Product files

loads details of product, categories and cost of it

android/app/src/main/java/com/example/petstoremobile/adapters/ProductAdapter.java

@@ -1,72 +1,57 @@
 package com.example.petstoremobile.adapters;
 
-
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
+import android.view.*;
 import android.widget.TextView;
 import androidx.annotation.NonNull;
 import androidx.recyclerview.widget.RecyclerView;
 import com.example.petstoremobile.R;
-import com.example.petstoremobile.models.Product;
+import com.example.petstoremobile.dtos.ProductDTO;
 import java.util.List;
 
 public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductViewHolder> {
 
-    private List<Product> productList;
-    private OnProductClickListener productClickListener;
+    private List<ProductDTO> productList;
+    private OnProductClickListener listener;
 
-    // Interface for product click on recycler view
     public interface OnProductClickListener {
         void onProductClick(int position);
     }
 
-    // Constructor
-    public ProductAdapter(List<Product> productList, OnProductClickListener productClickListener) {
+    public ProductAdapter(List<ProductDTO> productList, OnProductClickListener listener) {
         this.productList = productList;
-        this.productClickListener = productClickListener;
+        this.listener = listener;
     }
 
-    // Get the controls of each row in recycler view
     public static class ProductViewHolder extends RecyclerView.ViewHolder {
-        TextView tvProductName, tvProductDesc, tvCategory, tvProductPrice, tvStockQuantity;
+        TextView tvName, tvCategory, tvDesc, tvPrice;
 
         public ProductViewHolder(@NonNull View v) {
             super(v);
-            tvProductName = v.findViewById(R.id.tvProductName);
-            tvProductDesc = v.findViewById(R.id.tvProductDesc);
+            tvName     = v.findViewById(R.id.tvProductName);
             tvCategory = v.findViewById(R.id.tvProductCategory);
-            tvProductPrice = v.findViewById(R.id.tvProductPrice);
-            tvStockQuantity = v.findViewById(R.id.tvStockQuantity);
+            tvDesc     = v.findViewById(R.id.tvProductDesc);
+            tvPrice    = v.findViewById(R.id.tvProductPrice);
         }
     }
 
-    // Create a new row view
     @NonNull
     @Override
     public ProductViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
-        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_product, parent, false);
+        View v = LayoutInflater.from(parent.getContext())
+                .inflate(R.layout.item_product, parent, false);
         return new ProductViewHolder(v);
     }
 
-    // Populate the row with product data
     @Override
     public void onBindViewHolder(@NonNull ProductViewHolder holder, int position) {
-        Product product = productList.get(position);
-
-        holder.tvProductName.setText(product.getProductName());
-        holder.tvProductDesc.setText(product.getProductDesc());
-        holder.tvCategory.setText(product.getCategory());
-        holder.tvProductPrice.setText("$" + String.format("%.2f", product.getProductPrice()));
-        holder.tvStockQuantity.setText("Stock: " + product.getStockQuantity());
-
-        // When a row is clicked, open the detail view
-        holder.itemView.setOnClickListener(v -> productClickListener.onProductClick(position));
+        ProductDTO p = productList.get(position);
+        holder.tvName.setText(p.getProdName() != null ? p.getProdName() : "");
+        holder.tvCategory.setText("Category: " + (p.getCategoryName() != null ? p.getCategoryName() : ""));
+        holder.tvDesc.setText(p.getProdDesc() != null ? p.getProdDesc() : "");
+        holder.tvPrice.setText(p.getProdPrice() != null ? "$" + p.getProdPrice() : "");
+        holder.itemView.setOnClickListener(v -> listener.onProductClick(position));
     }
 
