Added database persistence ability

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

@@ -4,7 +4,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".fragment.FirstFragment">
+    tools:context=".fragment.EventFragment">
 
         <androidx.recyclerview.widget.RecyclerView
             android:id="@+id/recycler_view"

app/src/main/res/navigation/nav_graph.xml

@@ -7,9 +7,9 @@
 
     <fragment
         android:id="@+id/FirstFragment"
-        android:name="com.denizk0461.studip.fragment.FirstFragment"
+        android:name="com.denizk0461.studip.fragment.EventFragment"
         android:label="@string/first_fragment_label"
-        tools:layout="@layout/fragment_first">
+        tools:layout="@layout/fragment_event">
 
         <action
             android:id="@+id/action_FirstFragment_to_SecondFragment"