feat: Add (blank) categories activity & logic to enter it

app/src/main/AndroidManifest.xml

@@ -16,6 +16,9 @@
         android:supportsRtl="true"
         android:theme="@style/Theme.NeatCalendar"
         tools:targetApi="31">
+        <activity
+            android:name=".activities.CategoriesActivity"
+            android:exported="false" />
         <activity
             android:name=".activities.NotificationsActivity"
             android:exported="false" />

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

@@ -0,0 +1,21 @@
+package com.p_vacho.neat_calendar.activities
+
+import android.os.Bundle
+import androidx.activity.enableEdgeToEdge
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.view.ViewCompat
+import androidx.core.view.WindowInsetsCompat
+import com.p_vacho.neat_calendar.R
+
+class CategoriesActivity : AppCompatActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        enableEdgeToEdge()
+        setContentView(R.layout.activity_categories)
+        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
+            val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
+            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
+            insets
+        }
+    }
+}

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

@@ -265,6 +265,10 @@ class CreateEventActivity : AppCompatActivity() {
             .setNegativeButton(getString(R.string.cancel)) { dialog, _ ->
                 dialog.dismiss()
             }
+            .setNeutralButton(getString(R.string.manage_categories)) { dialog, _ ->
+                navigateToCategoriesActivity()
+                dialog.dismiss()
+            }
 
         builder.create().show()
     }
@@ -418,4 +422,19 @@ class CreateEventActivity : AppCompatActivity() {
             categoryViewSwitcher.displayedChild = 0 // Show RecyclerView
         }
     }
+
+    /**
+     * Navigate to the Categories Activity, without closing this activity,
+     * hence allowing the user to return back.
+     */
+    private fun navigateToCategoriesActivity() {
+        val intent = Intent(this, CategoriesActivity::class.java)
+        startActivity(intent)
+    }
+
+    override fun onResume() {
+        super.onResume()
+        // Re-fetch categories when returning (most likely from CategoriesActivity)
+        fetchCategories()
+    }
 }

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

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.CategoriesActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>

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

@@ -74,4 +74,5 @@
     <string name="event_saved">Event Saved: %1$s</string>
     <string name="choose_event_color">Choose Event Color</string>
     <string name="select_time">Select Time</string>
+    <string name="manage_categories">Manage categories</string>
 </resources>