : RecyclerView.Adapter<AdapterOneColumn.ItemsViewHolder>() {

    inner class ItemsViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView), View.OnClickListener {
        init {
            itemView.setOnClickListener(this)
        }

        override fun onClick(p0: View?) {
            val position : Int = adapterPosition
            if(position != RecyclerView.NO_POSITION) {
                listener.OnItemClick(position)
            }
        }
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ItemsViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_1_column, parent, false)
        return ItemsViewHolder(view)
    }

    override fun getItemCount(): Int {
        return listItems.size
    }

    override fun onBindViewHolder(holder: ItemsViewHolder, position: Int) {
        holder.itemView.apply {
            itemOneColumnTitle.text = listItems[position].stringTitle
            itemOneColumnDescription.text = listItems[position].stringDescription
        }
    }

    interface OnItemClickListener {
        fun OnItemClick(position: Int)
    }
}

Answer 1

if you want to make this work

adapter = AdapterList(itemList, this)

Your class should realize OnItemClickListener that you want to pass, you can fix it by :

class FragmentItems : Fragment(), OnItemClickListener { ...