diff --git a/services/core/java/com/android/server/UiModeManagerService.java b/services/core/java/com/android/server/UiModeManagerService.java
index b994e6c58e641..f2d5a9b685f44 100644
--- a/services/core/java/com/android/server/UiModeManagerService.java
+++ b/services/core/java/com/android/server/UiModeManagerService.java
@@ -302,15 +302,19 @@ final class UiModeManagerService extends SystemService {
     private final ContentObserver mDarkThemeObserver = new ContentObserver(mHandler) {
         @Override
         public void onChange(boolean selfChange, Uri uri) {
-            int mode = Secure.getIntForUser(getContext().getContentResolver(), Secure.UI_NIGHT_MODE,
-                    mNightMode, 0);
-            if (mode == MODE_NIGHT_AUTO || mode == MODE_NIGHT_CUSTOM) {
-                mode = MODE_NIGHT_YES;
-            }
-            SystemProperties.set(SYSTEM_PROPERTY_DEVICE_THEME, Integer.toString(mode));
+            updateSystemProperties();
         }
     };
 
+    private void updateSystemProperties() {
+        int mode = Secure.getIntForUser(getContext().getContentResolver(), Secure.UI_NIGHT_MODE,
+                mNightMode, 0);
+        if (mode == MODE_NIGHT_AUTO || mode == MODE_NIGHT_CUSTOM) {
+            mode = MODE_NIGHT_YES;
+        }
+        SystemProperties.set(SYSTEM_PROPERTY_DEVICE_THEME, Integer.toString(mode));
+    }
+
     @Override
     public void onSwitchUser(int userHandle) {
         super.onSwitchUser(userHandle);
@@ -392,6 +396,7 @@ final class UiModeManagerService extends SystemService {
 
         context.getContentResolver().registerContentObserver(Secure.getUriFor(Secure.UI_NIGHT_MODE),
                 false, mDarkThemeObserver, 0);
+        updateSystemProperties();
     }
 
     @VisibleForTesting