Android - Kotlin - object must be declared abstract or implement abstract member

I have set an ItemClickLister for my RecyclerView like this:

ItemClickSupport.addTo(recyclerView!!).setOnItemClickListener(
                    object : ItemClickSupport.OnItemClickListener {
                        override fun onItemClicked(recyclerView: RecyclerView?, position: Int, v: View?) {
                            val row = recyclerView!!.getChildAt(position)
                            val el = row.findViewById(R.id.active_expandablelayout) as ExpandableLayout

                            if (el.isExpanded) {
                                el.collapse()
                            } else {
                                el.expand()
                            }
                        }
                    }
            )

using the ItemClickSupport library which I translated into Kotlin.

I get an error on object (line 2) that says:

object must be declared abstract or implement abstract member.

I'm really new to Kotlin and I couldn't find any solution here on SO either.

Any help is greatly appreciated.

Edit:

Here is my ItemClickSupport.kt:

class ItemClickSupport private constructor(private val mRecyclerView: RecyclerView) {
    private var mOnItemClickListener: OnItemClickListener? = null
    private var mOnItemLongClickListener: OnItemLongClickListener? = null
    private val mOnClickListener = View.OnClickListener { v ->
        if (mOnItemClickListener != null) {
            val holder = mRecyclerView.getChildViewHolder(v)
            mOnItemClickListener!!.onItemClicked(mRecyclerView, holder.adapterPosition, v)
        }
    }
    private val mOnLongClickListener = View.OnLongClickListener { v ->
        if (mOnItemLongClickListener != null) {
            val holder = mRecyclerView.getChildViewHolder(v)
            return@OnLongClickListener mOnItemLongClickListener!!.onItemLongClicked(mRecyclerView, holder.adapterPosition, v)
        }
        false
    }
    private val mAttachListener = object : RecyclerView.OnChildAttachStateChangeListener {
        override fun onChildViewAttachedToWindow(view: View) {
            if (mOnItemClickListener != null) {
                view.setOnClickListener(mOnClickListener)
            }
            if (mOnItemLongClickListener != null) {
                view.setOnLongClickListener(mOnLongClickListener)
            }
        }

        override fun onChildViewDetachedFromWindow(view: View) {

        }
    }

    init {
        mRecyclerView.setTag(R.id.item_click_support, this)
        mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener)
    }

    fun setOnItemClickListener(listener: OnItemClickListener): ItemClickSupport {
        mOnItemClickListener = listener
        return this
    }

    fun setOnItemLongClickListener(listener: OnItemLongClickListener): ItemClickSupport {
        mOnItemLongClickListener = listener
        return this
    }

    private fun detach(view: RecyclerView) {
        view.removeOnChildAttachStateChangeListener(mAttachListener)
        view.setTag(R.id.item_click_support, null)
    }

    interface OnItemClickListener {

        fun onItemClicked(recyclerView: RecyclerView, position: Int, v: View)
    }

    interface OnItemLongClickListener {

        fun onItemLongClicked(recyclerView: RecyclerView, position: Int, v: View): Boolean
    }

    companion object {

        fun addTo(view: RecyclerView): ItemClickSupport {
            var support: ItemClickSupport? = view.getTag(R.id.item_click_support) as ItemClickSupport
            if (support == null) {
                support = ItemClickSupport(view)
            }
            return support
        }

        fun removeFrom(view: RecyclerView): ItemClickSupport {
            val support = view.getTag(R.id.item_click_support) as ItemClickSupport
            support?.detach(view)
            return support
        }
    }
}

This is a screenshot with the whole error and where it happens: