नेविगेशन कॉम्पोनेंट पर माइग्रेट करें

class ProductListFragment : Fragment() {
    // Leave empty for now.
}

public class ProductListFragment extends Fragment {
    // Leave empty for now.
}

class ProductListActivity : AppCompatActivity() {

    // Views and/or ViewDataBinding references, Adapters...
    private lateinit var productAdapter: ProductAdapter
    private lateinit var binding: ProductListActivityBinding

    ...

    // ViewModels, System Services, other Dependencies...
    private val viewModel: ProductListViewModel by viewModels()

    ...

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

        // View initialization logic
        DataBindingUtil.setContentView(this, R.layout.product_list_activity)

        // Post view initialization logic
        // Connect adapters
        productAdapter = ProductAdapter(productClickCallback)
        binding.productsList.setAdapter(productAdapter)

        // Initialize view properties, set click listeners, etc.
        binding.productsSearchBtn.setOnClickListener {...}

        // Subscribe to state
        viewModel.products.observe(this, Observer { myProducts ->
            ...
        })

        // ...and so on
    }
   ...
}

public class ProductListActivity extends AppCompatActivity {

    // Views and/or ViewDataBinding references, adapters...
    private ProductAdapter productAdapter;
    private ProductListActivityBinding binding;

    ...

    // ViewModels, system services, other dependencies...
    private ProductListViewModel viewModel;

    ...

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // View initialization logic
        DataBindingUtil.setContentView(this, R.layout.product_list_activity);

        // Post view initialization logic
        // Connect adapters
        productAdapter = new ProductAdapter(productClickCallback);
        binding.productsList.setAdapter(productAdapter);

        // Initialize ViewModels and other dependencies
        ProductListViewModel viewModel = new ViewModelProvider(this).get(ProductListViewModel.java);

        // Initialize view properties, set click listeners, etc.
        binding.productsSearchBtn.setOnClickListener(v -> { ... });

        // Subscribe to state
        viewModel.getProducts().observe(this, myProducts ->
            ...
       );

       // ...and so on
   }

    // Provided to ProductAdapter in ProductListActivity snippet.
    private val productClickCallback = ProductClickCallback { product ->
        show(product)
    }

    fun show(product: Product) {
        val intent = Intent(this, ProductActivity::class.java)
        intent.putExtra(ProductActivity.KEY_PRODUCT_ID, product.id)
        startActivity(intent)
    }

// Provided to ProductAdapter in ProductListActivity snippet.
private ProductClickCallback productClickCallback = this::show;

private void show(Product product) {
    Intent intent = new Intent(this, ProductActivity.class);
    intent.putExtra(ProductActivity.KEY_PRODUCT_ID, product.getId());
    startActivity(intent);
}

class ProductListFragment : Fragment() {

    private lateinit var binding: ProductListFragmentBinding
    private val viewModel: ProductListViewModel by viewModels()

     // View initialization logic
    override fun onCreateView(inflater: LayoutInflater,
            container: ViewGroup?,
            savedInstanceState: Bundle?): View? {
        binding = DataBindingUtil.inflate(
                inflater,
                R.layout.product_list,
                container,
                false
        )
        return binding.root
    }

    // Post view initialization logic
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        // Connect adapters
        productAdapter = ProductAdapter(productClickCallback)
        binding.productsList.setAdapter(productAdapter)

        // Initialize view properties, set click listeners, etc.
        binding.productsSearchBtn.setOnClickListener {...}

        // Subscribe to state
        viewModel.products.observe(this, Observer { myProducts ->
            ...
        })

        // ...and so on
    }

    // Provided to ProductAdapter
    private val productClickCallback = ProductClickCallback { product ->
        if (lifecycle.currentState.isAtLeast(Lifecycle.State.STARTED)) {
            (requireActivity() as ProductListActivity).show(product)
        }
    }
    ...
}

public class ProductListFragment extends Fragment {

    private ProductAdapter productAdapter;
    private ProductListFragmentBinding binding;

    // View initialization logic
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater,
            @Nullable ViewGroup container,
            @Nullable Bundle savedInstanceState) {
        binding = DataBindingUtil.inflate(
                inflater,
                R.layout.product_list_fragment,
                container,
                false);
        return binding.getRoot();
    }

    // Post view initialization logic
    @Override
    public void onViewCreated(@NonNull View view,
            @Nullable Bundle savedInstanceState) {

        // Connect adapters
        binding.productsList.setAdapter(productAdapter);

        // Initialize ViewModels and other dependencies
        ProductListViewModel viewModel = new ViewModelProvider(this)
                .get(ProductListViewModel.class);

        // Initialize view properties, set click listeners, etc.
        binding.productsSearchBtn.setOnClickListener(...)

