Added dummy countdown timer to midnight to the toolbar

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

@@ -16,7 +16,30 @@
             android:layout_width="match_parent"
             android:layout_height="?attr/actionBarSize"
             android:background="?attr/colorPrimary"
-            app:popupTheme="@style/AppTheme.PopupOverlay" />
+            app:popupTheme="@style/AppTheme.PopupOverlay">
+
+            <androidx.constraintlayout.widget.ConstraintLayout
+                android:id="@+id/timer_layout"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent">
+
+                <TextView
+                    android:id="@+id/time_to_aos"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginEnd="16dp"
+                    android:gravity="center"
+                    android:text="@string/next_aos_pattern"
+                    android:textSize="24sp"
+                    app:layout_constraintBottom_toBottomOf="parent"
+                    app:layout_constraintEnd_toEndOf="parent"
+                    app:layout_constraintHorizontal_bias="0.5"
+                    app:layout_constraintStart_toStartOf="parent"
+                    app:layout_constraintTop_toTopOf="parent" />
+
+            </androidx.constraintlayout.widget.ConstraintLayout>
+
+        </androidx.appcompat.widget.Toolbar>
 
     </com.google.android.material.appbar.AppBarLayout>
 

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

@@ -22,5 +22,6 @@
     <string name="height_def">64</string>
     <string name="height_summary">Ground station height in meters AMSL</string>
 
+    <string name="next_aos_pattern">Next AOS in %02d:%02d:%02d</string>
     <string name="placeholder">Placeholder</string>
 </resources>