integrated hilt so we dont have to manually pass context and inject retrofit in andriod

android/app/build.gradle.kts

@@ -2,6 +2,7 @@ import java.util.Properties
 
 plugins {
     alias(libs.plugins.android.application)
+    alias(libs.plugins.hilt)
 }
 
 val localProperties = Properties().apply {
@@ -60,6 +61,9 @@ dependencies {
     implementation(libs.activity)
     implementation(libs.constraintlayout)
 
+    implementation(libs.hilt.android)
+    annotationProcessor(libs.hilt.compiler)
+
     implementation("com.squareup.retrofit2:retrofit:2.9.0")
     implementation("com.squareup.retrofit2:converter-gson:2.9.0")
     implementation("com.squareup.okhttp3:logging-interceptor:4.12.0")

android/app/src/main/java/com/example/petstoremobile/PetStoreApplication.java

@@ -1,8 +1,9 @@
 package com.example.petstoremobile;
 
 import android.app.Application;
-import com.example.petstoremobile.api.auth.TokenManager;
+import dagger.hilt.android.HiltAndroidApp;
 
+@HiltAndroidApp
 public class PetStoreApplication extends Application {
     @Override
     public void onCreate() {

android/app/src/main/java/com/example/petstoremobile/activities/HomeActivity.java

@@ -10,7 +10,6 @@ import android.util.Log;
 import androidx.activity.EdgeToEdge;
 import androidx.activity.result.ActivityResultLauncher;
 import androidx.activity.result.contract.ActivityResultContracts;
-import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.core.content.ContextCompat;
 import androidx.core.graphics.Insets;
@@ -25,6 +24,9 @@ import com.example.petstoremobile.fragments.ProfileFragment;
 import com.example.petstoremobile.services.ChatNotificationService;
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 
+import dagger.hilt.android.AndroidEntryPoint;
+
+@AndroidEntryPoint
 public class HomeActivity extends AppCompatActivity {
     private BottomNavigationView bottomNav;
 
@@ -125,4 +127,4 @@ public class HomeActivity extends AppCompatActivity {
                 .replace(R.id.fragment_container, fragment)
                 .commit();
     }
-}
+}

android/app/src/main/java/com/example/petstoremobile/activities/MainActivity.java

@@ -18,15 +18,19 @@ import androidx.core.view.WindowInsetsCompat;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.api.auth.AuthApi;
 import com.example.petstoremobile.api.auth.TokenManager;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.AuthDTO;
 import com.example.petstoremobile.dtos.UserDTO;
 
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
 //The login screen activity
+@AndroidEntryPoint
 public class MainActivity extends AppCompatActivity {
 
     private EditText etUser;
@@ -34,6 +38,10 @@ public class MainActivity extends AppCompatActivity {
     private Button btnLogin;
     private TextView tvLoginStatus;
 
+    @Inject AuthApi authApi;
+    @Inject TokenManager tokenManager;
+    @Inject @Named("baseUrl") String baseUrl;
+
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -41,7 +49,6 @@ public class MainActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
 
         // Check if user is already logged in
-        TokenManager tokenManager = TokenManager.getInstance(this);
         if (tokenManager.isLoggedIn()) {
             if ("CUSTOMER".equalsIgnoreCase(tokenManager.getRole())) {
                 // If a customer somehow remained logged in, clear them out
@@ -92,8 +99,6 @@ public class MainActivity extends AppCompatActivity {
                 return;
             }
 
-            AuthApi authApi = RetrofitClient.getAuthApi(this);
-
             //Call login from api and get response
             authApi.login(new AuthDTO.LoginRequest(username,password)).enqueue(new Callback<AuthDTO.LoginResponse>() {
                 @Override
@@ -109,21 +114,20 @@ public class MainActivity extends AppCompatActivity {
                         }
 
                         //save login data in shared preferences
-                        TokenManager.getInstance(MainActivity.this).saveLoginData(
+                        tokenManager.saveLoginData(
                                 response.body().getToken(),
                                 response.body().getUsername(),
                                 role
                         );
 
                         //fetch user id from api then login to home activity
-                        RetrofitClient.getAuthApi(MainActivity.this).getMe()
+                        authApi.getMe()
                                 .enqueue(new Callback<UserDTO>() {
                                     @Override
                                     public void onResponse(Call<UserDTO> call,
                                                            Response<UserDTO> response) {
                                         if (response.isSuccessful() && response.body() != null) {
-                                            TokenManager.getInstance(MainActivity.this)
+                                            tokenManager.saveUserId(response.body().getId());
-                                                    .saveUserId(response.body().getId());
                                         }
 
                                         Toast.makeText(MainActivity.this, "Login successful", Toast.LENGTH_SHORT).show();
@@ -169,7 +173,7 @@ public class MainActivity extends AppCompatActivity {
                     if (t instanceof java.net.ConnectException ||
                         t instanceof java.net.SocketTimeoutException ||
                         t instanceof java.net.UnknownHostException) {
-                        errorMessage = "Cannot connect to server at " + RetrofitClient.BASE_URL +
+                        errorMessage = "Cannot connect to server at " + baseUrl +
                                 ". Please check if the backend is running.";
                     } else if (t instanceof java.io.IOException) {
                         errorMessage = "Network error. Please check your connection.";
@@ -183,4 +187,4 @@ public class MainActivity extends AppCompatActivity {
             });
         });
     }
-}
+}

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

@@ -13,7 +13,6 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.api.PetApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.PetDTO;
 import java.util.List;
 
@@ -21,6 +20,7 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> {
 
     private List<PetDTO> petList;
     private OnPetClickListener petClickListener;
+    private String baseUrl;
 
     // Interface for pet click on recycler view
     public interface OnPetClickListener {
@@ -33,6 +33,10 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> {
         this.petClickListener = petClickListener;
     }
 
+    public void setBaseUrl(String baseUrl) {
+        this.baseUrl = baseUrl;
+    }
+
     // Get the controls of each row in recycler view
     public static class PetViewHolder extends RecyclerView.ViewHolder {
         TextView tvPetName, tvPetSpeciesBreed, tvPetAge, tvPetPrice, tvPetStatus;
@@ -83,15 +87,19 @@ public class PetAdapter extends RecyclerView.Adapter<PetAdapter.PetViewHolder> {
         }
 
         // Load pet image using Glide with circle crop
-        String imageUrl = RetrofitClient.BASE_URL + String.format(PetApi.PET_IMAGE_PATH, pet.getPetId());
+        if (baseUrl != null) {
-        Glide.with(holder.itemView.getContext())
+            String imageUrl = baseUrl + String.format(PetApi.PET_IMAGE_PATH, pet.getPetId());
-                .load(imageUrl)
+            Glide.with(holder.itemView.getContext())
-                .circleCrop()
+                    .load(imageUrl)
-                .diskCacheStrategy(DiskCacheStrategy.NONE)
+                    .circleCrop()
-                .skipMemoryCache(true)
+                    .diskCacheStrategy(DiskCacheStrategy.NONE)
-                .placeholder(R.drawable.placeholder)
+                    .skipMemoryCache(true)
-                .error(R.drawable.placeholder)
+                    .placeholder(R.drawable.placeholder)
-                .into(holder.ivPetProfile);
+                    .error(R.drawable.placeholder)
+                    .into(holder.ivPetProfile);
+        } else {
+            holder.ivPetProfile.setImageResource(R.drawable.placeholder);
+        }
 
         //when a row is clicked, open the detail view
         holder.itemView.setOnClickListener(v -> petClickListener.onPetClick(position));

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

@@ -10,7 +10,6 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.api.ProductApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.ProductDTO;
 import java.util.List;
 
@@ -18,6 +17,7 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
 
     private List<ProductDTO> productList;
     private OnProductClickListener listener;
+    private String baseUrl;
 
     public interface OnProductClickListener {
         void onProductClick(int position);
@@ -28,6 +28,10 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
         this.listener = listener;
     }
 
+    public void setBaseUrl(String baseUrl) {
+        this.baseUrl = baseUrl;
+    }
+
     public static class ProductViewHolder extends RecyclerView.ViewHolder {
         TextView tvName, tvCategory, tvDesc, tvPrice;
         ImageView ivProductImage;
@@ -59,15 +63,19 @@ public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductV
         holder.tvPrice.setText(p.getProdPrice() != null ? "$" + p.getProdPrice() : "");
 
         // Load product image using Glide
-        String imageUrl = RetrofitClient.BASE_URL + String.format(ProductApi.PRODUCT_IMAGE_PATH, p.getProdId());
+        if (baseUrl != null) {
-        Glide.with(holder.itemView.getContext())
+            String imageUrl = baseUrl + String.format(ProductApi.PRODUCT_IMAGE_PATH, p.getProdId());
-                .load(imageUrl)
+            Glide.with(holder.itemView.getContext())
-                .circleCrop()
+                    .load(imageUrl)
-                .diskCacheStrategy(DiskCacheStrategy.NONE)
+                    .circleCrop()
-                .skipMemoryCache(true)
+                    .diskCacheStrategy(DiskCacheStrategy.NONE)
-                .placeholder(R.drawable.placeholder)
+                    .skipMemoryCache(true)
-                .error(R.drawable.placeholder)
+                    .placeholder(R.drawable.placeholder)
-                .into(holder.ivProductImage);
+                    .error(R.drawable.placeholder)
+                    .into(holder.ivProductImage);
+        } else {
+            holder.ivProductImage.setImageResource(R.drawable.placeholder);
+        }
 
         holder.itemView.setOnClickListener(v -> listener.onProductClick(position));
     }

android/app/src/main/java/com/example/petstoremobile/api/auth/AuthInterceptor.java

@@ -1,7 +1,5 @@
 package com.example.petstoremobile.api.auth;
 
-import android.content.Context;
-
 import androidx.annotation.NonNull;
 
 import java.io.IOException;
@@ -15,8 +13,8 @@ public class AuthInterceptor implements Interceptor {
 
     private final TokenManager tokenManager;
 
-    public AuthInterceptor(Context context) {
+    public AuthInterceptor(TokenManager tokenManager) {
-        this.tokenManager = TokenManager.getInstance(context);
+        this.tokenManager = tokenManager;
     }
 
     @NonNull

android/app/src/main/java/com/example/petstoremobile/api/auth/TokenManager.java

@@ -3,7 +3,12 @@ package com.example.petstoremobile.api.auth;
 import android.content.Context;
 import android.content.SharedPreferences;
 
-//Store login token in shared preferences
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import dagger.hilt.android.qualifiers.ApplicationContext;
+
+@Singleton
 public class TokenManager {
     private static final String TOKEN_KEY = "token";
     private static final String USERNAME_KEY = "username";
@@ -11,20 +16,13 @@ public class TokenManager {
     private static final String PREFS_NAME = "auth_prefs";
     private static final String USER_ID_KEY = "user_id";
 
-    private static TokenManager instance;
     private SharedPreferences prefs;
 
-    private TokenManager(Context context) {
+    @Inject
+    public TokenManager(@ApplicationContext Context context) {
         prefs = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
     }
 
-    public static TokenManager getInstance(Context context) {
-        if (instance == null) {
-            instance = new TokenManager(context);
-        }
-        return instance;
-    }
-
     //save login data after login
     public void saveLoginData(String token, String username, String role) {
         prefs.edit()
@@ -65,6 +63,4 @@ public class TokenManager {
     public void clearLoginData() {
         prefs.edit().clear().apply();
     }
-
+}
-
-}

android/app/src/main/java/com/example/petstoremobile/di/NetworkModule.java

@@ -0,0 +1,176 @@
+package com.example.petstoremobile.di;
+
+import android.content.Context;
+import android.os.Build;
+
+import com.example.petstoremobile.BuildConfig;
+import com.example.petstoremobile.api.*;
+import com.example.petstoremobile.api.auth.AuthApi;
+import com.example.petstoremobile.api.auth.AuthInterceptor;
+import com.example.petstoremobile.api.auth.TokenManager;
+
+import java.util.concurrent.TimeUnit;
+
+import javax.inject.Named;
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+import dagger.hilt.InstallIn;
+import dagger.hilt.android.qualifiers.ApplicationContext;
+import dagger.hilt.components.SingletonComponent;
+import okhttp3.OkHttpClient;
+import okhttp3.logging.HttpLoggingInterceptor;
+import retrofit2.Retrofit;
+import retrofit2.converter.gson.GsonConverterFactory;
+
+//Module to provide dependencies injection for the api
+@Module
+@InstallIn(SingletonComponent.class)
+public class NetworkModule {
+
+    @Provides
+    @Singleton
+    @Named("baseUrl")
+    public static String provideBaseUrl() {
+        return isEmulator() ? BuildConfig.EMULATOR_BACKEND_URL : BuildConfig.DEVICE_BACKEND_URL;
+    }
+
+    // Check if the device is an emulator
+    private static boolean isEmulator() {
+        return Build.FINGERPRINT.startsWith("generic")
+                || Build.FINGERPRINT.startsWith("unknown")
+                || Build.MODEL.contains("google_sdk")
+                || Build.MODEL.contains("Emulator")
+                || Build.MODEL.contains("Android SDK built for x86")
+                || Build.MANUFACTURER.contains("Genymotion")
+                || Build.HARDWARE.contains("goldfish")
+                || Build.HARDWARE.contains("ranchu")
+                || Build.PRODUCT.contains("sdk")
+                || Build.PRODUCT.contains("sdk_gphone")
+                || (Build.BRAND.startsWith("generic") && Build.DEVICE.startsWith("generic"));
+    }
+
+    @Provides
+    @Singleton
+    public static OkHttpClient provideOkHttpClient(TokenManager tokenManager) {
+        HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
+        interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
+
+        return new OkHttpClient.Builder()
+                .addInterceptor(interceptor)
+                .addInterceptor(new AuthInterceptor(tokenManager))
+                .connectTimeout(30, TimeUnit.SECONDS)
+                .readTimeout(30, TimeUnit.SECONDS)
+                .writeTimeout(30, TimeUnit.SECONDS)
+                .build();
+    }
+
+    //build the retrofit instance
+    @Provides
+    @Singleton
+    public static Retrofit provideRetrofit(@Named("baseUrl") String baseUrl, OkHttpClient client) {
+        return new Retrofit.Builder()
+                .baseUrl(baseUrl)
+                .addConverterFactory(GsonConverterFactory.create())
+                .client(client)
+                .build();
+    }
+
+    //associate the api with the retrofit instance
+    @Provides
+    @Singleton
+    public static PetApi providePetApi(Retrofit retrofit) {
+        return retrofit.create(PetApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static ServiceApi provideServiceApi(Retrofit retrofit) {
+        return retrofit.create(ServiceApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static SupplierApi provideSupplierApi(Retrofit retrofit) {
+        return retrofit.create(SupplierApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static AdoptionApi provideAdoptionApi(Retrofit retrofit) {
+        return retrofit.create(AdoptionApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static AppointmentApi provideAppointmentApi(Retrofit retrofit) {
+        return retrofit.create(AppointmentApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static ProductApi provideProductApi(Retrofit retrofit) {
+        return retrofit.create(ProductApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static SaleApi provideSaleApi(Retrofit retrofit) {
+        return retrofit.create(SaleApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static PurchaseOrderApi providePurchaseOrderApi(Retrofit retrofit) {
+        return retrofit.create(PurchaseOrderApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static ProductSupplierApi provideProductSupplierApi(Retrofit retrofit) {
+        return retrofit.create(ProductSupplierApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static InventoryApi provideInventoryApi(Retrofit retrofit) {
+        return retrofit.create(InventoryApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static AuthApi provideAuthApi(Retrofit retrofit) {
+        return retrofit.create(AuthApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static ChatApi provideChatApi(Retrofit retrofit) {
+        return retrofit.create(ChatApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static CustomerApi provideCustomerApi(Retrofit retrofit) {
+        return retrofit.create(CustomerApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static MessageApi provideMessageApi(Retrofit retrofit) {
+        return retrofit.create(MessageApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static StoreApi provideStoreApi(Retrofit retrofit) {
+        return retrofit.create(StoreApi.class);
+    }
+
+    @Provides
+    @Singleton
+    public static CategoryApi provideCategoryApi(Retrofit retrofit) {
+        return retrofit.create(CategoryApi.class);
+    }
+}

android/app/src/main/java/com/example/petstoremobile/fragments/ChatFragment.java

@@ -26,7 +26,6 @@ import com.example.petstoremobile.api.auth.TokenManager;
 import com.example.petstoremobile.api.ChatApi;
 import com.example.petstoremobile.api.CustomerApi;
 import com.example.petstoremobile.api.MessageApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.ConversationDTO;
 import com.example.petstoremobile.dtos.CustomerDTO;
 import com.example.petstoremobile.dtos.MessageDTO;
@@ -36,10 +35,17 @@ import com.example.petstoremobile.models.Chat;
 import com.example.petstoremobile.models.Message;
 import com.example.petstoremobile.services.ChatNotificationService;
 import com.example.petstoremobile.websocket.StompChatManager;
+
 import java.util.*;
 import java.util.stream.Collectors;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickListener, StompChatManager.MessageListener,
         StompChatManager.ConversationListener, StompChatManager.ConnectionListener {
 
@@ -70,9 +76,11 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
     private Uri pendingAttachmentUri;
 
     // APIs
-    private ChatApi chatApi;
+    @Inject ChatApi chatApi;
-    private CustomerApi customerApi;
+    @Inject CustomerApi customerApi;
-    private MessageApi messageApi;
+    @Inject MessageApi messageApi;
+    @Inject TokenManager tokenManager;
+    @Inject @Named("baseUrl") String baseUrl;
 
     // chat
     private Long currentUserId;
@@ -103,10 +111,6 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
 
         View view = inflater.inflate(R.layout.fragment_chat, container, false);
 
-        chatApi = RetrofitClient.getChatApi(requireContext());
-        customerApi = RetrofitClient.getCustomerApi(requireContext());
-        messageApi = RetrofitClient.getMessageApi(requireContext());
-
         drawerLayout = view.findViewById(R.id.chatDrawerLayout);
         rvChatList = view.findViewById(R.id.rvChatList);
         rvMessages = view.findViewById(R.id.rvMessages);
@@ -169,16 +173,15 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
 
     //Helper function to load token and user id then connect to websocket
     private void loadInitialData() {
-        TokenManager tm = TokenManager.getInstance(requireContext());
+        String token = tokenManager.getToken();
-        String token = tm.getToken();
+        currentUserId = tokenManager.getUserId();
-        currentUserId = tm.getUserId();
+        String role = tokenManager.getRole();
-        String role = tm.getRole();
 
         messageAdapter.setCurrentUserId(currentUserId);
 
         // if token exist then connect to websocket
         if (token != null) {
-            stompChatManager = new StompChatManager(token, role);
+            stompChatManager = new StompChatManager(token, role, baseUrl);
             stompChatManager.setMessageListener(this);
             stompChatManager.setConversationListener(this);
             stompChatManager.setConnectionListener(this);
@@ -561,4 +564,4 @@ public class ChatFragment extends Fragment implements ChatAdapter.OnChatClickLis
         ChatNotificationService.activeConversationIdInUi = null;
         if (stompChatManager != null) stompChatManager.disconnect();
     }
-}
+}

android/app/src/main/java/com/example/petstoremobile/fragments/ListFragment.java

@@ -26,7 +26,12 @@ import com.example.petstoremobile.fragments.listfragments.ProductSupplierFragmen
 import com.example.petstoremobile.fragments.listfragments.PurchaseOrderFragment;
 import com.example.petstoremobile.fragments.listfragments.SaleFragment;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
+
 //The Fragment for the displaying the list of entities to be viewed
+@AndroidEntryPoint
 public class ListFragment extends Fragment {
 
     private DrawerLayout drawerLayout;
@@ -37,6 +42,7 @@ public class ListFragment extends Fragment {
 
     private LinearLayout drawerAdoptions, drawerAppointments, drawerInventory, drawerProducts, drawerProductSupplier, drawerPurchaseOrderView, drawerSale;
 
+    @Inject TokenManager tokenManager;
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
@@ -58,7 +64,7 @@ public class ListFragment extends Fragment {
 
 
         // Check user role and restrict access for STAFF
-        String role = TokenManager.getInstance(requireContext()).getRole();
+        String role = tokenManager.getRole();
         if ("STAFF".equalsIgnoreCase(role)) {
             drawerSuppliers.setVisibility(View.GONE);
             drawerInventory.setVisibility(View.GONE);
@@ -178,4 +184,4 @@ public class ListFragment extends Fragment {
                 .addToBackStack(null)
                 .commit();
     }
-}
+}

android/app/src/main/java/com/example/petstoremobile/fragments/ProfileFragment.java

@@ -32,7 +32,6 @@ import com.bumptech.glide.load.model.GlideUrl;
 import com.bumptech.glide.load.model.LazyHeaders;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.activities.MainActivity;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.auth.AuthApi;
 import com.example.petstoremobile.api.auth.TokenManager;
 import com.example.petstoremobile.dtos.ErrorResponse;
@@ -49,6 +48,10 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import okhttp3.MediaType;
 import okhttp3.MultipartBody;
 import okhttp3.RequestBody;
@@ -56,6 +59,7 @@ import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class ProfileFragment extends Fragment {
 
     //initialize the view/controls
@@ -65,6 +69,10 @@ public class ProfileFragment extends Fragment {
     private UserDTO currentUser;
     private boolean hasImage = false;
 
+    @Inject AuthApi authApi;
+    @Inject TokenManager tokenManager;
+    @Inject @Named("baseUrl") String baseUrl;
+
     //Initialize the launchers for camera and gallery
     private ActivityResultLauncher<Intent> galleryLauncher;
     private ActivityResultLauncher<Uri> cameraLauncher;
@@ -251,7 +259,7 @@ public class ProfileFragment extends Fragment {
             Intent serviceIntent = new Intent(requireContext(), ChatNotificationService.class);
             requireContext().stopService(serviceIntent);
 
-            TokenManager.getInstance(requireContext()).clearLoginData(); // clear the token for next login
+            tokenManager.clearLoginData(); // clear the token for next login
             //get the intent to the main activity and clear the back stack so the back button won't allow the user to go back to the previous screen
             Intent intent = new Intent(getActivity(), MainActivity.class);
             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);
@@ -275,8 +283,6 @@ public class ProfileFragment extends Fragment {
 
     //Helper function to call the backend to get profile data and load it to the view
     private void loadProfileData() {
-        AuthApi authApi = RetrofitClient.getAuthApi(requireContext());
-
         authApi.getMe().enqueue(new Callback<UserDTO>() {
             @Override
             public void onResponse(Call<UserDTO> call, Response<UserDTO> response) {
@@ -291,8 +297,8 @@ public class ProfileFragment extends Fragment {
                     tvProfileRole.setText(currentUser.getRole());
 
                     // get the avatar endpoint to load profile image and the token for authorization
-                    String avatarUrl = RetrofitClient.BASE_URL + AuthApi.AVATAR_FILE_PATH;
+                    String avatarUrl = baseUrl + AuthApi.AVATAR_FILE_PATH;
-                    String token = TokenManager.getInstance(requireContext()).getToken();
+                    String token = tokenManager.getToken();
 
                     if (token != null) {
                         // Create GlideUrl with token to fetch the image
@@ -354,7 +360,6 @@ public class ProfileFragment extends Fragment {
             MultipartBody.Part body = MultipartBody.Part.createFormData("avatar", file.getName(), requestFile);
 
             //Call the backend to upload the avatar
-            AuthApi authApi = RetrofitClient.getAuthApi(requireContext());
             authApi.uploadAvatar(body).enqueue(new Callback<UserDTO>() {
                 @Override
                 public void onResponse(Call<UserDTO> call, Response<UserDTO> response) {
@@ -380,7 +385,6 @@ public class ProfileFragment extends Fragment {
     }
 
     private void deleteAvatar() {
-        AuthApi authApi = RetrofitClient.getAuthApi(requireContext());
         authApi.deleteAvatar().enqueue(new Callback<Void>() {
             @Override
             public void onResponse(Call<Void> call, Response<Void> response) {
@@ -423,7 +427,6 @@ public class ProfileFragment extends Fragment {
 
     //Helper function to update a profile field in the backend
     private void updateProfileField(String fieldName, String value) {
-        AuthApi authApi = RetrofitClient.getAuthApi(requireContext());
         Map<String, String> updates = new HashMap<>();
         updates.put(fieldName, value);
 
@@ -456,4 +459,4 @@ public class ProfileFragment extends Fragment {
             }
         });
     }
-}
+}

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

@@ -14,7 +14,6 @@ import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.AdoptionAdapter;
 import com.example.petstoremobile.api.AdoptionApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.AdoptionDTO;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.fragments.ListFragment;
@@ -28,14 +27,19 @@ import com.prolificinteractive.materialcalendarview.OnDateSelectedListener;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdoptionClickListener {
 
     private List<AdoptionDTO> adoptionList = new ArrayList<>();
     private List<AdoptionDTO> filteredList = new ArrayList<>();
     private AdoptionAdapter adapter;
-    private AdoptionApi api;
+    @Inject AdoptionApi api;
     private SwipeRefreshLayout swipeRefresh;
     private EditText etSearch;
     private ImageButton hamburger;
@@ -50,7 +54,6 @@ public class AdoptionFragment extends Fragment implements AdoptionAdapter.OnAdop
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_adoption, container, false);
 
-        api = RetrofitClient.getAdoptionApi(requireContext());
         hamburger = view.findViewById(R.id.btnHamburgerAdoption);
         calendarView = view.findViewById(R.id.calendarViewAdoption);
         btnToggleCalendarMode = view.findViewById(R.id.btnToggleCalendarModeAdoption);

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

@@ -23,7 +23,6 @@ import com.example.petstoremobile.adapters.AppointmentAdapter;
 import com.example.petstoremobile.api.AppointmentApi;
 import com.example.petstoremobile.api.PetApi;
 import com.example.petstoremobile.api.ServiceApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.AppointmentDTO;
 import com.example.petstoremobile.dtos.ServiceDTO;
 import com.example.petstoremobile.dtos.PageResponse;
@@ -46,10 +45,14 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class AppointmentFragment extends Fragment implements AppointmentAdapter.OnAppointmentClickListener {
 
     private List<AppointmentDTO> appointmentList = new ArrayList<>();
@@ -58,7 +61,10 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
     private List<ServiceDTO> serviceList = new ArrayList<>();
 
     private AppointmentAdapter adapter;
-    private AppointmentApi api;
+    @Inject AppointmentApi api;
+    @Inject PetApi petApi;
+    @Inject ServiceApi serviceApi;
+
     private SwipeRefreshLayout swipeRefreshLayout;
     private EditText etSearch;
     private ImageButton hamburger;
@@ -73,7 +79,6 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_appointment, container, false);
 
-        api = RetrofitClient.getAppointmentApi(requireContext());
         hamburger = view.findViewById(R.id.btnHamburger);
         calendarView = view.findViewById(R.id.calendarView);
         btnToggleCalendarMode = view.findViewById(R.id.btnToggleCalendarMode);
@@ -267,7 +272,6 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
 
     // Load Pets
     private void loadPets() {
-        PetApi petApi = RetrofitClient.getPetApi(requireContext());
         petApi.getAllPets(0,100).enqueue(new Callback<PageResponse<PetDTO>>() {
 
             @Override
@@ -290,8 +294,6 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
     // Load Services
 
     private void loadServices() {
-        ServiceApi serviceApi = RetrofitClient.getServiceApi(requireContext());
-
         serviceApi.getAllServices(0,100).enqueue(new Callback<PageResponse<ServiceDTO>>() {
             @Override
             public void onResponse(Call<PageResponse<ServiceDTO>> call, Response<PageResponse<ServiceDTO>> response) {
@@ -331,4 +333,4 @@ public class AppointmentFragment extends Fragment implements AppointmentAdapter.
         recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
         recyclerView.setAdapter(adapter);
     }
-}
+}

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

@@ -10,7 +10,6 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.AdapterView;
-import android.widget.ArrayAdapter;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.ImageButton;
@@ -28,7 +27,6 @@ import com.example.petstoremobile.adapters.BlackTextArrayAdapter;
 import com.example.petstoremobile.adapters.InventoryAdapter;
 import com.example.petstoremobile.api.CategoryApi;
 import com.example.petstoremobile.api.InventoryApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.BulkDeleteRequest;
 import com.example.petstoremobile.dtos.CategoryDTO;
 import com.example.petstoremobile.dtos.InventoryDTO;
@@ -40,10 +38,14 @@ import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class InventoryFragment extends Fragment implements InventoryAdapter.OnInventoryClickListener {
 
     private static final String TAG = "InventoryFragment";
@@ -52,8 +54,8 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
     private final List<InventoryDTO> inventoryList = new ArrayList<>();
     private final List<CategoryDTO> categoryList = new ArrayList<>();
     private InventoryAdapter adapter;
-    private InventoryApi inventoryApi;
+    @Inject InventoryApi inventoryApi;
-    private CategoryApi categoryApi;
+    @Inject CategoryApi categoryApi;
 
     private SwipeRefreshLayout swipeRefreshLayout;
     private EditText etSearch;
@@ -83,9 +85,6 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_inventory, container, false);
 
-        inventoryApi = RetrofitClient.getInventoryApi(requireContext());
-        categoryApi = RetrofitClient.getCategoryApi(requireContext());
-
         hamburger = view.findViewById(R.id.btnHamburger);
         btnBulkDelete = view.findViewById(R.id.btnBulkDelete);
         tvSelectionCount = view.findViewById(R.id.tvSelectionCount);
@@ -175,8 +174,7 @@ public class InventoryFragment extends Fragment implements InventoryAdapter.OnIn
     private void setupSearch(View view) {
         etSearch = view.findViewById(R.id.etSearchInventory);
         etSearch.addTextChangedListener(new TextWatcher() {
-            @Override
+            @Override public void beforeTextChanged(CharSequence s, int i, int i1, int i2) {
-            public void beforeTextChanged(CharSequence s, int i, int i1, int i2) {
             }
 
             @Override

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

@@ -14,7 +14,6 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.AdapterView;
-import android.widget.ArrayAdapter;
 import android.widget.EditText;
 import android.widget.ImageButton;
 import android.widget.Spinner;
@@ -24,7 +23,6 @@ import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.BlackTextArrayAdapter;
 import com.example.petstoremobile.adapters.PetAdapter;
 import com.example.petstoremobile.api.PetApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.dtos.PetDTO;
 import com.example.petstoremobile.fragments.ListFragment;
@@ -35,16 +33,22 @@ import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class PetFragment extends Fragment implements PetAdapter.OnPetClickListener {
     private List<PetDTO> petList = new ArrayList<>();
     private List<PetDTO> filteredList = new ArrayList<>();
     private ImageButton hamburger;
     private PetAdapter adapter;
-    private PetApi api;
+    @Inject PetApi api;
+    @Inject @Named("baseUrl") String baseUrl;
     private SwipeRefreshLayout swipeRefreshLayout;
     private EditText etSearch;
     private Spinner spinnerStatus;
@@ -55,9 +59,6 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_pet, container, false);
 
-        //get retrofit
-        api = RetrofitClient.getPetApi(requireContext());
-
         hamburger = view.findViewById(R.id.btnHamburger);
 
         setupRecyclerView(view);
@@ -231,6 +232,7 @@ public class PetFragment extends Fragment implements PetAdapter.OnPetClickListen
     private void setupRecyclerView(View view) {
         RecyclerView recyclerView = view.findViewById(R.id.recyclerViewPets);
         adapter = new PetAdapter(filteredList, this);
+        adapter.setBaseUrl(baseUrl);
         recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
         recyclerView.setAdapter(adapter);
     }

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

@@ -11,15 +11,20 @@ import androidx.recyclerview.widget.RecyclerView;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.ProductAdapter;
-import com.example.petstoremobile.api.RetrofitClient;
+import com.example.petstoremobile.api.ProductApi;
 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.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class ProductFragment extends Fragment implements ProductAdapter.OnProductClickListener {
 
     private List<ProductDTO> productList = new ArrayList<>();
@@ -28,6 +33,8 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
     private SwipeRefreshLayout swipeRefresh;
     private EditText etSearch;
 
+    @Inject ProductApi api;
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -93,7 +100,7 @@ public class ProductFragment extends Fragment implements ProductAdapter.OnProduc
 
     private void loadProducts() {
         if (swipeRefresh != null) swipeRefresh.setRefreshing(true);
-        RetrofitClient.getProductApi(requireContext()).getAllProducts(null, 0, 100)
+        api.getAllProducts(null, 0, 100)
                 .enqueue(new Callback<PageResponse<ProductDTO>>() {
                     public void onResponse(Call<PageResponse<ProductDTO>> c,
                                            Response<PageResponse<ProductDTO>> r) {

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

@@ -11,15 +11,20 @@ import androidx.recyclerview.widget.RecyclerView;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.ProductSupplierAdapter;
-import com.example.petstoremobile.api.RetrofitClient;
+import com.example.petstoremobile.api.ProductSupplierApi;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.dtos.ProductSupplierDTO;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.detailfragments.ProductSupplierDetailFragment;
 import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class ProductSupplierFragment extends Fragment
         implements ProductSupplierAdapter.OnProductSupplierClickListener {
 
@@ -29,6 +34,8 @@ public class ProductSupplierFragment extends Fragment
     private SwipeRefreshLayout swipeRefresh;
     private EditText etSearch;
 
+    @Inject ProductSupplierApi api;
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -92,7 +99,7 @@ public class ProductSupplierFragment extends Fragment
 
     private void loadData() {
         if (swipeRefresh != null) swipeRefresh.setRefreshing(true);
-        RetrofitClient.getProductSupplierApi(requireContext()).getAllProductSuppliers(0, 100)
+        api.getAllProductSuppliers(0, 100)
                 .enqueue(new Callback<PageResponse<ProductSupplierDTO>>() {
                     public void onResponse(Call<PageResponse<ProductSupplierDTO>> c,
                                            Response<PageResponse<ProductSupplierDTO>> r) {

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

@@ -11,14 +11,19 @@ import androidx.recyclerview.widget.RecyclerView;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.PurchaseOrderAdapter;
-import com.example.petstoremobile.api.RetrofitClient;
+import com.example.petstoremobile.api.PurchaseOrderApi;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.dtos.PurchaseOrderDTO;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.detailfragments.PurchaseOrderDetailFragment;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class PurchaseOrderFragment extends Fragment
         implements PurchaseOrderAdapter.OnPurchaseOrderClickListener {
 
@@ -28,6 +33,8 @@ public class PurchaseOrderFragment extends Fragment
     private SwipeRefreshLayout swipeRefresh;
     private EditText etSearch;
 
+    @Inject PurchaseOrderApi api;
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -94,7 +101,7 @@ public class PurchaseOrderFragment extends Fragment
     private void loadData() {
         if (swipeRefresh != null)
             swipeRefresh.setRefreshing(true);
-        RetrofitClient.getPurchaseOrderApi(requireContext()).getAllPurchaseOrders(0, 100)
+        api.getAllPurchaseOrders(0, 100)
                 .enqueue(new Callback<PageResponse<PurchaseOrderDTO>>() {
                     public void onResponse(Call<PageResponse<PurchaseOrderDTO>> c,
                                            Response<PageResponse<PurchaseOrderDTO>> r) {

