tone down placeholders in dark mode

Resolves #1140

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

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

@@ -32,7 +32,8 @@
         android:layout_centerVertical="true"
         android:layout_marginEnd="@dimen/double_margin_between_elements"
         android:contentDescription="@null"
-        app:corners="100" />
+        app:corners="100"
+        app:custom_color="@color/nc_shimmer_default_color" />
 
     <LinearLayout
         android:layout_width="match_parent"
@@ -45,12 +46,14 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginEnd="128dp"
-            android:textStyle="bold" />
+            android:textStyle="bold"
+            app:custom_color="@color/nc_shimmer_default_color" />
 
         <com.elyeproj.loaderviewlibrary.LoaderTextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:layout_marginTop="6dp" />
+            android:layout_marginTop="6dp"
+            app:custom_color="@color/nc_shimmer_darker_color" />
 
     </LinearLayout>
 

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

@@ -28,13 +28,15 @@
         android:layout_height="@dimen/iconized_single_line_item_icon_size"
         android:layout_gravity="center_vertical"
         android:layout_marginStart="@dimen/standard_margin"
-        app:corners="100" />
+        app:corners="100"
+        app:custom_color="@color/nc_shimmer_default_color" />
 
     <com.elyeproj.loaderviewlibrary.LoaderTextView
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_gravity="center_vertical"
         android:layout_marginStart="@dimen/standard_margin"
-        android:layout_marginEnd="@dimen/standard_margin" />
+        android:layout_marginEnd="@dimen/standard_margin"
+        app:custom_color="@color/nc_shimmer_default_color" />
 
 </LinearLayout>

app/src/main/res/values-night/colors.xml

@@ -58,4 +58,8 @@
     <color name="bg_message_list_incoming_bubble_deleted">#66484848</color>
 
     <color name="textColorMaxContrast">#8c8c8c</color>
+
+    <!-- shimmer element colors -->
+    <color name="nc_shimmer_default_color">#4B4B4B</color>
+    <color name="nc_shimmer_darker_color">#282828</color>
 </resources>

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

@@ -76,4 +76,8 @@
 
     <color name="call_buttons_background">#BF999999</color>
     <color name="favorite_icon_tint">#FFCC00</color>
+
+    <!-- shimmer element colors -->
+    <color name="nc_shimmer_default_color">#D7D7D7</color>
+    <color name="nc_shimmer_darker_color">#B4B4B4</color>
 </resources>