        // Subscribe to state
        viewModel.getProducts().observe(this, myProducts -> {
            ...
       });

       // ...and so on

    // Provided to ProductAdapter
    private ProductClickCallback productClickCallback = new ProductClickCallback() {
        @Override
        public void onClick(Product product) {
            if (getLifecycle().getCurrentState().isAtLeast(Lifecycle.State.STARTED)) {
                ((ProductListActivity) requireActivity()).show(product);
            }
        }
    };
    ...
}

class ProductListActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.product_list_host)
    }

    fun show(product: Product) {
        val intent = Intent(this, ProductActivity::class.java)
        intent.putExtra(ProductActivity.KEY_PRODUCT_ID, product.id)
        startActivity(intent)
    }
}

public class ProductListActivity extends AppCompatActivity {

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

    public void show(Product product) {
        Intent intent = new Intent(this, ProductActivity.class);
        intent.putExtra(ProductActivity.KEY_PRODUCT_ID, product.getId());
        startActivity(intent);
    }
}

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.product_list_host)

    if (savedInstanceState == null) {
        val fragment = ProductListFragment()
        supportFragmentManager
                .beginTransaction()
                .add(R.id.main_content, fragment)
                .commit()
    }
}

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

    if (savedInstanceState == null) {
        ProductListFragment fragment = new ProductListFragment();
        getSupportFragmentManager()
                .beginTransaction()
                .add(R.id.main_content, fragment)
                .commit();
    }
}

...

if (savedInstanceState == null) {
    val fragment = ProductDetailsFragment()

    // Intent extras and Fragment Args are both of type android.os.Bundle.
    fragment.arguments = intent.extras

    supportFragmentManager
            .beginTransaction()
            .add(R.id.main_content, fragment)
            .commit()
}

...

...

if (savedInstanceState == null) {
    ProductDetailsFragment fragment = new ProductDetailsFragment();

    // Intent extras and fragment Args are both of type android.os.Bundle.
    fragment.setArguments(getIntent().getExtras());

    getSupportFragmentManager()
            .beginTransaction()
            .add(R.id.main_content, fragment)
            .commit();
}

...

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Logic to load the starting destination
        //  when the Activity is first created
        if (savedInstanceState == null) {
            val fragment = ProductListFragment()
            supportFragmentManager.beginTransaction()
                    .add(R.id.fragment_container, fragment, ProductListFragment.TAG)
                    .commit()
        }
    }

    // Logic to navigate the user to another destination.
    // This may include logic to initialize and set arguments on the destination
    // fragment or even transition animations between the fragments (not shown here).
    fun navigateToProductDetail(productId: String) {
        val fragment = new ProductDetailsFragment()
        val args = Bundle().apply {
            putInt(KEY_PRODUCT_ID, productId)
        }
        fragment.arguments = args

        supportFragmentManager.beginTransaction()
                .addToBackStack(ProductDetailsFragment.TAG)
                .replace(R.id.fragment_container, fragment, ProductDetailsFragment.TAG)
                .commit()
    }
}

public class MainActivity extends AppCompatActivity {

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

        // Logic to load the starting destination when the activity is first created.
        if (savedInstanceState == null) {
            val fragment = ProductListFragment()
            supportFragmentManager.beginTransaction()
                    .add(R.id.fragment_container, fragment, ProductListFragment.TAG)
                    .commit();
        }
    }

    // Logic to navigate the user to another destination.
    // This may include logic to initialize and set arguments on the destination
    // fragment or even transition animations between the fragments (not shown here).
    public void navigateToProductDetail(String productId) {
        Fragment fragment = new ProductDetailsFragment();
        Bundle args = new Bundle();
        args.putInt(KEY_PRODUCT_ID, productId);
        fragment.setArguments(args);

        getSupportFragmentManager().beginTransaction()
                .addToBackStack(ProductDetailsFragment.TAG)
                .replace(R.id.fragment_container, fragment, ProductDetailsFragment.TAG)
                .commit();
    }
}

class ProductListFragment : Fragment() {
    ...
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        // In this example a callback is passed to respond to an item clicked
        //  in a RecyclerView
        productAdapter = ProductAdapter(productClickCallback)
        binding.productsList.setAdapter(productAdapter)
    }
    ...

