App runs fine without any error but only shows a blank screen after clicking on searchview

Question

I am currently trying to add search view to my recycler view but its not adding.When i run my app without search view it runs completely fine but when i add search view to my app it just shows a blank screen after clicking on searchview icon.

MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import androidx.appcompat.widget.SearchView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private List<Modalclass> item_list;
    private MyDataAdapter myDataAdapter;
    private LinearLayoutManager linearLayoutManager;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        item_list = new ArrayList<>();
        myDataAdapter = new MyDataAdapter(this,item_list);

        linearLayoutManager = new LinearLayoutManager(this);
        recyclerView.setAdapter(myDataAdapter);
        recyclerView.setLayoutManager(linearLayoutManager);



        item_list.add(new Modalclass("123456789",R.drawable.pic1));
        item_list.add(new Modalclass("12345678",R.drawable.pic2));
        item_list.add(new Modalclass("Shivamn",R.drawable.pic1));
        item_list.add(new Modalclass("mmnksksd",R.drawable.pic2));
        item_list.add(new Modalclass("jdsvkjd",R.drawable.pic1));
        item_list.add(new Modalclass("sdvfdv",R.drawable.pic2));
        item_list.add(new Modalclass("retw",R.drawable.pic1));
        item_list.add(new Modalclass("xcvsdsfv",R.drawable.pic2));
        item_list.add(new Modalclass("dfgsd",R.drawable.pic1));
        item_list.add(new Modalclass("dgsdg",R.drawable.pic2));
        item_list.add(new Modalclass("dsgdfgsd",R.drawable.pic1));
        item_list.add(new Modalclass("ewete",R.drawable.pic2));
        item_list.add(new Modalclass("vferthe",R.drawable.pic1));
        item_list.add(new Modalclass("gfdnhytj",R.drawable.pic2));
        item_list.add(new Modalclass("nfhjtyj",R.drawable.pic1));
        item_list.add(new Modalclass("gfnthtr",R.drawable.pic2));
        item_list.add(new Modalclass("dsffgrtg",R.drawable.pic1));
        item_list.add(new Modalclass("sdfgrtg",R.drawable.pic2));


    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu){
        getMenuInflater().inflate(R.menu.search_view,menu);
        MenuItem searchItem=menu.findItem(R.id.search_view);
        SearchView searchView= (SearchView) searchItem.getActionView();
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                myDataAdapter.getFilter().filter(newText);
                return false;
            }
        });
        return true;

    }
}

activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">


    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginStart="1dp"
        android:layout_marginTop="1dp"
        android:layout_marginEnd="1dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

MyDataAdapter.java

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.ImageView;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

public class MyDataAdapter extends RecyclerView.Adapter<MyDataAdapter.MyViewHolder> implements Filterable {

    private Context context;
    private List<Modalclass> item_list;
    private List<Modalclass> item_list_full;

    public MyDataAdapter(Context context, List<Modalclass> item_list) {
        this.context = context;
        this.item_list = item_list;
        this.item_list_full = new ArrayList<>(item_list);
    }

    @NonNull
    @Override
    public MyDataAdapter.MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_item,parent,false);
        return new MyViewHolder(view);

    }

    @Override
    public void onBindViewHolder(@NonNull MyDataAdapter.MyViewHolder holder, int position) {

        final Modalclass modalclass = item_list.get(position);

        holder.textView.setText(item_list.get(position).getName());
        holder.imageView.setImageResource(item_list.get(position).getImgresource());

    }

    @Override
    public int getItemCount() {
        return item_list.size();
    }



    public class MyViewHolder extends RecyclerView.ViewHolder{
        TextView textView;
        ImageView imageView;
        View mView;

        public MyViewHolder(@NonNull View itemView) {
            super(itemView);
            textView = itemView.findViewById(R.id.t1);
            imageView = itemView.findViewById(R.id.i1);
            mView=itemView;


        }
    }


    @Override
    public Filter getFilter() {
        return DataFilter;
    }

    private Filter DataFilter= new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            List<Modalclass> filteredList = new ArrayList<>();
            if (constraint==null || constraint.length()==0 ){
                filteredList.addAll(item_list_full);
            }
            else {
                String filter=constraint.toString().toLowerCase().trim();
                for (Modalclass dataitem:item_list_full){
                    if (dataitem.getName().toLowerCase().contains(filter)){
                        filteredList.add(dataitem);
                    }

                }
            }
            FilterResults results=new FilterResults();
            results.values=filteredList;
            return results;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            item_list.clear();
            item_list.addAll((Collection<? extends Modalclass>) results.values);
            notifyDataSetChanged();

        }
    };
}

Modalclass.java

    class Modalclass {
    String Name;
    int imgresource;

    public Modalclass(String name, int imgresource) {
        Name = name;
        this.imgresource = imgresource;
    }

    public String getName() {
        return Name;
    }

    public void setName(String name) {
        Name = name;
    }

    public int getImgresource() {
        return imgresource;
    }

    public void setImgresource(int imgresource) {
        this.imgresource = imgresource;
    }
}

search_view.xml

    <?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item android:id="@+id/search_view"
        android:icon="@drawable/ic_search_black_24dp"
        android:title="Search"
        app:showAsAction="ifRoom|collapseActionView"
        app:actionViewClass="androidx.appcompat.widget.SearchView"/>





</menu>

recycler_item.xml

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="4dp"
    android:layout_marginBottom="8dp">

    <TextView
        android:id="@+id/t1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:height="70dp"
        android:fontFamily="casual"
        android:gravity="center"
        android:text="TextView"
        android:textColor="#3D3636"
        android:textSize="20sp"
        android:textStyle="bold" />

    <ImageView
        android:id="@+id/i1"
        android:layout_width="match_parent"
        android:layout_height="70dp"
        android:layout_weight="2"
        android:scaleType="fitXY"
        app:srcCompat="@mipmap/ic_launcher" />
</LinearLayout>

Answer 1

In the MainActivity, try to replace

import android.widget.SearchView;

with

import androidx.appcompat.widget.SearchView;

Answer 2

This is because your are adding items to list after you are passing it to the adapter. Please move these lines up in your code.

    item_list.add(new Modalclass("123456789",R.drawable.pic1));
    item_list.add(new Modalclass("12345678",R.drawable.pic2));
    item_list.add(new Modalclass("Shivamn",R.drawable.pic1));
    item_list.add(new Modalclass("mmnksksd",R.drawable.pic2));
    item_list.add(new Modalclass("jdsvkjd",R.drawable.pic1));
    item_list.add(new Modalclass("sdvfdv",R.drawable.pic2));
    item_list.add(new Modalclass("retw",R.drawable.pic1));
    item_list.add(new Modalclass("xcvsdsfv",R.drawable.pic2));
    item_list.add(new Modalclass("dfgsd",R.drawable.pic1));
    item_list.add(new Modalclass("dgsdg",R.drawable.pic2));
    item_list.add(new Modalclass("dsgdfgsd",R.drawable.pic1));
    item_list.add(new Modalclass("ewete",R.drawable.pic2));
    item_list.add(new Modalclass("vferthe",R.drawable.pic1));
    item_list.add(new Modalclass("gfdnhytj",R.drawable.pic2));
    item_list.add(new Modalclass("nfhjtyj",R.drawable.pic1));
    item_list.add(new Modalclass("gfnthtr",R.drawable.pic2));
    item_list.add(new Modalclass("dsffgrtg",R.drawable.pic1));
    item_list.add(new Modalclass("sdfgrtg",R.drawable.pic2));

move them before this line

    myDataAdapter = new MyDataAdapter(this,item_list);