RecyclerView not showing in Layout

Question

I want to achieve a layout as shown in the Android Studio preview (left). However if executed in the emulator, only the button is visible and the RecyclerView is not visible/populated (right).

The XML code:

However if the RecyclerView is alone in the fragment the list is populated (but of course the action button is not showing). Code see below. And yes, my list which should be shown is not empty.

I have already tried using RelativeLayout and FrameLayout, but I still get the same result. The same behavior occurs if I use e.g. a TextView instead of the action button.

--- Requested additional info ---

Adapter class (automatically generated by Android Studio, template):

class MyItemRecyclerViewAdapter(
    private val mValues: List,
    private val mListener: OnListFragmentInteractionListener?
) : RecyclerView.Adapter() {

    private val mOnClickListener: View.OnClickListener

    init {
        mOnClickListener = View.OnClickListener { v ->
            val item = v.tag as DummyItem
            // Notify the active callbacks interface (the activity, if the fragment is attached to
            // one) that an item has been selected.
            mListener?.onListFragmentInteraction(item)
        }
    }

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

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val item = mValues[position]
        holder.mIdView.text = item.id
        holder.mContentView.text = item.content

        with(holder.mView) {
            tag = item
            setOnClickListener(mOnClickListener)
        }
    }

    override fun getItemCount(): Int = mValues.size

    inner class ViewHolder(val mView: View) : RecyclerView.ViewHolder(mView) {
        val mIdView: TextView = mView.item_number
        val mContentView: TextView = mView.content

        override fun toString(): String {
            return super.toString() + " '" + mContentView.text + "'"
        }
    }
}

List fragment (automatically generated by Android Studio, template):

class ItemFragment : Fragment() {

    // TODO: Customize parameters
    private var columnCount = 1

    private var listener: OnListFragmentInteractionListener? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        arguments?.let {
            columnCount = it.getInt(ARG_COLUMN_COUNT)
        }
    }

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val view = inflater.inflate(R.layout.fragment_item_list, container, false)

        // Set the adapter
        if (view is RecyclerView) {
            with(view) {
                layoutManager = when {
                    columnCount <= 1 -> LinearLayoutManager(context)
                    else -> GridLayoutManager(context, columnCount)
                }
                adapter = MyItemRecyclerViewAdapter(DummyContent.ITEMS, listener)
            }
        }
        return view
    }

    override fun onAttach(context: Context) {
        super.onAttach(context)
        if (context is OnListFragmentInteractionListener) {
            listener = context
        } else {
            throw RuntimeException(context.toString() + " must implement OnListFragmentInteractionListener")
        }
    }

    override fun onDetach() {
        super.onDetach()
        listener = null
    }

    /**
     * This interface must be implemented by activities that contain this
     * fragment to allow an interaction in this fragment to be communicated
     * to the activity and potentially other fragments contained in that
     * activity.
     *
     *
     * See the Android Training lesson
     * [Communicating with Other Fragments](http://developer.android.com/training/basics/fragments/communicating.html)
     * for more information.
     */
    interface OnListFragmentInteractionListener {
        // TODO: Update argument type and name
        fun onListFragmentInteraction(item: DummyItem?)
    }

    companion object {

        // TODO: Customize parameter argument names
        const val ARG_COLUMN_COUNT = "column-count"

        // TODO: Customize parameter initialization
        @JvmStatic
        fun newInstance(columnCount: Int) =
            ItemFragment().apply {
                arguments = Bundle().apply {
                    putInt(ARG_COLUMN_COUNT, columnCount)
                }
            }
    }
}

Rafsanjani · Accepted Answer

Try this for your layout

Inside ItemFragment.kt replace onCreateView with

override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {

return inflater.inflate(R.layout.fragment_item_list, container, false)
}

After that go ahead and implement onViewCreated as such

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    with(list) {
        layoutManager = when {
            columnCount <= 1 -> LinearLayoutManager(requireContext())
            else -> GridLayoutManager(requireContext(), columnCount)
        }
        adapter = MyItemRecyclerViewAdapter(DummyContent.ITEMS)
    }
}

This should fix your problem because the AS template is assuming that the rootview will be a RecyclerView and is treating the whole layout as such.

RecyclerView not showing in Layout

Answers (1)

Related Questions