diff --git a/component/viewer/src/main/res/layout/fragment_component_viewer_top.xml b/component/viewer/src/main/res/layout/fragment_component_viewer_top.xml
index 678d0418..6c8791de 100644
--- a/component/viewer/src/main/res/layout/fragment_component_viewer_top.xml
+++ b/component/viewer/src/main/res/layout/fragment_component_viewer_top.xml
@@ -37,6 +37,16 @@
 
             </com.google.android.material.appbar.CollapsingToolbarLayout>
 
+
+            <ProgressBar
+                android:id="@+id/loading_progress_bar"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:layout_gravity="center"
+                android:indeterminate="true"
+                android:background="@color/colorSurface"
+                android:visibility="gone" />
+
         </com.google.android.material.appbar.AppBarLayout>
 
         <androidx.recyclerview.widget.RecyclerView
diff --git a/utils/src/main/java/one/nem/lacerta/utils/FeatureSwitch.java b/utils/src/main/java/one/nem/lacerta/utils/FeatureSwitch.java
index 11cebefc..14832a5c 100644
--- a/utils/src/main/java/one/nem/lacerta/utils/FeatureSwitch.java
+++ b/utils/src/main/java/one/nem/lacerta/utils/FeatureSwitch.java
@@ -10,6 +10,12 @@ public class FeatureSwitch {
         public static boolean useSimpleNotifyMethod = true;
     }
 
+    public static class Viewer {
+        public static boolean showOriginalImage = false;
+        public static int maxImageSize = 1024;
+        public static boolean showProgressBarWhenLoading = true;
+    }
+
     public static class FeatureMaster {
         public static boolean enableSearch = false;
         public static boolean enableDebugMenu = true;