feat: Add edit button for existing categories

app/src/main/java/com/p_vacho/neat_calendar/activities/CategoriesActivity.kt

@@ -18,7 +18,6 @@ import com.p_vacho.neat_calendar.R
 import com.p_vacho.neat_calendar.adapters.CategoryAdapter
 import com.p_vacho.neat_calendar.api.RetrofitClient
 import com.p_vacho.neat_calendar.api.models.CategoryResponse
-import com.p_vacho.neat_calendar.api.models.EventResponse
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -38,7 +37,12 @@ class CategoriesActivity : AppCompatActivity() {
             @Suppress("DEPRECATION")
             val newCategory: CategoryResponse? = result.data?.getParcelableExtra("newCategory")
 
-            newCategory?.let { categoryCreateReply(it) }
+            @Suppress("DEPRECATION")
+            val editedCategory: CategoryResponse? = result.data?.getParcelableExtra("editedCategory")
+
+            if (newCategory != null && editedCategory != null) throw IllegalStateException("Got both edit & new response")
+            if (newCategory != null) categoryCreateReply(newCategory, CategoryMode.CREATE)
+            if (editedCategory != null) categoryCreateReply(editedCategory, CategoryMode.EDIT)
         }
     }
 
@@ -59,14 +63,14 @@ class CategoriesActivity : AppCompatActivity() {
         tvEmptyState = findViewById(R.id.tvEmptyState)
 
         btnBack.setOnClickListener { finish() }
-        btnAddCategory.setOnClickListener { navigateToCreateCategory() }
+        btnAddCategory.setOnClickListener { handleCreateCategory() }
 
         rvCategories.layoutManager = LinearLayoutManager(this)
 
         lifecycleScope.launch {
             categories = fetchCategories().toMutableList()
 
-            val adapter = CategoryAdapter(categories, ::handleDeleteCategory)
+            val adapter = CategoryAdapter(categories, ::handleDeleteCategory, ::handleEditCategory)
 
             rvCategories.adapter = adapter
             updateEmptyState()
@@ -105,20 +109,44 @@ class CategoriesActivity : AppCompatActivity() {
     }
 
     /**
-     * Navigates to the activity for adding a new category.
+     * Handle create category button getting pressed.
+     *
+     * Navigates to the create category activity in create mode.
      */
-    private fun navigateToCreateCategory() {
-        val intent = Intent(this, CreateCategoryActivity::class.java)
-        startActivity(intent)
+    private fun handleCreateCategory() {
+        val intent = Intent(this, CreateCategoryActivity::class.java).apply {
+            putExtra("mode", CategoryMode.CREATE.name)
+        }
+        createActivityLauncher.launch(intent)
+    }
+
+    /**
+     * Handle edit category button being pressed.
+     *
+     * Navigates to the create category activity in edit mode.
+     */
+    private fun handleEditCategory(category: CategoryResponse, position: Int) {
+        val intent = Intent(this, CreateCategoryActivity::class.java).apply {
+            putExtra("mode", CategoryMode.EDIT.name)
+            putExtra("category", category)
+        }
+        createActivityLauncher.launch(intent)
     }
 
     /**
      * Used as a callback, triggered when the CreateCategory Activity returns a result.
      *
-     * The returned value (the new category data) is passed over as a parameter.
+     * The returned value (the new / edited category data) is passed over as a parameter.
      */
-    private fun categoryCreateReply(category: CategoryResponse) {
-        (rvCategories.adapter as CategoryAdapter).addCategory(category)
+    private fun categoryCreateReply(category: CategoryResponse, mode: CategoryMode) {
+        val adapter = (rvCategories.adapter as CategoryAdapter)
+        when (mode) {
+            CategoryMode.CREATE -> {
+                adapter.addCategory(category)
+                updateEmptyState()
+            }
+            CategoryMode.EDIT -> { adapter.editCategory(category) }
+        }
     }
 
     /**

app/src/main/java/com/p_vacho/neat_calendar/activities/CreateCategoryActivity.kt

@@ -7,6 +7,10 @@ import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
 import com.p_vacho.neat_calendar.R
 
