How can i clear my recyclerView data? I have tried a lot of stuff from same type of questions but nothing has helped me

Question

Search Movies Fragment

package com.example.moviemania.views
import android.os.Binder
import android.os.Bundle
import android.text.Editabl
import android.text.TextWatcher
import androidx.fragment.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.EditText
import android.widget.Toast
import androidx.fragment.app.viewModels
import androidx.navigation.fragment.findNavController
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.example.moviemania.adapters.MovieAdapter
import com.example.moviemania.models.Movie
import com.example.moviemania.models.Movies
import com.example.moviemania.R
import com.example.moviemania.databinding.FragmentSearchMoviesBinding
import com.example.moviemania.viewModels.FavViewModel
import com.example.moviemania.viewModels.MovieViewModel


class SearchMoviesFragment : Fragment() {
    private lateinit var recyclerView: RecyclerView
    private val viewModel: MovieViewModel by viewModels()
    private val favViewModel: FavViewModel by viewModels()
    private lateinit var binding:FragmentSearchMoviesBinding

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

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        binding = FragmentSearchMoviesBinding.inflate(layoutInflater,container,false)
        return binding.root
    }

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

        val toolbar = binding.toolbarSearchMoviesFragment
        (activity as MainActivity).setSupportActionBar(toolbar)
        (activity as MainActivity).getSupportActionBar()?.setDisplayShowHomeEnabled(true)
        (activity as MainActivity).getSupportActionBar()?.setDisplayHomeAsUpEnabled(true)
        toolbar.setNavigationOnClickListener {
            (activity as MainActivity).onBackPressed()
        }

        super.onViewCreated(view, savedInstanceState)
        recyclerView = binding.rvSearchMovie
        observeSearchResults()
        setListenersForSearch()
        observeResponseText()

    }

    private fun observeResponseText() = viewModel.responseText.observe(viewLifecycleOwner) {
        //Toast.makeText(this,it.toString(),Toast.LENGTH_SHORT).show()
        Toast.makeText(requireContext(), it, Toast.LENGTH_SHORT).show()
    }

    private fun observeSearchResults() = viewModel.searchReuslt.observe(viewLifecycleOwner) {
        recyclerView.layoutManager = GridLayoutManager(requireContext(), 2)
        val adapter = it?.let { MovieAdapter(it) }
        recyclerView.adapter = adapter
        adapter?.setOnItemClickListener(object : MovieAdapter.onItemClickListener {
            override fun onToggleClick(isFavorite: Boolean, item: Movies) {
                val movie = Movie(
                    movieName = item.original_title,
                    moviePoster = item.poster_path,
                    movieReleaseDate = item.release_date,
                    movieBanner = item.backdrop_path,
                    movieOverview = item.overview
                )
                if (isFavorite) favViewModel.removeMovie(movie) else favViewModel.insertMovie(movie)
            }

            override fun onItemClick(position: Int) {

                val movie = Movie(
                    movieName = it[position].original_title,
                    moviePoster = it[position].poster_path,
                    movieReleaseDate = it[position].release_date,
                    movieBanner = it[position].backdrop_path,
                    movieOverview = it[position].overview,
                    fav = it[position].fav
                )

                val action =
                    SearchMoviesFragmentDirections.actionSearchMoviesFragmentToMovieDetailFragment(
                        it[position].fav,
                        movie,
                        it[position].backdrop_path,
                        it[position].poster_path,
                        it[position].original_title,
                        it[position].release_date,
                        it[position].overview
                    )
                findNavController().navigate(action)
            }
        })
    }

    private fun setListenersForSearch() {

        val etSearchText = view?.findViewById<EditText>(R.id.et_movieSearch)

        etSearchText?.addTextChangedListener(object : TextWatcher {
            override fun afterTextChanged(s: Editable) {
                if (s.length > 3) {
                    viewModel.searchApiCall(s.toString())
                }
            }

            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {

            }

            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
            }
        })
    }


}

MovieAdapter

package com.example.moviemania.adapters

import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView
import com.example.moviemania.extensions.GlideImageExtension.loadImage
import com.example.moviemania.models.Movies
import com.example.moviemania.R
import com.example.moviemania.databinding.MovieListBinding

class MovieAdapter(private val list: List<Movies>) :
    RecyclerView.Adapter<MovieAdapter.MyViewHolder>() {

    private lateinit var myListener: onItemClickListener


    interface onItemClickListener {
        fun onToggleClick(isFavorite: Boolean, item: Movies)
        fun onItemClick(position: Int)
    }

    fun setOnItemClickListener(listener: onItemClickListener) {
        myListener = listener
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
        val binding: MovieListBinding =
            MovieListBinding.inflate(LayoutInflater.from(parent.context), parent, false)
        return MyViewHolder(
            binding,
            myListener
        )
    }


    override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
        val currentItem = list[position]
        holder.bind(currentItem)
    }

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

    inner class MyViewHolder(private val binding: MovieListBinding, listener: onItemClickListener) :
        RecyclerView.ViewHolder(binding.root) {
        init {
            itemView.setOnClickListener {
                with(listener) { onItemClick(adapterPosition) }
            }
        }

        fun bind(item: Movies) {
            item.poster_path?.let { binding.ivMoviePoster.loadImage(it) }
            binding.tvMovieName.text = item.original_title
            binding.movieReleaseDate.text = item.release_date
            binding.favIcon.setImageResource(if (item.fav) R.drawable.redheart else R.drawable.redheart_border)
            binding.favIcon.setOnClickListener {
                myListener.onToggleClick(item.fav, item)
                item.fav = !item.fav
                notifyItemChanged(adapterPosition)
            }
        }
    }

}

I want that when the response result is available meaning that the searched movie does not exist the recyclerview should clear and the screen should be empty. Currently in this scenario it is displaying only the toast but the last successful search data still shows on screen. What i want is that data to be cleared from the recyclerview

Answer 1

when you have to Update RecyclerView on any action, add this to your adapter

public fun setData(private val newList: List<Movies>) {
      lists.clear();
      lists.addAll(newList);
      notifyDataSetChanged();
   }

Than call this method with new data from Activity/Fragment

adapter.updateData(viewModelsWithNewData );