RecyclerView itemClickListener in Kotlin [closed]

Answer 1

You don't need to write extension function to ViewHolder or something like this.
Best practice; use Higher-Order Function

MainRecyclerAdapter

class MainRecyclerAdapter(val news: JSONArray, private val itemClickListener: (Int) -> Unit) : RecyclerView.Adapter() {}

Just add a Higher-order func. like itemClickListener and then go to the ViewHolder class. Write this function to your bind function as parameter and set this to itemView Like that :

MainRecyclerAdapter.ViewHolder

 class ViewHolder(val view: View) : RecyclerView.ViewHolder(view) {

        fun bind(newsItem: JSONObject,itemClickListener:(Int)->Unit) {
            //Some Stuff here..

            itemView.setOnClickListener { itemClickListener(adapterPosition) }

        }
    }

Use this method onBindViewHolder

OnBindViewHolder

 override fun onBindViewHolder(holder: MainRecyclerAdapter.ViewHolder, position: Int) {

        holder.bind(news.getJSONObject(position),itemClickListener)
    }

And now you can write your onClick function in any activity or fragments.. Just give as parameter.

Activity or Fragment

val itemOnClick: (Int) -> Unit = { position ->
                newsRecyclerView.adapter!!.notifyDataSetChanged()
                Toast.makeText(this.context,"$position. item clicked.",Toast.LENGTH_SHORT).show()
            }
 newsRecyclerView.adapter = MainRecyclerAdapter(news,itemClickListener = itemOnClick)