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

@@ -15,12 +15,18 @@ import android.widget.ImageButton;
 
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.SaleAdapter;
+import com.example.petstoremobile.api.SaleApi;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.detailfragments.RefundDetailFragment;
 import com.example.petstoremobile.models.Sale;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
+
+@AndroidEntryPoint
 public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickListener {
 
     private List<Sale> saleList = new ArrayList<>();
@@ -30,6 +36,8 @@ public class SaleFragment extends Fragment implements SaleAdapter.OnSaleClickLis
     private EditText etSearch;
     private ImageButton btnHamburger;
 
+    @Inject SaleApi api;
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {

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

@@ -19,7 +19,6 @@ import android.widget.Toast;
 
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.ServiceAdapter;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.ServiceApi;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.dtos.ServiceDTO;
@@ -30,17 +29,21 @@ import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class ServiceFragment extends Fragment implements ServiceAdapter.OnServiceClickListener {
 
     private List<ServiceDTO> serviceList = new ArrayList<>();
     private List<ServiceDTO> filteredList = new ArrayList<>();
     private ServiceAdapter adapter;
     private ImageButton hamburger;
-    private ServiceApi api;
+    @Inject ServiceApi api;
     private SwipeRefreshLayout swipeRefreshLayout;
     private EditText etSearch;
 
@@ -50,7 +53,6 @@ public class ServiceFragment extends Fragment implements ServiceAdapter.OnServic
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_service, container, false);
 
-        api = RetrofitClient.getServiceApi(requireContext());
         hamburger = view.findViewById(R.id.btnHamburger);
 
         setupRecyclerView(view);

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

@@ -19,7 +19,6 @@ import android.widget.Toast;
 
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.SupplierAdapter;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.SupplierApi;
 import com.example.petstoremobile.dtos.PageResponse;
 import com.example.petstoremobile.dtos.SupplierDTO;
@@ -30,17 +29,21 @@ import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupplierClickListener {
 
     private List<SupplierDTO> supplierList = new ArrayList<>();
     private List<SupplierDTO> filteredList = new ArrayList<>();
     private SupplierAdapter adapter;
     private ImageButton hamburger;
-    private SupplierApi api;
+    @Inject SupplierApi api;
     private SwipeRefreshLayout swipeRefreshLayout;
     private EditText etSearch;
 
@@ -50,7 +53,6 @@ public class SupplierFragment extends Fragment implements SupplierAdapter.OnSupp
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_supplier, container, false);
 
-        api = RetrofitClient.getSupplierApi(requireContext());
         hamburger = view.findViewById(R.id.btnHamburger);
 
         setupRecyclerView(view);

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

@@ -14,8 +14,13 @@ import com.example.petstoremobile.api.*;
 import com.example.petstoremobile.dtos.*;
 import com.example.petstoremobile.fragments.ListFragment;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class AdoptionDetailFragment extends Fragment {
 
     private TextView tvMode, tvAdoptionId;
@@ -33,6 +38,10 @@ public class AdoptionDetailFragment extends Fragment {
 
     private final String[] STATUSES = {"Pending", "Approved", "Rejected"};
 
+    @Inject AdoptionApi adoptionApi;
+    @Inject PetApi petApi;
+    @Inject CustomerApi customerApi;
+
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -84,7 +93,7 @@ public class AdoptionDetailFragment extends Fragment {
     }
 
     private void loadPets() {
-        RetrofitClient.getPetApi(requireContext()).getAllPets(0, 200)
+        petApi.getAllPets(0, 200)
                 .enqueue(new Callback<PageResponse<PetDTO>>() {
                     public void onResponse(Call<PageResponse<PetDTO>> c,
                                            Response<PageResponse<PetDTO>> r) {
@@ -115,7 +124,7 @@ public class AdoptionDetailFragment extends Fragment {
     }
 
     private void loadCustomers() {
-        RetrofitClient.getCustomerApi(requireContext()).getAllCustomers(0, 200)
+        customerApi.getAllCustomers(0, 200)
                 .enqueue(new Callback<PageResponse<CustomerDTO>>() {
                     public void onResponse(Call<PageResponse<CustomerDTO>> c,
                                            Response<PageResponse<CustomerDTO>> r) {
@@ -201,11 +210,10 @@ public class AdoptionDetailFragment extends Fragment {
                 + " customerId=" + customer.getCustomerId()
                 + " date=" + date + " status=" + status);
 
-        AdoptionApi api = RetrofitClient.getAdoptionApi(requireContext());
         if (isEditing) {
-            api.updateAdoption(adoptionId, dto).enqueue(simpleCallback("Updated"));
+            adoptionApi.updateAdoption(adoptionId, dto).enqueue(simpleCallback("Updated"));
         } else {
-            api.createAdoption(dto).enqueue(simpleCallback("Saved"));
+            adoptionApi.createAdoption(dto).enqueue(simpleCallback("Saved"));
         }
     }
 
@@ -237,8 +245,7 @@ public class AdoptionDetailFragment extends Fragment {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Delete Adoption?")
                 .setPositiveButton("Yes", (d, w) ->
-                        RetrofitClient.getAdoptionApi(requireContext())
+                        adoptionApi.deleteAdoption(adoptionId)
-                                .deleteAdoption(adoptionId)
                                 .enqueue(new Callback<Void>() {
                                     public void onResponse(Call<Void> c, Response<Void> r) {
                                         navigateBack();

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

@@ -14,8 +14,13 @@ import com.example.petstoremobile.api.*;
 import com.example.petstoremobile.dtos.*;
 import com.example.petstoremobile.fragments.ListFragment;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class AppointmentDetailFragment extends Fragment {
 
     private TextView tvMode, tvAppointmentId;
@@ -41,6 +46,12 @@ public class AppointmentDetailFragment extends Fragment {
     private final Integer[] MINUTES = {0,15,30,45};
     private final String[] STATUSES = {"Booked","Completed","Cancelled"};
 
+    @Inject AppointmentApi appointmentApi;
+    @Inject PetApi petApi;
+    @Inject ServiceApi serviceApi;
+    @Inject CustomerApi customerApi;
+    @Inject StoreApi storeApi;
+
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_appointment_detail, container, false);
@@ -107,7 +118,7 @@ public class AppointmentDetailFragment extends Fragment {
     }
 
     private void loadPets() {
-        RetrofitClient.getPetApi(requireContext()).getAllPets(0, 200)
+        petApi.getAllPets(0, 200)
                 .enqueue(new Callback<PageResponse<PetDTO>>() {
                     public void onResponse(Call<PageResponse<PetDTO>> c, Response<PageResponse<PetDTO>> r) {
                         if (r.isSuccessful() && r.body() != null) {
@@ -137,7 +148,7 @@ public class AppointmentDetailFragment extends Fragment {
     }
 
     private void loadServices() {
-        RetrofitClient.getServiceApi(requireContext()).getAllServices(0, 200)
+        serviceApi.getAllServices(0, 200)
                 .enqueue(new Callback<PageResponse<ServiceDTO>>() {
                     public void onResponse(Call<PageResponse<ServiceDTO>> c, Response<PageResponse<ServiceDTO>> r) {
                         if (r.isSuccessful() && r.body() != null) {
@@ -167,7 +178,7 @@ public class AppointmentDetailFragment extends Fragment {
     }
 
     private void loadCustomers() {
-        RetrofitClient.getCustomerApi(requireContext()).getAllCustomers(0, 200)
+        customerApi.getAllCustomers(0, 200)
                 .enqueue(new Callback<PageResponse<CustomerDTO>>() {
                     public void onResponse(Call<PageResponse<CustomerDTO>> c, Response<PageResponse<CustomerDTO>> r) {
                         if (r.isSuccessful() && r.body() != null) {
@@ -198,7 +209,7 @@ public class AppointmentDetailFragment extends Fragment {
     }
 
     private void loadStores() {
-        RetrofitClient.getStoreApi(requireContext()).getAllStores(0, 50)
+        storeApi.getAllStores(0, 50)
                 .enqueue(new Callback<PageResponse<StoreDTO>>() {
                     public void onResponse(Call<PageResponse<StoreDTO>> c, Response<PageResponse<StoreDTO>> r) {
                         if (r.isSuccessful() && r.body() != null) {
@@ -228,7 +239,7 @@ public class AppointmentDetailFragment extends Fragment {
     }
 
     private void loadAllAppointments() {
-        RetrofitClient.getAppointmentApi(requireContext()).getAllAppointments(0, 500)
+        appointmentApi.getAllAppointments(0, 500)
                 .enqueue(new Callback<PageResponse<AppointmentDTO>>() {
                     public void onResponse(Call<PageResponse<AppointmentDTO>> c, Response<PageResponse<AppointmentDTO>> r) {
                         if (r.isSuccessful() && r.body() != null)
@@ -350,11 +361,10 @@ public class AppointmentDetailFragment extends Fragment {
                 + " petId=" + pet.getPetId()
                 + " date=" + date + " time=" + time);
 