     @Override
-    public int getItemCount() {
-        return productList.size();
-    }
-}
-
+    public int getItemCount() { return productList.size(); }
+}

android/app/src/main/java/com/example/petstoremobile/api/ProductApi.java

@@ -0,0 +1,27 @@
+package com.example.petstoremobile.api;
+
+import com.example.petstoremobile.dtos.PageResponse;
+import com.example.petstoremobile.dtos.ProductDTO;
+import retrofit2.Call;
+import retrofit2.http.*;
+
+public interface ProductApi {
+
+    @GET("api/v1/products")
+    Call<PageResponse<ProductDTO>> getAllProducts(
+            @Query("q") String query,
+            @Query("page") int page,
+            @Query("size") int size);
+
+    @GET("api/v1/products/{id}")
+    Call<ProductDTO> getProductById(@Path("id") Long id);
+
+    @POST("api/v1/products")
+    Call<ProductDTO> createProduct(@Body ProductDTO product);
+
+    @PUT("api/v1/products/{id}")
+    Call<ProductDTO> updateProduct(@Path("id") Long id, @Body ProductDTO product);
+
+    @DELETE("api/v1/products/{id}")
+    Call<Void> deleteProduct(@Path("id") Long id);
+}

android/app/src/main/java/com/example/petstoremobile/dtos/ProductDTO.java

@@ -0,0 +1,81 @@
+package com.example.petstoremobile.dtos;
+
+import java.math.BigDecimal;
+
+public class ProductDTO {
+    private Long prodId;
+    private String prodName;
+    private Long categoryId;
+    private String categoryName;
+    private String prodDesc;
+    private BigDecimal prodPrice;
+    private String createdAt;
+    private String updatedAt;
+
+    public ProductDTO() {
+    }
+
+    // Constructor for create/update
+    public ProductDTO(String prodName, Long categoryId, String prodDesc, BigDecimal prodPrice) {
+        this.prodName = prodName;
+        this.categoryId = categoryId;
+        this.prodDesc = prodDesc;
+        this.prodPrice = prodPrice;
+    }
+
+    public Long getProdId() {
+        return prodId;
+    }
+
+    public void setProdId(Long prodId) {
+        this.prodId = prodId;
+    }
+
+    public String getProdName() {
+        return prodName;
+    }
+
+    public void setProdName(String prodName) {
+        this.prodName = prodName;
+    }
+
+    public Long getCategoryId() {
+        return categoryId;
+    }
+
+    public void setCategoryId(Long categoryId) {
+        this.categoryId = categoryId;
+    }
+
+    public String getCategoryName() {
+        return categoryName;
+    }
+
+    public void setCategoryName(String categoryName) {
+        this.categoryName = categoryName;
+    }
+
+    public String getProdDesc() {
+        return prodDesc;
+    }
+
+    public void setProdDesc(String prodDesc) {
+        this.prodDesc = prodDesc;
+    }
+
+    public BigDecimal getProdPrice() {
+        return prodPrice;
+    }
+
+    public void setProdPrice(BigDecimal prodPrice) {
+        this.prodPrice = prodPrice;
+    }
+
+    public String getCreatedAt() {
+        return createdAt;
+    }
+
+    public String getUpdatedAt() {
+        return updatedAt;
+    }
+}

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/ProductFragment.java

@@ -1,88 +1,87 @@
 package com.example.petstoremobile.fragments.listfragments;
 
-// Added search/filter bar to filter products by name or category.
-// Added pull-to-refresh using SwipeRefreshLayout.
-
 import android.os.Bundle;
+import android.text.*;
+import android.util.Log;
+import android.view.*;
+import android.widget.*;
 import androidx.fragment.app.Fragment;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
-import android.text.Editable;
-import android.text.TextWatcher;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.EditText;
-import android.widget.ImageButton;
-
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.ProductAdapter;
+import com.example.petstoremobile.api.RetrofitClient;
+import com.example.petstoremobile.dtos.PageResponse;
+import com.example.petstoremobile.dtos.ProductDTO;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.detailfragments.ProductDetailFragment;
-import com.example.petstoremobile.models.Product;
 import com.google.android.material.floatingactionbutton.FloatingActionButton;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.*;
+import retrofit2.*;
 
 public class ProductFragment extends Fragment implements ProductAdapter.OnProductClickListener {
 
-    private List<Product> productList = new ArrayList<>();
-    private List<Product> filteredList = new ArrayList<>();
+    private List<ProductDTO> productList = new ArrayList<>();
+    private List<ProductDTO> filteredList = new ArrayList<>();
     private ProductAdapter adapter;
-    private SwipeRefreshLayout swipeRefreshLayout;
+    private SwipeRefreshLayout swipeRefresh;
     private EditText etSearch;
-    private ImageButton hamburger;
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_product, container, false);
 
