I think there is too much Activity

Suppose that I have an application that stores information about the objects of my city. I have a MainActivity , which contains a HomeFragment , which in turn contains a RecyclerView . This is a list of object categories (Shops, shopping centers, etc.). When I click on each item RecyclerView I get on a new Activity , which contains a list of CardView (these are already items of a specific category). And, accordingly, when I click on each CardView element CardView I get on a new Activity , which contains a description of a specific object. I have already begun to make it so that when I click on each item RecyclerView , for example, I create a new Activity and switch to it. And so on. The result is a lot of Activity . But after all, you can do, for example, a HomeFragment with a list of categories, one Activity , which contains elements of a specific category and one Activity , which contains a description of a specific object and only display the necessary data in them. The question is how to do it.

HomeFragment Code:

 public class HomeFragment extends Fragment { private final String placeNames[] = { "Категория 1", "Категория 2", "Категория 3", "Категория 4", "Категория 5", }; private final String imageUrls[] = { "https://cat1.jpg", "httsp://cat2.jpg", "https://cat3.jpg", "https://cat4.jpg", "https://cat5.jpg", }; public HomeFragment() {} @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_home, container, false); RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.recycler_view); recyclerView.setHasFixedSize(true); RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity()); recyclerView.setLayoutManager(layoutManager); // при нажатии на каждый элемент создаю новую Активити recyclerView.addOnItemTouchListener( new RecyclerItemClickListener(getActivity(), new RecyclerItemClickListener.OnItemClickListener() { @Override public void onItemClick(View view, int position) { switch (position) { case 0: getActivity().startActivity(new Intent(getActivity(), ShopsActivity.class)); break; case 1: getActivity().startActivity(new Intent(getActivity(), ShopCentersActivity.class)); break; case 2: getActivity().startActivity(new Intent(getActivity(), FunActivity.class)); break; case 3: getActivity().startActivity(new Intent(getActivity(), NightLifeActivity.class)); break; case 4: getActivity().startActivity(new Intent(getActivity(), BeautyAndHealthActivity.class)); break; case 5: getActivity().startActivity(new Intent(getActivity(), SportActivity.class)); break; default: break; } } }) ); ArrayList placeItems = prepareData(); DataAdapter adapter = new DataAdapter(placeItems, getActivity()); recyclerView.setAdapter(adapter); return view; } private ArrayList prepareData() { ArrayList placeItemList = new ArrayList<>(); for (int i = 0; i < placeNames.length; i++) { PlaceItem itemPlace = new PlaceItem(); itemPlace.setPlaceName(placeNames[i]); itemPlace.setImageUrl(imageUrls[i]); placeItemList.add(itemPlace); } return placeItemList; } } 

Code specific category ShopsActivity :

 public class ShopsActivity extends AppCompatActivity { private ShopsAdapter adapter; private List<ConcreteObject> objectList; @SuppressLint("PrivateResource") @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_shops); Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); if (toolbar != null) { toolbar.setNavigationIcon(R.drawable.abc_ic_ab_back_mtrl_am_alpha); toolbar.setNavigationOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { onBackPressed(); } }); } RecyclerView recyclerView = (RecyclerView) findViewById(R.id.shops_recycler_view); objectList = new ArrayList<>(); adapter = new ShopsAdapter(this, objectList); RecyclerView.LayoutManager layoutManager = new GridLayoutManager(this, 2); if (recyclerView != null) { recyclerView.setLayoutManager(layoutManager); recyclerView.addItemDecoration(new GridSpacingItemDecoration(2, dpToPx(10), true)); recyclerView.setItemAnimator(new DefaultItemAnimator()); recyclerView.setAdapter(adapter); // тут я снова создаю новые Активити и перехожу на них recyclerView.addOnItemTouchListener(new RecyclerTouchListener(getApplicationContext(), recyclerView, new RecyclerTouchListener.ClickListener() { @Override public void onClick(View view, int position) { switch (position) { case 0: startActivity(new Intent(ShopsActivity.this, OneShop.class)); break; case 1: startActivity(new Intent(ShopsActivity.this, TwoShop.class)); break; case 2: startActivity(new Intent(ShopsActivity.this, ThreeShop.class)); break; case 3: startActivity(new Intent(ShopsActivity.this, FourShop.class)); break; case 4: startActivity(new Intent(ShopsActivity.this, FiveShop.class)); break; case 5: startActivity(new Intent(ShopsActivity.this, SixShop.class)); break; case 6: startActivity(new Intent(ShopsActivity.this, SevenShop.class)); break; case 7: startActivity(new Intent(ShopsActivity.this, Eight.class)); break; default: break; } } @Override public void onLongClick(View view, int position) { } })); } prepareObjects(); Glide.with(this) .load(R.drawable.cover_backdrop) .into((ImageView) findViewById(R.id.backdrop)); } @Override protected void prepareObjects() { objectList.add(new ConcreteObject("Oneshop", 3.9, R.drawable.one)); objectList.add(new ConcreteObject("TwoShop", 3.5, R.drawable.two)); objectList.add(new ConcreteObject("ThreeShop", 3.5, R.drawable.three)); objectList.add(new ConcreteObject("FourShop", 3.5, R.drawable.four)); ... adapter.notifyDataSetChanged(); } } 

The code for a particular ConcreteOneActivity object:

 public class ConcreteOneActivity extends StartConfig { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_concrete_one); setToolbar(R.id.toolbar_concrete_one_toolbar); setCollapsingToolbar("ConcreteOne", R.id.concrete_one_collapsing_toolbar); CustomPagerAdapter adapter = new CustomPagerAdapter(this) { @Override public Object instantiateItem(ViewGroup collection, int position) { LayoutInflater inflater = LayoutInflater.from(context); View view = null; switch (position) { case 0: view = inflater.inflate(R.layout.concrete_one_information, collection, false); break; case 1: view = inflater.inflate(R.layout.concrete_one_location, collection, false); break; case 2: view = inflater.inflate(R.layout.map_fragment, collection, false); SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() .findFragmentById(R.id.map); mapFragment.getMapAsync(this); break; } collection.addView(view); return view; } @Override public void onMapReady(GoogleMap googleMap) { mMap = googleMap; LatLng concreteOne = new LatLng(1, 1); mMap.addMarker(new MarkerOptions().position(concreteOne).title("ConcreteOne"); mMap.moveCamera(CameraUpdateFactory.newLatLng(concreteOne)); } }; setViewPager(adapter); } }