+enum class CategoryMode {
+    CREATE, EDIT
+}
+
 class CreateCategoryActivity : AppCompatActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)

app/src/main/java/com/p_vacho/neat_calendar/adapters/CategoryAdapter.kt

@@ -11,12 +11,14 @@ import com.p_vacho.neat_calendar.api.models.CategoryResponse
 
 class CategoryAdapter(
     private val categories: MutableList<CategoryResponse>,
-    private val onDeleteClick: (CategoryResponse, Int) -> Unit
+    private val onDeleteClick: (CategoryResponse, Int) -> Unit,
+    private val onEditClick: (CategoryResponse, Int) -> Unit
 ) : RecyclerView.Adapter<CategoryAdapter.CategoryViewHolder>() {
 
     inner class CategoryViewHolder(view: View) : RecyclerView.ViewHolder(view) {
         val colorIndicator: View = view.findViewById(R.id.colorIndicator)
         val categoryName: TextView = view.findViewById(R.id.tvCategoryName)
+        val editButton: ImageButton = view.findViewById(R.id.btnEditCategory)
         val deleteButton: ImageButton = view.findViewById(R.id.btnDeleteCategory)
     }
 
@@ -33,10 +35,9 @@ class CategoryAdapter(
         holder.colorIndicator.setBackgroundColor(category.color.toArgb())
         holder.categoryName.text = category.name
 
-        // Set click listener for the delete button
-        holder.deleteButton.setOnClickListener {
-            onDeleteClick(category, position)
-        }
+        // Set click listeners for the buttons
+        holder.deleteButton.setOnClickListener { onDeleteClick(category, position) }
+        holder.editButton.setOnClickListener { onEditClick(category, position) }
     }
 
     override fun getItemCount(): Int = categories.size
@@ -64,4 +65,15 @@ class CategoryAdapter(
         categories.add(category)
         notifyItemInserted(categories.size)
     }
+
+    /**
+     * Edit an existing category, updating it in the UI.
+     *
+     * Call this after the onEditClick callback edits the category from the backend API.
+     */
+    fun editCategory(category: CategoryResponse) {
+        val position = categories.indexOfFirst { it.id == category.id }
+        categories[position] = category
+        notifyItemChanged(position)
+    }
 }

app/src/main/res/layout/item_category.xml

@@ -40,7 +40,28 @@
             app:layout_constraintTop_toTopOf="parent"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintStart_toEndOf="@id/colorIndicator"
-            app:layout_constraintEnd_toStartOf="@id/btnDeleteCategory" />
+            app:layout_constraintEnd_toStartOf="@id/buttonContainer" />
+
+        <!-- Button Container -->
+        <LinearLayout
+            android:id="@+id/buttonContainer"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent">
+
+            <!-- Edit Button -->
+            <ImageButton
+                android:id="@+id/btnEditCategory"
+                android:layout_width="40dp"
+                android:layout_height="40dp"
+                android:background="?attr/selectableItemBackgroundBorderless"
+                android:src="@drawable/ic_pencil"
+                android:contentDescription="@string/edit_category"
+                app:tint="?android:attr/textColorSecondary" />
 
             <!-- Delete Button -->
             <ImageButton
@@ -50,10 +71,8 @@
                 android:background="?attr/selectableItemBackgroundBorderless"
                 android:src="@drawable/ic_trashbin"
                 android:contentDescription="@string/delete_category"
-            app:tint="?android:attr/textColorSecondary"
-            app:layout_constraintTop_toTopOf="parent"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toEndOf="parent" />
+                app:tint="?android:attr/textColorSecondary" />
+        </LinearLayout>
 
     </androidx.constraintlayout.widget.ConstraintLayout>
 </androidx.cardview.widget.CardView>

app/src/main/res/values/strings.xml

@@ -96,4 +96,5 @@
     <string name="no_categories_placeholder">This event has no categories.</string>
     <string name="event_owner_section">Event owner:</string>
     <string name="no_invited_categories_placeholder">You can\'t see categories for invited events</string>
+    <string name="edit_category">Edit category</string>
 </resources>