-        hamburger = view.findViewById(R.id.btnHamburger);
-
-        loadProductData(); // TODO: Replace with actual API call when backend is ready
         setupRecyclerView(view);
         setupSearch(view);
         setupSwipeRefresh(view);
+        loadProducts();
 
-        FloatingActionButton fabAddProduct = view.findViewById(R.id.fabAddProduct);
-        fabAddProduct.setOnClickListener(v -> openProductDetails(-1));
+        FloatingActionButton fab = view.findViewById(R.id.fabAddProduct);
+        fab.setOnClickListener(v -> openDetail(-1));
 
-        //Make the hamburger button open the drawer from listFragment
+        ImageButton hamburger = view.findViewById(R.id.btnHamburgerProduct);
         hamburger.setOnClickListener(v -> {
-            ListFragment listFragment = (ListFragment) getParentFragment();
-            //if list fragment is found then use its helper function to open the drawer
-            if (listFragment != null) {
-                listFragment.openDrawer();
-            }
+            ListFragment lf = (ListFragment) getParentFragment();
+            if (lf != null) lf.openDrawer();
         });
 
         return view;
     }
 
-    // Filters products by name, description, or category
+    private void setupRecyclerView(View view) {
+        RecyclerView rv = view.findViewById(R.id.recyclerViewProducts);
+        adapter = new ProductAdapter(filteredList, this);
+        rv.setLayoutManager(new LinearLayoutManager(getContext()));
+        rv.setAdapter(adapter);
+    }
+
     private void setupSearch(View view) {
         etSearch = view.findViewById(R.id.etSearchProduct);
         etSearch.addTextChangedListener(new TextWatcher() {
-            @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
-            @Override public void onTextChanged(CharSequence s, int start, int before, int count) {
-                filterProducts(s.toString());
+            public void beforeTextChanged(CharSequence s, int a, int b, int c) {}
+            public void afterTextChanged(Editable s) {}
+            public void onTextChanged(CharSequence s, int a, int b, int c) {
+                filter(s.toString());
             }
-            @Override public void afterTextChanged(Editable s) {}
         });
     }
 
-    private void filterProducts(String query) {
+    private void setupSwipeRefresh(View view) {
+        swipeRefresh = view.findViewById(R.id.swipeRefreshProduct);
+        swipeRefresh.setOnRefreshListener(this::loadProducts);
+    }
+
+    private void filter(String query) {
         filteredList.clear();
         if (query.isEmpty()) {
             filteredList.addAll(productList);
         } else {
             String lower = query.toLowerCase();
-            for (Product p : productList) {
-                if (p.getProductName().toLowerCase().contains(lower)
-                        || p.getCategory().toLowerCase().contains(lower)
-                        || p.getProductDesc().toLowerCase().contains(lower)) {
+            for (ProductDTO p : productList) {
+                if ((p.getProdName() != null && p.getProdName().toLowerCase().contains(lower))
+                        || (p.getCategoryName() != null && p.getCategoryName().toLowerCase().contains(lower))) {
                     filteredList.add(p);
                 }
             }
@@ -90,73 +89,45 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
         adapter.notifyDataSetChanged();
     }
 
-    private void setupSwipeRefresh(View view) {
-        swipeRefreshLayout = view.findViewById(R.id.swipeRefreshProduct);
-        swipeRefreshLayout.setOnRefreshListener(() -> {
-            loadProductData(); // TODO: Replace with actual API call
-            filterProducts(etSearch.getText().toString());
-            swipeRefreshLayout.setRefreshing(false);
-        });
+    private void loadProducts() {
+        if (swipeRefresh != null) swipeRefresh.setRefreshing(true);
+        RetrofitClient.getProductApi(requireContext()).getAllProducts(null, 0, 100)
+                .enqueue(new Callback<PageResponse<ProductDTO>>() {
+                    public void onResponse(Call<PageResponse<ProductDTO>> c,
+                                           Response<PageResponse<ProductDTO>> r) {
+                        if (swipeRefresh != null) swipeRefresh.setRefreshing(false);
+                        if (r.isSuccessful() && r.body() != null) {
+                            productList.clear();
+                            productList.addAll(r.body().getContent());
+                            filter(etSearch != null ? etSearch.getText().toString() : "");
+                        } else {
+                            Toast.makeText(getContext(), "Failed to load products",
+                                    Toast.LENGTH_SHORT).show();
+                        }
+                    }
+                    public void onFailure(Call<PageResponse<ProductDTO>> c, Throwable t) {
+                        if (swipeRefresh != null) swipeRefresh.setRefreshing(false);
+                        Log.e("ProductFragment", t.getMessage());
+                    }
+                });
     }
 