    // The callback makes the call to the activity to make the transition.
    private val productClickCallback = ProductClickCallback { product ->
            (requireActivity() as MainActivity).navigateToProductDetail(product.id)
    }
}

public class ProductListFragment extends Fragment  {
    ...
    @Override
    public void onViewCreated(@NonNull View view,
            @Nullable Bundle savedInstanceState) {
    // In this example a callback is passed to respond to an item clicked in a RecyclerView
        productAdapter = new ProductAdapter(productClickCallback);
        binding.productsList.setAdapter(productAdapter);
    }
    ...

    // The callback makes the call to the activity to make the transition.
    private ProductClickCallback productClickCallback = product -> (
        ((MainActivity) requireActivity()).navigateToProductDetail(product.getId())
    );
}

class MainActivity : AppCompatActivity() {

    // No need to load the start destination, handled automatically by the Navigation component
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
    }
}

public class MainActivity extends AppCompatActivity {

    // No need to load the start destination, handled automatically by the Navigation component
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

class ProductListFragment : Fragment() {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        // In this example a callback is passed to respond to an item clicked in a RecyclerView
        productAdapter = ProductAdapter(productClickCallback)
        binding.productsList.setAdapter(productAdapter)
    }
    ...

    // The callback makes the call to the NavController to make the transition.
    private val productClickCallback = ProductClickCallback { product ->
        val directions = ProductListDirections.navigateToProductDetail(product.id)
        findNavController().navigate(directions)
    }
}

public class ProductListFragment extends Fragment  {
    ...
    @Override
    public void onViewCreated(@NonNull View view,
            @Nullable Bundle savedInstanceState) {
        // In this example a callback is passed to respond to an item clicked in a RecyclerView
        productAdapter = new ProductAdapter(productClickCallback);
        binding.productsList.setAdapter(productAdapter);
    }
    ...

    // The callback makes the call to the activity to make the transition.
    private ProductClickCallback productClickCallback = product -> {
        ProductListDirections.ViewProductDetails directions =
                ProductListDirections.navigateToProductDetail(product.getId());
        NavHostFragment.findNavController(this).navigate(directions);
    };
}

class MainActivity : AppCompatActivity(),
    NavigationView.OnNavigationItemSelectedListener {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val toolbar: Toolbar = findViewById(R.id.toolbar)
        setSupportActionBar(toolbar)

        val drawerLayout: DrawerLayout = findViewById(R.id.drawer_layout)
        val navView: NavigationView = findViewById(R.id.nav_view)
        val toggle = ActionBarDrawerToggle(
                this,
                drawerLayout,
                toolbar,
                R.string.navigation_drawer_open, 
                R.string.navigation_drawer_close
        )
        drawerLayout.addDrawerListener(toggle)
        toggle.syncState()

        navView.setNavigationItemSelectedListener(this)
    }

    override fun onBackPressed() {
        val drawerLayout: DrawerLayout = findViewById(R.id.drawer_layout)
        if (drawerLayout.isDrawerOpen(GravityCompat.START)) {
            drawerLayout.closeDrawer(GravityCompat.START)
        } else {
            super.onBackPressed()
        }
    }

    override fun onNavigationItemSelected(item: MenuItem): Boolean {
        // Handle navigation view item clicks here.
        when (item.itemId) {
            R.id.home -> {
                val homeFragment = HomeFragment()
                show(homeFragment)
            }
            R.id.gallery -> {
                val galleryFragment = GalleryFragment()
                show(galleryFragment)
            }
            R.id.slide_show -> {
                val slideShowFragment = SlideShowFragment()
                show(slideShowFragment)
            }
            R.id.tools -> {
                val toolsFragment = ToolsFragment()
                show(toolsFragment)
            }
        }
        val drawerLayout: DrawerLayout = findViewById(R.id.drawer_layout)
        drawerLayout.closeDrawer(GravityCompat.START)
        return true
    }
}

private fun show(fragment: Fragment) {

    val drawerLayout = drawer_layout as DrawerLayout
    val fragmentManager = supportFragmentManager

    fragmentManager
            .beginTransaction()
            .replace(R.id.main_content, fragment)
            .commit()

    drawerLayout.closeDrawer(GravityCompat.START)
}

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

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

        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        NavigationView navigationView = findViewById(R.id.nav_view);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this,
                drawer,
                toolbar,
                R.string.navigation_drawer_open,
                R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);
        toggle.syncState();

        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.home) {
            Fragment homeFragment = new HomeFragment();
            show(homeFragment);
        } else if (id == R.id.gallery) {
            Fragment galleryFragment = new GalleryFragment();
            show(galleryFragment);
        } else if (id == R.id.slide_show) {
            Fragment slideShowFragment = new SlideShowFragment();
            show(slideShowFragment);
        } else if (id == R.id.tools) {
            Fragment toolsFragment = new ToolsFragment();
            show(toolsFragment);
        }

