mainactivity

package xyz.goonlinepyb.recycleview;

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

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
private RecyclerView rvHeroes;
    private ArrayList<Hero> list = new ArrayList<>();
    private void showRecyclerGrid(){
        rvHeroes.setLayoutManager(new GridLayoutManager(this,2));
        GridHeroAdapter gridheroadapter = new GridHeroAdapter(list);
        rvHeroes.setAdapter(gridheroadapter);

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

    rvHeroes = findViewById(R.id.rv_heroes);
    rvHeroes.setHasFixedSize(true);

    list.addAll(HeroesData.getListData());
    showRecyclerlist();
    }

    private void showRecyclerlist() {
        rvHeroes.setLayoutManager(new LinearLayoutManager(this));
        ListHeroAdapter listHeroAdapter = new ListHeroAdapter(list);
        rvHeroes.setAdapter(listHeroAdapter);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return super.onCreateOptionsMenu(menu);
    }
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        setMode(item.getItemId());
        return super.onOptionsItemSelected(item);
    }
    public void setMode(int selectedMode) {
        switch (selectedMode) {
            case R.id.action_list:
                showRecyclerlist();
                break;
            case R.id.action_grid:
                showRecyclerGrid();
                break;
            case R.id.action_cardview:
                break;
        }
    }
}