-    private void openProductDetails(int position) {
-        ProductDetailFragment detailFragment = new ProductDetailFragment();
+    private void openDetail(int position) {
+        ProductDetailFragment detail = new ProductDetailFragment();
         Bundle args = new Bundle();
-        args.putInt("position", position);
-
         if (position != -1) {
-            Product product = filteredList.get(position);
-            int realPosition = productList.indexOf(product);
-            args.putInt("position", realPosition);
-            args.putInt("productId", product.getProductId());
-            args.putString("productName", product.getProductName());
-            args.putString("productDesc", product.getProductDesc());
-            args.putString("category", product.getCategory());
-            args.putDouble("productPrice", product.getProductPrice());
-            args.putInt("stockQuantity", product.getStockQuantity());
+            ProductDTO p = filteredList.get(position);
+            args.putLong("prodId", p.getProdId());
+            args.putString("prodName", p.getProdName());
+            args.putString("prodDesc", p.getProdDesc() != null ? p.getProdDesc() : "");
+            args.putString("prodPrice", p.getProdPrice() != null ? p.getProdPrice().toString() : "");
+            args.putLong("categoryId", p.getCategoryId() != null ? p.getCategoryId() : -1);
         }
-
-        detailFragment.setArguments(args);
-        detailFragment.setProductFragment(this);
-
-        ListFragment listFragment = (ListFragment) getParentFragment();
-        if (listFragment != null) listFragment.loadFragment(detailFragment);
-    }
-
-    public void onProductSaved(int position, Product product) {
-        if (position == -1) {
-            productList.add(product);
-        } else {
-            productList.set(position, product);
-        }
-        filterProducts(etSearch.getText().toString());
-    }
-
-    public void onProductDeleted(int position) {
-        productList.remove(position);
-        filterProducts(etSearch.getText().toString());
+        detail.setArguments(args);
+        ListFragment lf = (ListFragment) getParentFragment();
+        if (lf != null) lf.loadFragment(detail);
     }
 
     @Override
-    public void onProductClick(int position) {
-        openProductDetails(position);
-    }
-
-    private void loadProductData() {
-        productList.clear();
-        productList.add(new Product(1, "Premium Dog Food", "High protein dry food for adult dogs", "Food", 45.99, 25));
-        productList.add(new Product(2, "Cat Toy Bundle", "Set of 5 interactive toys", "Toys", 19.99, 40));
-        productList.add(new Product(3, "Pet Shampoo", "Gentle formula for all breeds", "Grooming", 12.99, 60));
-        productList.add(new Product(4, "Dog Bed - Large", "Memory foam orthopedic bed", "Bedding", 89.99, 10));
-        productList.add(new Product(5, "Aquarium Starter Kit", "20-gallon tank with filter and light", "Aquatic", 129.99, 5));
-        filteredList.clear();
-        filteredList.addAll(productList);
-    }
-
-    private void setupRecyclerView(View view) {
-        RecyclerView recyclerView = view.findViewById(R.id.recyclerViewProducts);
-        adapter = new ProductAdapter(filteredList, this);
-        recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
-        recyclerView.setAdapter(adapter);
-    }
-}
+    public void onProductClick(int position) { openDetail(position); }
+}

android/app/src/main/java/com/example/petstoremobile/fragments/listfragments/detailfragments/ProductDetailFragment.java

@@ -1,139 +1,190 @@
 package com.example.petstoremobile.fragments.listfragments.detailfragments;
 