        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }

    private void show(Fragment fragment) {

        DrawerLayout drawerLayout = findViewById(R.id.drawer_layout);
        FragmentManager fragmentManager = getSupportFragmentManager();

        fragmentManager
                .beginTransaction()
                .replace(R.id.main_content, fragment)
                .commit();

        drawerLayout.closeDrawer(GravityCompat.START);
    }
}

class MainActivity : AppCompatActivity()  {

    val drawerLayout by lazy { findViewById<DrawerLayout>(R.id.drawer_layout) }
    val navController by lazy {
      (supportFragmentManager.findFragmentById(R.id.main_content) as NavHostFragment).navController
    }
    val navigationView by lazy { findViewById<NavigationView>(R.id.nav_view) }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val toolbar = findViewById<Toolbar>(R.id.toolbar)
        setSupportActionBar(toolbar)

        // Show and Manage the Drawer and Back Icon
        setupActionBarWithNavController(navController, drawerLayout)

        // Handle Navigation item clicks
        // This works with no further action on your part if the menu and destination id’s match.
        navigationView.setupWithNavController(navController)

    }

    override fun onSupportNavigateUp(): Boolean {
        // Allows NavigationUI to support proper up navigation or the drawer layout
        // drawer menu, depending on the situation
        return navController.navigateUp(drawerLayout)
    }
}

public class MainActivity extends AppCompatActivity {

    private DrawerLayout drawerLayout;
    private NavController navController;
    private NavigationView navigationView;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        drawerLayout = findViewById(R.id.drawer_layout);
        NavHostFragment navHostFragment = (NavHostFragment)
            getSupportFragmentManager().findFragmentById(R.id.main_content);
        navController = navHostFragment.getNavController();
        navigationView = findViewById(R.id.nav_view);

        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        // Show and Manage the Drawer and Back Icon
        NavigationUI.setupActionBarWithNavController(this, navController, drawerLayout);

        // Handle Navigation item clicks
        // This works with no further action on your part if the menu and destination id’s match.
        NavigationUI.setupWithNavController(navigationView, navController);

    }

    @Override
    public boolean onSupportNavigateUp() {
        // Allows NavigationUI to support proper up navigation or the drawer layout
        // drawer menu, depending on the situation.
        return NavigationUI.navigateUp(navController, drawerLayout);

    }
}

fun navigateToProductDetails(productId: String) {
    val intent = Intent(this, ProductDetailsActivity::class.java)
    intent.putExtra(KEY_PRODUCT_ID, productId)
    startActivity(intent)
}

private void navigateToProductDetails(String productId) {
    Intent intent = new Intent(this, ProductDetailsActivity.class);
    intent.putExtra(KEY_PRODUCT_ID, productId);
    startActivity(intent);

fun navigateToProductDetails(productId: String) {
    val directions = ProductListDirections.navigateToProductDetail(productId)
    findNavController().navigate(directions)
}

private void navigateToProductDetails(String productId) {
    ProductListDirections.NavigateToProductDetail directions =
            ProductListDirections.navigateToProductDetail(productId);
    Navigation.findNavController(getView()).navigate(directions);

class ProductDetailsActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.product_details_host)
        val navHostFragment = supportFragmentManager.findFragmentById(R.id.main_content) as NavHostFragment
        val navController = navHostFramgent.navController
        navController
                .setGraph(R.navigation.product_detail_graph, intent.extras)
    }

}

public class ProductDetailsActivity extends AppCompatActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.product_details_host);
        NavHostFragment navHostFragment = (NavHostFragment)
            getSupportFragmentManager().findFragmentById(R.id.main_content);
        NavController navController = navHostFragment.getNavController();
        navController
                .setGraph(R.navigation.product_detail_graph, getIntent().getExtras());
    }

}

class ProductDetailsFragment : Fragment() {

    val args by navArgs<ProductDetailsArgs>()

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        val productId = args.productId
        ...
    }
    ...

public class ProductDetailsFragment extends Fragment {

    ProductDetailsArgs args;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        args = ProductDetailsArgs.fromBundle(requireArguments());
    }

    @Override
    public void onViewCreated(@NonNull View view,
            @Nullable Bundle savedInstanceState) {
       int productId = args.getProductId();
       ...
    }
    ...

fun navigateToProductDetails(productId: String) {
    val directions = ProductListDirections.navigateToProductDetail(productId)
    findNavController().navigate(directions)
}

private void navigateToProductDetails(String productId) {
    ProductListDirections.NavigateToProductDetail directions =
            ProductListDirections.navigateToProductDetail(productId);
    Navigation.findNavController(getView()).navigate(directions);