feat(createEvent): Add ui for category adding

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

@@ -9,20 +9,26 @@ import android.os.Bundle
 import android.util.Log
 import android.view.View
 import android.widget.EditText
+import android.widget.ImageButton
 import android.widget.Toast
+import android.widget.ViewSwitcher
 import androidx.activity.enableEdgeToEdge
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
 import androidx.lifecycle.lifecycleScope
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
 import com.github.dhaval2404.colorpicker.ColorPickerDialog
 import com.google.android.material.button.MaterialButton
 import com.google.android.material.button.MaterialButtonToggleGroup
 import com.google.android.material.textfield.TextInputEditText
 import com.google.gson.Gson
 import com.p_vacho.neat_calendar.R
+import com.p_vacho.neat_calendar.adapters.CategoryChipAdapter
 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.EventRequest
 import com.p_vacho.neat_calendar.api.models.EventResponse
 import com.p_vacho.neat_calendar.api.models.ValidationError
@@ -45,7 +51,12 @@ class CreateEventActivity : AppCompatActivity() {
     private lateinit var txtEndTime: TextInputEditText
     private lateinit var btnCreateEvent: MaterialButton
     private lateinit var btnColorPicker: MaterialButton
+    private lateinit var addCategoryButton: ImageButton
+    private lateinit var categoryRecyclerView: RecyclerView
+    private lateinit var categoryViewSwitcher: ViewSwitcher
 
+    private lateinit var eventCategories: MutableList<CategoryResponse>
+    private lateinit var allCategories: List<CategoryResponse>
     private lateinit var defaultDate: LocalDate
 
     private var instantEvent: Boolean = true
@@ -66,8 +77,13 @@ class CreateEventActivity : AppCompatActivity() {
         val dateString = intent.getStringExtra("date")!!
         defaultDate = LocalDate.parse(dateString)
 
+        // TODO: Fetch the available categories from the API
+        allCategories = emptyList()
+        eventCategories = mutableListOf()
+
         initializeViews()
         setupListeners()
+        updateCategoryView()
     }
 
     private fun initializeViews() {
@@ -80,6 +96,13 @@ class CreateEventActivity : AppCompatActivity() {
         txtEndTime = findViewById(R.id.txtEndTime)
         btnCreateEvent = findViewById(R.id.btnCreateEvent)
         btnColorPicker = findViewById(R.id.btnColorPicker)
+        addCategoryButton = findViewById(R.id.btnAddCategory)
+        categoryViewSwitcher = findViewById(R.id.categoryViewSwitcher)
+        categoryRecyclerView = findViewById(R.id.categoryChipRecyclerView)
+
+        categoryRecyclerView.layoutManager =
+            LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
+        categoryRecyclerView.adapter = CategoryChipAdapter(eventCategories, true, ::onCategoryRemoved)
 
         selectedColor = ContextCompat.getColor(this, R.color.event_indicator_color)
     }
@@ -122,10 +145,33 @@ class CreateEventActivity : AppCompatActivity() {
             }
         }
 
+        addCategoryButton.setOnClickListener { addCategory() }
         btnColorPicker.setOnClickListener { openColorPickerDialog() }
         btnCreateEvent.setOnClickListener { createEvent() }
     }
 
+    private fun addCategory() {
+        // This should probably open some modal with a dropdown
+        // showing all the available categories (without the already picked ones)
+
+        var newCategory = TODO("Implement category adding")
+        if (newCategory == null) return
+
+        eventCategories.add(newCategory)
+        categoryRecyclerView.adapter!!.notifyItemInserted(eventCategories.size - 1)
+        updateCategoryView()
+    }
+
+    /**
+     * This is triggered by the CategoryChipAdapter, when the remove button on
+     * the category chip was clicked.
+     */
+    private fun onCategoryRemoved(category: CategoryResponse, position: Int) {
+        TODO("Implement category removing")
+
+        updateCategoryView()
+    }
+
     private fun createEvent() {
         val title = etEventTitle.text.toString()
         val description = etEventDescription.text.toString()
@@ -222,4 +268,12 @@ class CreateEventActivity : AppCompatActivity() {
     private fun formatDateTime(dateTime: LocalDateTime?): String {
         return dateTime?.format(java.time.format.DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm")) ?: "Select Time"
     }
+
+    private fun updateCategoryView() {
+        if (eventCategories.isEmpty()) {
+            categoryViewSwitcher.displayedChild = 1 // Show placeholder text
+        } else {
+            categoryViewSwitcher.displayedChild = 0 // Show RecyclerView
+        }
+    }
 }

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

@@ -13,7 +13,7 @@ import com.p_vacho.neat_calendar.api.models.CategoryResponse
 class CategoryChipAdapter(
     private val categories: List<CategoryResponse>,
     private val isRemovable: Boolean = false,
-    private val onRemoveCategory: ((CategoryResponse) -> Unit)? = null
+    private val onRemoveCategory: ((CategoryResponse, Int) -> Unit)? = null
 ) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
 
     inner class CategoryViewHolder(val textView: TextView) : RecyclerView.ViewHolder(textView)
@@ -50,7 +50,7 @@ class CategoryChipAdapter(
             holder.textView.backgroundTintList = ColorStateList.valueOf(category.color.toArgb())
 
             holder.removeButton.setOnClickListener {
-                onRemoveCategory?.invoke(category)
+                onRemoveCategory?.invoke(category, position)
             }
         }
     }

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

@@ -1,6 +1,5 @@
 package com.p_vacho.neat_calendar.adapters
 
-import android.graphics.Color
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup

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

@@ -128,6 +128,55 @@
             app:cornerRadius="8dp"
             style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
 
+        <!-- Categories Section -->
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="16dp"
+            android:orientation="horizontal"
+            android:gravity="center_vertical">
+
+            <ViewSwitcher
+                android:id="@+id/categoryViewSwitcher"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:animateFirstView="true">
+
+                <!-- RecyclerView for categories -->
+                <androidx.recyclerview.widget.RecyclerView
+                    android:id="@+id/categoryChipRecyclerView"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    tools:listitem="@layout/item_removable_category_chip"
+                    tools:itemCount="3"
+                    tools:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
+                    tools:orientation="horizontal" />
+
+                <!-- Placeholder Text, when there aren't any categories -->
+                <TextView
+                    android:id="@+id/txtPlaceholder"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:gravity="center"
+                    android:padding="8dp"
+                    android:text="@string/add_category"
+                    android:textAppearance="?attr/textAppearanceBody1"
+                    android:textColor="?attr/colorOnSurface" />
+            </ViewSwitcher>
+
+            <!-- Add Button -->
+            <ImageButton
+                android:id="@+id/btnAddCategory"
+                android:layout_width="40dp"
+                android:layout_height="40dp"
+                android:background="?attr/selectableItemBackgroundBorderless"
+                android:src="@drawable/ic_add"
+                app:tint="?attr/colorPrimary"
+                android:contentDescription="@string/add_category" />
+
+        </LinearLayout>
+
         <!-- Create Button -->
         <com.google.android.material.button.MaterialButton
             android:id="@+id/btnCreateEvent"

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

@@ -42,4 +42,5 @@
     <string name="create_event">Create Event</string>
     <string name="select_color">Select Color</string>
     <string name="remove_category">Remove the category</string>
+    <string name="add_category">Add category</string>
 </resources>