-// Uses InputValidator for detailed field validation and ActivityLogger to log all changes.
-
 import android.os.Bundle;
+import android.util.Log;
+import android.view.*;
+import android.widget.*;
+import androidx.annotation.NonNull;
+import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.Fragment;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.Button;
-import android.widget.EditText;
-import android.widget.TextView;
-import android.widget.Toast;
 import com.example.petstoremobile.R;
+import com.example.petstoremobile.api.*;
+import com.example.petstoremobile.dtos.*;
 import com.example.petstoremobile.fragments.ListFragment;
-import com.example.petstoremobile.fragments.listfragments.ProductFragment;
-import com.example.petstoremobile.models.Product;
-import com.example.petstoremobile.utils.ActivityLogger;
-import com.example.petstoremobile.utils.InputValidator;
+import java.math.BigDecimal;
+import java.util.*;
+import retrofit2.*;
 
 public class ProductDetailFragment extends Fragment {
 
     private TextView tvMode, tvProductId;
-    private EditText etProductName, etProductDesc, etCategory, etProductPrice, etStockQuantity;
-    private Button btnSaveProduct, btnDeleteProduct, btnBack;
-    private int productId;
-    private int position;
-    private boolean isEditing = false;
-    private ProductFragment productFragment;
+    private EditText etProductName, etProductDesc, etProductPrice;
+    private Spinner spinnerCategory;
+    private Button btnSave, btnDelete, btnBack;
 
-    // Set the product fragment as parent so we refer back when save or delete is done
-    public void setProductFragment(ProductFragment fragment) {
-        this.productFragment = fragment;
-    }
+    private long prodId = -1;
+    private boolean isEditing = false;
+    private long preselectedCategoryId = -1;
+
+    private List<CategoryDTO> categoryList = new ArrayList<>();
 
     @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_product_detail, container, false);
-
         initViews(view);
+        loadCategories();
         handleArguments();
 
-        btnBack.setOnClickListener(v -> {
-            ListFragment listFragment = (ListFragment) getParentFragment();
-            if (listFragment != null) listFragment.getChildFragmentManager().popBackStack();
-        });
-        btnSaveProduct.setOnClickListener(v -> saveProduct());
-        btnDeleteProduct.setOnClickListener(v -> deleteProduct());
-
+        btnBack.setOnClickListener(v -> navigateBack());
+        btnSave.setOnClickListener(v -> saveProduct());
+        btnDelete.setOnClickListener(v -> confirmDelete());
         return view;
     }
 
-    // Validates all fields using InputValidator, then saves the product
-    private void saveProduct() {
-        if (!InputValidator.isNotEmpty(etProductName, "Product Name")) return;
-        if (!InputValidator.isNotEmpty(etProductDesc, "Description")) return;
-        if (!InputValidator.isNotEmpty(etCategory, "Category")) return;
-        if (!InputValidator.isPositiveDecimal(etProductPrice, "Price")) return;
-        if (!InputValidator.isPositiveInteger(etStockQuantity, "Stock Quantity")) return;
-
-        String productName = etProductName.getText().toString().trim();
-        String productDesc = etProductDesc.getText().toString().trim();
-        String category = etCategory.getText().toString().trim();
-        double productPrice = Double.parseDouble(etProductPrice.getText().toString().trim());
-        int stockQuantity = Integer.parseInt(etStockQuantity.getText().toString().trim());
-
-        try {
-            if (isEditing) {
-                // TODO: Replace with actual API PUT call when backend is ready
-                Product updated = new Product(productId, productName, productDesc, category, productPrice, stockQuantity);
-                if (productFragment != null) productFragment.onProductSaved(position, updated);
-                ActivityLogger.logChange(requireContext(), "Product", "UPDATED", productId);
-                Toast.makeText(getContext(), "Product updated.", Toast.LENGTH_SHORT).show();
-            } else {
-                // TODO: Replace with actual API POST call when backend is ready
-                Product newProduct = new Product(0, productName, productDesc, category, productPrice, stockQuantity);
-                if (productFragment != null) productFragment.onProductSaved(-1, newProduct);
-                ActivityLogger.log(requireContext(), "Added new Product: " + productName);
-                Toast.makeText(getContext(), "Product added.", Toast.LENGTH_SHORT).show();
-            }
-            ListFragment listFragment = (ListFragment) getParentFragment();
-            if (listFragment != null) listFragment.getChildFragmentManager().popBackStack();
-        } catch (Exception e) {
-            ActivityLogger.logException(requireContext(), "ProductDetailFragment.saveProduct", e);
-            Toast.makeText(getContext(), "Error saving product.", Toast.LENGTH_SHORT).show();
-        }
+    private void initViews(View v) {
+        tvMode          = v.findViewById(R.id.tvProductMode);
+        tvProductId     = v.findViewById(R.id.tvProductId);
+        etProductName   = v.findViewById(R.id.etProductName);
+        etProductDesc   = v.findViewById(R.id.etProductDesc);
+        etProductPrice  = v.findViewById(R.id.etProductPrice);
+        spinnerCategory = v.findViewById(R.id.spinnerProductCategory);
+        btnSave         = v.findViewById(R.id.btnSaveProduct);
+        btnDelete       = v.findViewById(R.id.btnDeleteProduct);
+        btnBack         = v.findViewById(R.id.btnProductBack);
     }
 