-        AppointmentApi api = RetrofitClient.getAppointmentApi(requireContext());
         if (isEditing) {
-            api.updateAppointment(appointmentId, dto).enqueue(simpleCallback("Updated"));
+            appointmentApi.updateAppointment(appointmentId, dto).enqueue(simpleCallback("Updated"));
         } else {
-            api.createAppointment(dto).enqueue(simpleCallback("Saved"));
+            appointmentApi.createAppointment(dto).enqueue(simpleCallback("Saved"));
         }
     }
 
@@ -426,8 +436,7 @@ public class AppointmentDetailFragment extends Fragment {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Delete Appointment?")
                 .setPositiveButton("Yes", (d, w) ->
-                        RetrofitClient.getAppointmentApi(requireContext())
+                        appointmentApi.deleteAppointment(appointmentId)
-                                .deleteAppointment(appointmentId)
                                 .enqueue(new Callback<Void>() {
                                     public void onResponse(Call<Void> c, Response<Void> r) { navigateBack(); }
                                     public void onFailure(Call<Void> c, Throwable t) {

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

@@ -21,7 +21,6 @@ import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.BlackTextArrayAdapter;
 import com.example.petstoremobile.api.InventoryApi;
 import com.example.petstoremobile.api.ProductApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.InventoryDTO;
 import com.example.petstoremobile.dtos.InventoryRequest;
 import com.example.petstoremobile.dtos.PageResponse;
@@ -32,10 +31,14 @@ import com.example.petstoremobile.fragments.listfragments.InventoryFragment;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class InventoryDetailFragment extends Fragment {
 
     private TextView tvMode, tvInventoryId, tvProductInfo;
@@ -43,8 +46,8 @@ public class InventoryDetailFragment extends Fragment {
     private android.widget.EditText etQuantity;
     private Button btnSave, btnDelete, btnBack;
 
-    private InventoryApi inventoryApi;
+    @Inject InventoryApi inventoryApi;
-    private ProductApi productApi;
+    @Inject ProductApi productApi;
     private InventoryFragment inventoryFragment;
 
     private boolean isEditing = false;
@@ -70,9 +73,6 @@ public class InventoryDetailFragment extends Fragment {
                              Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.fragment_inventory_detail, container, false);
 
-        inventoryApi = RetrofitClient.getInventoryApi(requireContext());
-        productApi = RetrofitClient.getProductApi(requireContext());
-
         initViews(view);
         setupProductSearch();
         handleArguments();

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

@@ -22,17 +22,20 @@ import android.widget.Toast;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.BlackTextArrayAdapter;
 import com.example.petstoremobile.api.PetApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.PetDTO;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.PetFragment;
 import com.example.petstoremobile.utils.ActivityLogger;
 import com.example.petstoremobile.utils.InputValidator;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class PetDetailFragment extends Fragment {
 
     private TextView tvMode, tvPetId;
@@ -43,6 +46,8 @@ public class PetDetailFragment extends Fragment {
     private boolean isEditing = false;
     private PetFragment petFragment;
 
+    @Inject PetApi petApi;
+
     //set the pet fragment to the parent so we refer back to pet view when save or delete is done
     public void setPetFragment(PetFragment fragment) {
         this.petFragment = fragment;
@@ -92,8 +97,6 @@ public class PetDetailFragment extends Fragment {
         petDTO.setPetPrice(priceStr);
         petDTO.setPetStatus(status);
 
-        PetApi petApi = RetrofitClient.getPetApi(requireContext());
-
         //check if the pet is being edited or added
         if (isEditing) {
             // Update existing pet
@@ -148,7 +151,6 @@ public class PetDetailFragment extends Fragment {
                 .setTitle("Delete Pet")
                 .setMessage("Are you sure you want to delete " + etPetName.getText().toString() + "?")
                 .setPositiveButton("Delete", (dialog, which) -> {
-                    PetApi petApi = RetrofitClient.getPetApi(requireContext());
                     //if they say yes then delete the pet
                     petApi.deletePet((long) petId).enqueue(new Callback<Void>() {
                         @Override
@@ -242,4 +244,4 @@ public class PetDetailFragment extends Fragment {
         spinnerPetStatus.setAdapter(adapter);
     }
 
-}
+}

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

@@ -29,11 +29,17 @@ import java.io.FileOutputStream;
 import java.io.InputStream;
 import java.math.BigDecimal;
 import java.util.*;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import okhttp3.MediaType;
 import okhttp3.MultipartBody;
 import okhttp3.RequestBody;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class ProductDetailFragment extends Fragment {
 
     private TextView tvMode, tvProductId;
@@ -50,6 +56,10 @@ public class ProductDetailFragment extends Fragment {
     private List<CategoryDTO> categoryList = new ArrayList<>();
     private Uri photoUri;
 
+    @Inject ProductApi productApi;
+    @Inject CategoryApi categoryApi;
+    @Inject @Named("baseUrl") String baseUrl;
+
     private ActivityResultLauncher<Intent> galleryLauncher;
     private ActivityResultLauncher<Uri> cameraLauncher;
     private ActivityResultLauncher<String> permissionLauncher;
@@ -155,7 +165,7 @@ public class ProductDetailFragment extends Fragment {
     // Helper function to remove the photo
     private void removePhoto() {
         if (isEditing) {
-            RetrofitClient.getProductApi(requireContext()).deleteProductImage(prodId)
+            productApi.deleteProductImage(prodId)
                     .enqueue(new Callback<Void>() {
                         @Override
                         public void onResponse(Call<Void> call, Response<Void> response) {
@@ -187,7 +197,7 @@ public class ProductDetailFragment extends Fragment {
     }
 
     private void loadCategories() {
-        RetrofitClient.getCategoryApi(requireContext()).getAllCategories(0, 100)
+        categoryApi.getAllCategories(0, 100)
                 .enqueue(new Callback<PageResponse<CategoryDTO>>() {
                     public void onResponse(Call<PageResponse<CategoryDTO>> c,
                                            Response<PageResponse<CategoryDTO>> r) {
@@ -243,7 +253,7 @@ public class ProductDetailFragment extends Fragment {
 
     //load the product image from the backend
     private void loadProductImage() {
-        String imageUrl = RetrofitClient.BASE_URL + String.format(Locale.US, ProductApi.PRODUCT_IMAGE_PATH, prodId);
+        String imageUrl = baseUrl + String.format(Locale.US, ProductApi.PRODUCT_IMAGE_PATH, prodId);
         Glide.with(this)
                 .load(imageUrl)
                 .diskCacheStrategy(DiskCacheStrategy.NONE)
@@ -262,7 +272,7 @@ public class ProductDetailFragment extends Fragment {
             RequestBody requestFile = RequestBody.create(file, MediaType.parse(requireContext().getContentResolver().getType(uri)));
             MultipartBody.Part body = MultipartBody.Part.createFormData("image", file.getName(), requestFile);
 
-            RetrofitClient.getProductApi(requireContext()).uploadProductImage(prodId, body)
+            productApi.uploadProductImage(prodId, body)
                     .enqueue(new Callback<Void>() {
                         @Override
                         public void onResponse(Call<Void> call, Response<Void> response) {
@@ -328,11 +338,10 @@ public class ProductDetailFragment extends Fragment {
 
         ProductDTO dto = new ProductDTO(name, category.getCategoryId(), desc, price);
 
-        ProductApi api = RetrofitClient.getProductApi(requireContext());
         if (isEditing) {
-            api.updateProduct(prodId, dto).enqueue(simpleCallback("Updated"));
+            productApi.updateProduct(prodId, dto).enqueue(simpleCallback("Updated"));
         } else {
-            api.createProduct(dto).enqueue(new Callback<ProductDTO>() {
+            productApi.createProduct(dto).enqueue(new Callback<ProductDTO>() {
                 @Override
                 public void onResponse(Call<ProductDTO> call, Response<ProductDTO> response) {
                     if (response.isSuccessful() && response.body() != null) {
@@ -375,8 +384,7 @@ public class ProductDetailFragment extends Fragment {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Delete Product?")
                 .setPositiveButton("Yes", (d, w) ->
-                        RetrofitClient.getProductApi(requireContext())
+                        productApi.deleteProduct(prodId)
-                                .deleteProduct(prodId)
                                 .enqueue(new Callback<Void>() {
                                     public void onResponse(Call<Void> c, Response<Void> r) {
                                         navigateBack();

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

@@ -14,8 +14,13 @@ import com.example.petstoremobile.dtos.*;
 import com.example.petstoremobile.fragments.ListFragment;
 import java.math.BigDecimal;
 import java.util.*;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.*;
 
