ListView showing wrong item name after filtering

I am new in android apps development. I am learning coding from YouTube. Below is my customListView code containing OnItemClick Listener and Action Bar searcView. Everything is okay but the problem is after filtering. I am not getting the right item name on Toast after filtering. it always takes data from my array source I have written in the ArrayItemlist. I know there is a similar question here but I sorry not to implement those in the same way. I have searched everywhere i can but didn't get the right way I wanted. At last, I have registered at StackOverflow and this is my first post. Please help me. Maybe the solution is about 3 or 4 lines. Please instruct me on the coding.

   public class MainActivity extends AppCompatActivity {
   private ListView listView;
   ArrayList<allCountry> items=new ArrayList<>();  //item are countries
   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

       listView=findViewById(R.id.listViewId);


       ArrayList<allCountry> detail= new ArrayList<>();  //detail are the short description after item.

       items.add(new allCountry("Bangladesh","Is My Motherland",R.drawable.bangladesh));
       items.add(new allCountry("India","The Seven Wonder",R.drawable.india));
       items.add(new allCountry("Pakistan","The Traitor 71",R.drawable.pakistan));
       items.add(new allCountry("Afghanistha","The Ghost Cricket Team",R.drawable.afghanistan));
       items.add(new allCountry("Sri Lanka","The Mountain",R.drawable.srilanka));
       items.add(new allCountry("Bhutan","No Smoking Zone",R.drawable.bhutan));
       items.add(new allCountry("Nepal","The Buddhist",R.drawable.nepal));
       items.add(new allCountry("Maldivs","Oh! Island",R.drawable.maldives));
       items.add(new allCountry("Argentina","The Hero Maradona",R.drawable.argentina));
       items.add(new allCountry("Brazil","The Hero Pele",R.drawable.brazil));
       items.add(new allCountry("Canada","The Hero Trudo",R.drawable.canada));
       items.add(new allCountry("Mexico","The Beautiful City",R.drawable.mexico));
       items.add(new allCountry("Uganda","To be Described",R.drawable.uganda));
       listView.setAdapter(new customAdapter(MainActivity.this,R.layout.my_list_item,items,detail));

       listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
           @Override
           public void onItemClick(AdapterView<?> adapterView, View countryNames, int position, long l) {
       
      // Here is the problem. it needs update position
    Toast.makeText(MainActivity.this,items.get(position).countryNames,Toast.LENGTH_SHORT).show();


           }
       });

      }
  
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
       getMenuInflater().inflate(R.menu.my_menu,menu);
       MenuItem menuItem=menu.findItem(R.id.SearchMenuId);
       SearchView searchView= (SearchView) menuItem.getActionView();

       searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {  
           @Override
           public boolean onQueryTextSubmit(String s) {
               return false;
           }

           @Override
           public boolean onQueryTextChange(String newText) {
               ArrayList<allCountry> result=new ArrayList<>();
               for (allCountry x: items){
                   if (x.countryNames.toLowerCase().trim().contains(newText)|| 
                        x.countryNames.toUpperCase().trim().contains(newText)){
                       result.add(x);


                   }
               }
               (  (customAdapter) listView.getAdapter()).update(result);

               return false;
           }

         });

          return super.onCreateOptionsMenu(menu);
       }

        }

///CustomAdapter.java

    public class customAdapter extends ArrayAdapter {
    ArrayList<allCountry>items;
    ArrayList<allCountry> detail;
    public  customAdapter (Context context, int layout, ArrayList<allCountry> items,ArrayList<allCountry> 
                            detail){
        super(context,layout);
        this.items=items;
        this.detail=detail;
    }
    public void update(ArrayList<allCountry> result){
        items=new ArrayList<>();
        items.addAll(result);
        notifyDataSetChanged();
    }
    public class ViewHolder{
        TextView textView;

        ImageView imageView;
        TextView textView1;
    }

    @Override
    public int getCount() {
        return items.size();

    }

    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
        View row;
        row=convertView;
        ViewHolder viewHolder;
        if (convertView==null){
            row= LayoutInflater.from(getContext()).inflate(R.layout.my_list_item,parent,false);
            viewHolder=new ViewHolder();
            viewHolder.imageView=row.findViewById(R.id.imageViewId);
            viewHolder.textView=row.findViewById(R.id.countryNamesTextViewId);
            viewHolder.textView1=row.findViewById(R.id.showDetailsTextViewId);
            row.setTag(viewHolder);

        }
        else {
            viewHolder= (ViewHolder) row.getTag();
        }
        viewHolder.imageView.setImageResource(items.get(position).flags);
        viewHolder.textView.setText(items.get(position).countryNames);
        viewHolder.textView1.setText(items.get(position).showDetails);


        return row;
      }
     }

///allcountry.java

    public class allCountry {
    String countryNames;
    String showDetails;
    int flags;

    public allCountry(String countryNames, String showDetails,int flags){

        this.countryNames=countryNames;
        this.flags=flags;
        this.showDetails=showDetails;
    }
   }

One way would be to put inside getView:

row.setOnClickListener(.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
               Toast.makeText(view.getContext(),items.get(position).countryNames,Toast.LENGTH_SHORT).show();

        }
    });

and remove OnItemClickListener