-    // Deletes the product and logs the action
-    private void deleteProduct() {
-        try {
-            // TODO: Replace with actual API DELETE call when backend is ready
-            if (productFragment != null) productFragment.onProductDeleted(position);
-            ActivityLogger.logChange(requireContext(), "Product", "DELETED", productId);
-            Toast.makeText(getContext(), "Product deleted.", Toast.LENGTH_SHORT).show();
-            ListFragment listFragment = (ListFragment) getParentFragment();
-            if (listFragment != null) listFragment.getChildFragmentManager().popBackStack();
-        } catch (Exception e) {
-            ActivityLogger.logException(requireContext(), "ProductDetailFragment.deleteProduct", e);
-            Toast.makeText(getContext(), "Error deleting product.", Toast.LENGTH_SHORT).show();
+    private void loadCategories() {
+        RetrofitClient.getCategoryApi(requireContext()).getAllCategories(0, 100)
+                .enqueue(new Callback<PageResponse<CategoryDTO>>() {
+                    public void onResponse(Call<PageResponse<CategoryDTO>> c,
+                                           Response<PageResponse<CategoryDTO>> r) {
+                        if (r.isSuccessful() && r.body() != null) {
+                            categoryList = r.body().getContent();
+                            populateCategorySpinner();
+                        }
+                    }
+                    public void onFailure(Call<PageResponse<CategoryDTO>> c, Throwable t) {
+                        Log.e("ProductDetail", "Category load failed: " + t.getMessage());
+                    }
+                });
+    }
+
+    private void populateCategorySpinner() {
+        List<String> names = new ArrayList<>();
+        names.add("-- Select Category --");
+        for (CategoryDTO c : categoryList) names.add(c.getCategoryName());
+        spinnerCategory.setAdapter(new ArrayAdapter<>(requireContext(),
+                android.R.layout.simple_spinner_item, names));
+        if (preselectedCategoryId != -1) {
+            for (int i = 0; i < categoryList.size(); i++) {
+                if (categoryList.get(i).getCategoryId().equals(preselectedCategoryId)) {
+                    spinnerCategory.setSelection(i + 1); break;
+                }
+            }
         }
     }
 