+@AndroidEntryPoint
 public class ProductSupplierDetailFragment extends Fragment {
 
     private TextView tvMode;
@@ -32,6 +37,10 @@ public class ProductSupplierDetailFragment extends Fragment {
     private List<ProductDTO> productList = new ArrayList<>();
     private List<SupplierDTO> supplierList = new ArrayList<>();
 
+    @Inject ProductSupplierApi productSupplierApi;
+    @Inject ProductApi productApi;
+    @Inject SupplierApi supplierApi;
+
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -62,7 +71,7 @@ public class ProductSupplierDetailFragment extends Fragment {
     }
 
     private void loadProducts() {
-        RetrofitClient.getProductApi(requireContext()).getAllProducts(null, 0, 200)
+        productApi.getAllProducts(null, 0, 200)
                 .enqueue(new Callback<PageResponse<ProductDTO>>() {
                     public void onResponse(Call<PageResponse<ProductDTO>> c,
                                            Response<PageResponse<ProductDTO>> r) {
@@ -93,7 +102,7 @@ public class ProductSupplierDetailFragment extends Fragment {
     }
 
     private void loadSuppliers() {
-        RetrofitClient.getSupplierApi(requireContext()).getAllSuppliers(0, 200)
+        supplierApi.getAllSuppliers(0, 200)
                 .enqueue(new Callback<PageResponse<SupplierDTO>>() {
                     public void onResponse(Call<PageResponse<SupplierDTO>> c,
                                            Response<PageResponse<SupplierDTO>> r) {
@@ -164,12 +173,11 @@ public class ProductSupplierDetailFragment extends Fragment {
         ProductSupplierDTO dto = new ProductSupplierDTO(
                 product.getProdId(), supplier.getSupId(), cost);
 
-        ProductSupplierApi api = RetrofitClient.getProductSupplierApi(requireContext());
         if (isEditing) {
-            api.updateProductSupplier(editProductId, editSupplierId, dto)
+            productSupplierApi.updateProductSupplier(editProductId, editSupplierId, dto)
                     .enqueue(simpleCallback("Updated"));
         } else {
-            api.createProductSupplier(dto).enqueue(simpleCallback("Saved"));
+            productSupplierApi.createProductSupplier(dto).enqueue(simpleCallback("Saved"));
         }
     }
 
@@ -200,8 +208,7 @@ public class ProductSupplierDetailFragment extends Fragment {
         new AlertDialog.Builder(requireContext())
                 .setTitle("Delete?")
                 .setPositiveButton("Yes", (d, w) ->
-                        RetrofitClient.getProductSupplierApi(requireContext())
+                        productSupplierApi.deleteProductSupplier(editProductId, editSupplierId)
-                                .deleteProductSupplier(editProductId, editSupplierId)
                                 .enqueue(new Callback<Void>() {
                                     public void onResponse(Call<Void> c, Response<Void> r) {
                                         navigateBack();

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

@@ -9,6 +9,9 @@ import androidx.fragment.app.Fragment;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.fragments.ListFragment;
 
+import dagger.hilt.android.AndroidEntryPoint;
+
+@AndroidEntryPoint
 public class PurchaseOrderDetailFragment extends Fragment {
 
     private TextView tvId, tvSupplier, tvDate, tvStatus;

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

@@ -13,11 +13,17 @@ import android.widget.TextView;
 import android.widget.Toast;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.adapters.BlackTextArrayAdapter;
+import com.example.petstoremobile.api.SaleApi;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.SaleFragment;
 import com.example.petstoremobile.utils.ActivityLogger;
 import com.example.petstoremobile.utils.InputValidator;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
+
+@AndroidEntryPoint
 public class RefundDetailFragment extends Fragment {
 
     private EditText etRefundSaleId, etRefundReason;
@@ -27,6 +33,8 @@ public class RefundDetailFragment extends Fragment {
     private int saleId;
     private SaleFragment saleFragment;
 
+    @Inject SaleApi saleApi;
+
     public void setSaleFragment(SaleFragment fragment) {
         this.saleFragment = fragment;
     }

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

@@ -15,7 +15,6 @@ import android.widget.TextView;
 import android.widget.Toast;
 
 import com.example.petstoremobile.R;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.ServiceApi;
 import com.example.petstoremobile.dtos.ServiceDTO;
 import com.example.petstoremobile.fragments.ListFragment;
@@ -23,10 +22,14 @@ import com.example.petstoremobile.fragments.listfragments.ServiceFragment;
 import com.example.petstoremobile.utils.ActivityLogger;
 import com.example.petstoremobile.utils.InputValidator;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class ServiceDetailFragment extends Fragment {
 
     private TextView tvMode, tvServiceId;
@@ -36,6 +39,8 @@ public class ServiceDetailFragment extends Fragment {
     private boolean isEditing = false;
     private ServiceFragment serviceFragment;
 
+    @Inject ServiceApi serviceApi;
+
     //set the service fragment to the parent so we refer back to service view when save or delete is done
     public void setServiceFragment(ServiceFragment fragment) {
         this.serviceFragment = fragment;
@@ -79,8 +84,6 @@ public class ServiceDetailFragment extends Fragment {
         serviceDTO.setServiceDuration(duration);
         serviceDTO.setServicePrice(price);
 
-        ServiceApi serviceApi = RetrofitClient.getServiceApi(requireContext());
-
         //check if the service is being edited or added
         if (isEditing) {
             // Update existing service
@@ -135,7 +138,6 @@ public class ServiceDetailFragment extends Fragment {
                 .setTitle("Delete Service")
                 .setMessage("Are you sure you want to delete " + etServiceName.getText().toString() + "?")
                 .setPositiveButton("Delete", (dialog, which) -> {
-                    ServiceApi serviceApi = RetrofitClient.getServiceApi(requireContext());
                     serviceApi.deleteService((long) serviceId).enqueue(new Callback<Void>() {
                         @Override
                         public void onResponse(Call<Void> call, Response<Void> response) {
@@ -205,4 +207,4 @@ public class ServiceDetailFragment extends Fragment {
         btnDeleteService = view.findViewById(R.id.btnDeleteService);
         btnBack = view.findViewById(R.id.btnBack);
     }
-}
+}

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

@@ -15,7 +15,6 @@ import android.widget.TextView;
 import android.widget.Toast;
 
 import com.example.petstoremobile.R;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.SupplierApi;
 import com.example.petstoremobile.dtos.SupplierDTO;
 import com.example.petstoremobile.fragments.ListFragment;
@@ -23,10 +22,14 @@ import com.example.petstoremobile.fragments.listfragments.SupplierFragment;
 import com.example.petstoremobile.utils.ActivityLogger;
 import com.example.petstoremobile.utils.InputValidator;
 
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class SupplierDetailFragment extends Fragment {
 
     private TextView tvMode, tvSupId;
@@ -36,6 +39,8 @@ public class SupplierDetailFragment extends Fragment {
     private boolean isEditing = false;
     private SupplierFragment supplierFragment;
 
+    @Inject SupplierApi supplierApi;
+
     //set the supplier fragment to the parent so we refer back to supplier view when save or delete is done
     public void setSupplierFragment(SupplierFragment fragment) {
         this.supplierFragment = fragment;
@@ -82,8 +87,6 @@ public class SupplierDetailFragment extends Fragment {
         supplierDTO.setSupEmail(email);
         supplierDTO.setSupPhone(phone);
 
-        SupplierApi supplierApi = RetrofitClient.getSupplierApi(requireContext());
-
         //check if the supplier is being edited or added
         if (isEditing) {
             // Update existing supplier
@@ -138,7 +141,6 @@ public class SupplierDetailFragment extends Fragment {
                 .setTitle("Delete Supplier")
                 .setMessage("Are you sure you want to delete " + etSupCompany.getText().toString() + "?")
                 .setPositiveButton("Delete", (dialog, which) -> {
-                    SupplierApi supplierApi = RetrofitClient.getSupplierApi(requireContext());
                     supplierApi.deleteSupplier((long) supId).enqueue(new Callback<Void>() {
                         @Override
                         public void onResponse(Call<Void> call, Response<Void> response) {
@@ -215,4 +217,4 @@ public class SupplierDetailFragment extends Fragment {
         btnDeleteSupplier = view.findViewById(R.id.btnDeleteSupplier);
         btnBack = view.findViewById(R.id.btnBack);
     }
-}
+}

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

@@ -29,7 +29,6 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.example.petstoremobile.R;
 import com.example.petstoremobile.api.PetApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.fragments.ListFragment;
 import com.example.petstoremobile.fragments.listfragments.detailfragments.PetDetailFragment;
 
@@ -40,6 +39,10 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import okhttp3.MediaType;
 import okhttp3.MultipartBody;
 import okhttp3.RequestBody;
@@ -47,6 +50,7 @@ import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
+@AndroidEntryPoint
 public class PetProfileFragment extends Fragment {
 
     private TextView tvPetName, tvPetSpecies, tvPetBreed, tvPetAge, tvPetPrice;
@@ -56,6 +60,9 @@ public class PetProfileFragment extends Fragment {
     private int petId;
     private boolean hasImage = false;
 