     private void handleArguments() {
-        if (getArguments() != null && getArguments().containsKey("productId")) {
+        Bundle a = getArguments();
+        if (a != null && a.containsKey("prodId")) {
             isEditing = true;
-            productId = getArguments().getInt("productId");
-            position = getArguments().getInt("position");
+            prodId = a.getLong("prodId");
+            preselectedCategoryId = a.getLong("categoryId", -1);
+
             tvMode.setText("Edit Product");
-            tvProductId.setText("ID: " + productId);
-            etProductName.setText(getArguments().getString("productName"));
-            etProductDesc.setText(getArguments().getString("productDesc"));
-            etCategory.setText(getArguments().getString("category"));
-            etProductPrice.setText(String.valueOf(getArguments().getDouble("productPrice")));
-            etStockQuantity.setText(String.valueOf(getArguments().getInt("stockQuantity")));
-            btnDeleteProduct.setVisibility(View.VISIBLE);
+            tvProductId.setText("ID: " + prodId);
+            tvProductId.setVisibility(View.VISIBLE);
+            etProductName.setText(a.getString("prodName"));
+            etProductDesc.setText(a.getString("prodDesc"));
+            etProductPrice.setText(a.getString("prodPrice"));
+            btnDelete.setVisibility(View.VISIBLE);
         } else {
-            isEditing = false;
             tvMode.setText("Add Product");
+            btnDelete.setVisibility(View.GONE);
             tvProductId.setVisibility(View.GONE);
-            btnDeleteProduct.setVisibility(View.GONE);
-            btnSaveProduct.setText("Add");
         }
     }
 
-    private void initViews(View view) {
-        tvMode = view.findViewById(R.id.tvProductMode);
-        tvProductId = view.findViewById(R.id.tvProductId);
-        etProductName = view.findViewById(R.id.etProductName);
-        etProductDesc = view.findViewById(R.id.etProductDesc);
-        etCategory = view.findViewById(R.id.etProductCategory);
-        etProductPrice = view.findViewById(R.id.etProductPrice);
-        etStockQuantity = view.findViewById(R.id.etStockQuantity);
-        btnSaveProduct = view.findViewById(R.id.btnSaveProduct);
-        btnDeleteProduct = view.findViewById(R.id.btnDeleteProduct);
-        btnBack = view.findViewById(R.id.btnProductBack);
+    private void saveProduct() {
+        String name = etProductName.getText().toString().trim();
+        String desc = etProductDesc.getText().toString().trim();
+        String priceStr = etProductPrice.getText().toString().trim();
+
+        if (name.isEmpty()) {
+            etProductName.setError("Enter product name"); return;
+        }
+        if (spinnerCategory.getSelectedItemPosition() == 0) {
+            Toast.makeText(getContext(), "Select a category", Toast.LENGTH_SHORT).show(); return;
+        }
+        if (priceStr.isEmpty()) {
+            etProductPrice.setError("Enter price"); return;
+        }
+
+        CategoryDTO category = categoryList.get(spinnerCategory.getSelectedItemPosition() - 1);
+        BigDecimal price;
+        try {
+            price = new BigDecimal(priceStr);
+        } catch (Exception e) {
+            etProductPrice.setError("Invalid price"); return;
+        }
+
+        ProductDTO dto = new ProductDTO(name, category.getCategoryId(), desc, price);
+
+        Log.d("PRODUCT_SAVE", "name=" + name + " categoryId=" + category.getCategoryId()
+                + " price=" + price);
+
+        ProductApi api = RetrofitClient.getProductApi(requireContext());
+        if (isEditing) {
+            api.updateProduct(prodId, dto).enqueue(simpleCallback("Updated"));
+        } else {
+            api.createProduct(dto).enqueue(simpleCallback("Saved"));
+        }
     }
-}
+
+    private Callback<ProductDTO> simpleCallback(String msg) {
+        return new Callback<>() {
+            public void onResponse(Call<ProductDTO> c, Response<ProductDTO> r) {
+                if (r.isSuccessful()) {
+                    Toast.makeText(getContext(), msg, Toast.LENGTH_SHORT).show();
+                    navigateBack();
+                } else {
+                    try {
+                        String err = r.errorBody().string();
+                        Log.e("PRODUCT_SAVE", "Error: " + err);
+                        Toast.makeText(getContext(), "Error " + r.code(), Toast.LENGTH_SHORT).show();
+                    } catch (Exception e) {
+                        Log.e("PRODUCT_SAVE", "Failed to read error");
+                    }
+                }
+            }
+            public void onFailure(Call<ProductDTO> c, Throwable t) {
+                Log.e("PRODUCT_SAVE", "Failure: " + t.getMessage());
+                Toast.makeText(getContext(), "Network error", Toast.LENGTH_SHORT).show();
+            }
+        };
+    }
+
+    private void confirmDelete() {
+        new AlertDialog.Builder(requireContext())
+                .setTitle("Delete Product?")
+                .setPositiveButton("Yes", (d, w) ->
+                        RetrofitClient.getProductApi(requireContext())
+                                .deleteProduct(prodId)
+                                .enqueue(new Callback<Void>() {
+                                    public void onResponse(Call<Void> c, Response<Void> r) {
+                                        navigateBack();
+                                    }
+                                    public void onFailure(Call<Void> c, Throwable t) {
+                                        Toast.makeText(getContext(), "Delete failed",
+                                                Toast.LENGTH_SHORT).show();
+                                    }
+                                }))
+                .setNegativeButton("No", null).show();
+    }
+
+    private void navigateBack() {
+        ListFragment lf = (ListFragment) getParentFragment();
+        if (lf != null) lf.getChildFragmentManager().popBackStack();
+    }
+}

android/app/src/main/res/layout/fragment_product.xml

@@ -12,7 +12,6 @@
         android:orientation="vertical">
 
         <LinearLayout
-            android:id="@+id/header"
             android:layout_width="match_parent"
             android:layout_height="56dp"
             android:background="@color/primary_dark"
@@ -21,7 +20,7 @@
             android:paddingEnd="16dp">
 
             <ImageButton
-                android:id="@+id/btnHamburger"
+                android:id="@+id/btnHamburgerProduct"
                 android:layout_width="48dp"
                 android:layout_height="48dp"
                 android:src="@drawable/baseline_menu_36"
@@ -43,7 +42,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_margin="8dp"
-            android:hint="Search by product name or category..."
+            android:hint="Search by name or category..."
             android:inputType="text"
             android:drawableStart="@android:drawable/ic_menu_search"
             android:drawablePadding="8dp"

android/app/src/main/res/layout/fragment_product_detail.xml

@@ -28,10 +28,9 @@
             android:id="@+id/btnDeleteProduct"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_marginStart="8dp"
             android:backgroundTint="@color/accent_coral"
             android:text="Delete"
-            android:textColor="@color/white" />
+            android:textColor="@color/white"/>
 
     </LinearLayout>
 
@@ -65,6 +64,7 @@
                     android:layout_gravity="end"
                     android:layout_marginBottom="8dp"/>
 
+                <!-- Product Name -->
                 <TextView
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
@@ -81,6 +81,22 @@
                     android:inputType="text"
                     android:layout_marginBottom="16dp"/>
 
+                <!-- Category -->
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Category"
+                    android:textColor="@color/text_dark"
+                    android:textSize="12sp"
+                    android:layout_marginBottom="4dp"/>
+
+                <Spinner
+                    android:id="@+id/spinnerProductCategory"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginBottom="16dp"/>
+
+                <!-- Description -->
                 <TextView
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
@@ -93,27 +109,12 @@
                     android:id="@+id/etProductDesc"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
-                    android:layout_marginBottom="16dp"
-                    android:hint="Enter product description"
+                    android:hint="Enter description"
                     android:inputType="textMultiLine"
-                    android:minLines="1" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:text="Category"
-                    android:textColor="@color/text_dark"
-                    android:textSize="12sp"
-                    android:layout_marginBottom="4dp"/>
-
-                <EditText
-                    android:id="@+id/etProductCategory"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:hint="e.g. Food, Toys, Grooming"
-                    android:inputType="text"
+                    android:minLines="2"
                     android:layout_marginBottom="16dp"/>
 
+                <!-- Price -->
                 <TextView
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
@@ -126,24 +127,9 @@
                     android:id="@+id/etProductPrice"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
-                    android:hint="Enter price"
+                    android:hint="0.00"
                     android:inputType="numberDecimal"
-                    android:layout_marginBottom="16dp"/>
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:text="Stock Quantity"
-                    android:textColor="@color/text_dark"
-                    android:textSize="12sp"
-                    android:layout_marginBottom="4dp"/>
-
-                <EditText
-                    android:id="@+id/etStockQuantity"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:hint="Enter stock quantity"
-                    android:inputType="number"/>
+                    android:layout_marginBottom="8dp"/>
 
             </LinearLayout>