+    @Inject PetApi petApi;
+    @Inject @Named("baseUrl") String baseUrl;
+
     // launchers for camera and gallery
     private ActivityResultLauncher<Intent> galleryLauncher;
     private ActivityResultLauncher<Uri> cameraLauncher;
@@ -201,7 +208,7 @@ public class PetProfileFragment extends Fragment {
 
     // Helper function to load pet image from backend
     private void loadPetImage(int petId) {
-        String imageUrl = RetrofitClient.BASE_URL + String.format(Locale.US, PetApi.PET_IMAGE_PATH, petId);
+        String imageUrl = baseUrl + String.format(Locale.US, PetApi.PET_IMAGE_PATH, petId);
 
         Glide.with(this)
                 .load(imageUrl)
@@ -236,7 +243,6 @@ public class PetProfileFragment extends Fragment {
             MultipartBody.Part body = MultipartBody.Part.createFormData("image", file.getName(), requestFile);
 
             // Call the backend to upload the image
-            PetApi petApi = RetrofitClient.getPetApi(requireContext());
             petApi.uploadPetImage((long) petId, body).enqueue(new Callback<Void>() {
                 @Override
                 public void onResponse(Call<Void> call, Response<Void> response) {
@@ -261,7 +267,6 @@ public class PetProfileFragment extends Fragment {
     }
 
     private void deletePetImage() {
-        PetApi petApi = RetrofitClient.getPetApi(requireContext());
         petApi.deletePetImage((long) petId).enqueue(new Callback<Void>() {
             @Override
             public void onResponse(Call<Void> call, Response<Void> response) {

android/app/src/main/java/com/example/petstoremobile/services/ChatNotificationService.java

@@ -8,7 +8,6 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import com.example.petstoremobile.api.ChatApi;
 import com.example.petstoremobile.api.CustomerApi;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.api.auth.TokenManager;
 import com.example.petstoremobile.dtos.ConversationDTO;
 import com.example.petstoremobile.dtos.CustomerDTO;
@@ -21,11 +20,17 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
 
 // Service to receive notifications when a new conversation is created
+@AndroidEntryPoint
 public class ChatNotificationService extends Service {
     private static final String TAG = "ChatNotificationService";
 
@@ -37,6 +42,11 @@ public class ChatNotificationService extends Service {
     private final Map<Long, String> customerIdToName = new HashMap<>();
     private Long currentUserId;
 
+    @Inject CustomerApi customerApi;
+    @Inject ChatApi chatApi;
+    @Inject TokenManager tokenManager;
+    @Inject @Named("baseUrl") String baseUrl;
+
     //When the service starts, connect to the websocket
     @Override
     public int onStartCommand(Intent intent, int flags, int startId) {
@@ -48,14 +58,11 @@ public class ChatNotificationService extends Service {
     // helper function to connect to the websocket
     private void connectWebSocket() {
         //get the token and role from the shared preferences
-        TokenManager tm = TokenManager.getInstance(this);
+        String token = tokenManager.getToken();
-        String token = tm.getToken();
+        String role = tokenManager.getRole();
-        String role = tm.getRole();
+        currentUserId = tokenManager.getUserId();
-        currentUserId = tm.getUserId();
 
         if (token != null && stompChatManager == null) {
-            //load customers to have names associated with customer ids
-            CustomerApi customerApi = RetrofitClient.getCustomerApi(this);
             customerApi.getAllCustomers(0, 1000).enqueue(new Callback<PageResponse<CustomerDTO>>() {
                 @Override
                 public void onResponse(@NonNull Call<PageResponse<CustomerDTO>> call, @NonNull Response<PageResponse<CustomerDTO>> response) {
@@ -78,7 +85,6 @@ public class ChatNotificationService extends Service {
 
     private void loadConversationsAndStartStomp(String token, String role) {
         // Fetch existing conversations
-        ChatApi chatApi = RetrofitClient.getChatApi(this);
         chatApi.getAllConversations().enqueue(new Callback<List<ConversationDTO>>() {
             @Override
             public void onResponse(@NonNull Call<List<ConversationDTO>> call, @NonNull Response<List<ConversationDTO>> response) {
@@ -110,7 +116,7 @@ public class ChatNotificationService extends Service {
     private void startStomp(String token, String role) {
         if (stompChatManager != null) return;
 
-        stompChatManager = new StompChatManager(token, role);
+        stompChatManager = new StompChatManager(token, role, baseUrl);
 
         // Listen for messages in existing conversations
         stompChatManager.setMessageListener(message -> {
@@ -193,7 +199,6 @@ public class ChatNotificationService extends Service {
 
     // Helper function to fetch customer name for a conversation
     private void fetchCustomerName(Long customerId) {
-        CustomerApi customerApi = RetrofitClient.getCustomerApi(this);
         customerApi.getCustomerById(customerId).enqueue(new Callback<CustomerDTO>() {
             @Override
             public void onResponse(@NonNull Call<CustomerDTO> call, @NonNull Response<CustomerDTO> response) {
@@ -223,4 +228,4 @@ public class ChatNotificationService extends Service {
     public IBinder onBind(Intent intent) {
         return null;
     }
-}
+}

android/app/src/main/java/com/example/petstoremobile/websocket/StompChatManager.java

@@ -3,7 +3,6 @@ package com.example.petstoremobile.websocket;
 import android.os.Handler;
 import android.os.Looper;
 import android.util.Log;
-import com.example.petstoremobile.api.RetrofitClient;
 import com.example.petstoremobile.dtos.ConversationDTO;
 import com.example.petstoremobile.dtos.MessageDTO;
 import com.google.gson.Gson;
@@ -54,14 +53,16 @@ public class StompChatManager {
     private ConnectionListener connectionListener;
     private final String authToken;
     private final String role;
+    private final String baseUrl;
     private boolean isConnected;
     private boolean isConnecting;
     private boolean manualDisconnect;
     private Long pendingConversationId;
 
-    public StompChatManager(String authToken, String role) {
+    public StompChatManager(String authToken, String role, String baseUrl) {
         this.authToken = authToken;
         this.role = role == null ? "" : role.trim().toUpperCase(Locale.ROOT);
+        this.baseUrl = baseUrl;
     }
 
     public void setMessageListener(MessageListener listener) {
@@ -267,16 +268,16 @@ public class StompChatManager {
 
     // Make the URL for the websocket connection
     private String buildWebSocketUrl() {
-        String baseUrl = RetrofitClient.BASE_URL.endsWith("/")
+        String cleanBaseUrl = baseUrl.endsWith("/")
-                ? RetrofitClient.BASE_URL.substring(0, RetrofitClient.BASE_URL.length() - 1)
+                ? baseUrl.substring(0, baseUrl.length() - 1)
-                : RetrofitClient.BASE_URL;
+                : baseUrl;
-        if (baseUrl.startsWith("https://")) {
+        if (cleanBaseUrl.startsWith("https://")) {
-            return "wss://" + baseUrl.substring("https://".length()) + "/ws/chat";
+            return "wss://" + cleanBaseUrl.substring("https://".length()) + "/ws/chat";
         }
-        if (baseUrl.startsWith("http://")) {
+        if (cleanBaseUrl.startsWith("http://")) {
-            return "ws://" + baseUrl.substring("http://".length()) + "/ws/chat";
+            return "ws://" + cleanBaseUrl.substring("http://".length()) + "/ws/chat";
         }
-        return baseUrl + "/ws/chat";
+        return cleanBaseUrl + "/ws/chat";
     }
 
     // Helper to check if the current user is a customer
@@ -292,4 +293,4 @@ public class StompChatManager {
         reconnectHandler.removeCallbacksAndMessages(null);
         reconnectHandler.postDelayed(this::connect, 1000);
     }
-}
+}

android/build.gradle.kts

@@ -1,4 +1,5 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
     alias(libs.plugins.android.application) apply false
+    alias(libs.plugins.hilt) apply false
 }

android/gradle/libs.versions.toml

@@ -8,6 +8,7 @@ material = "1.13.0"
 activity = "1.12.4"
 constraintlayout = "2.2.1"
 swiperefreshlayout = "1.2.0"
+hilt = "2.51.1"
 
 [libraries]
 junit = { group = "junit", name = "junit", version.ref = "junit" }
@@ -18,7 +19,9 @@ material = { group = "com.google.android.material", name = "material", version.r
 activity = { group = "androidx.activity", name = "activity", version.ref = "activity" }
 constraintlayout = { group = "androidx.constraintlayout", name = "constraintlayout", version.ref = "constraintlayout" }
 swiperefreshlayout = { group = "androidx.swiperefreshlayout", name = "swiperefreshlayout", version.ref = "swiperefreshlayout" }
+hilt-android = { group = "com.google.dagger", name = "hilt-android", version.ref = "hilt" }
+hilt-compiler = { group = "com.google.dagger", name = "hilt-compiler", version.ref = "hilt" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
-
+hilt = { id = "com.google.dagger.hilt.android", version.ref = "hilt" }