Fix preference header background

app/src/main/res/drawable/preference_header_background_black.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright 2018 Hippo Seven
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:state_activated="true" android:drawable="@drawable/grey_900"/>
+    <item android:drawable="@drawable/transparent"/>
+
+</selector>

app/src/main/res/drawable/preference_header_background_dark.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright 2018 Hippo Seven
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:state_activated="true" android:drawable="@drawable/grey_800"/>
+    <item android:drawable="@drawable/transparent"/>
+
+</selector>

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

@@ -22,7 +22,7 @@
     android:gravity="center_vertical"
     android:minHeight="72dp"
     android:orientation="horizontal"
-    android:background="@drawable/preference_header_background">
+    android:background="?attr/preferenceHeaderBackground">
 
     <ImageView
         android:id="@android:id/icon"

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

@@ -63,6 +63,8 @@
 
         <attr name="gallerySliderBackgroundColor" format="color"/>
 
+        <attr name="preferenceHeaderBackground" format="reference"/>
+
         <attr name="toolbarPopupTheme" format="reference"/>
         <attr name="galleryDetailDivider" format="reference"/>
     </declare-styleable>

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

@@ -17,6 +17,8 @@
 <resources>
 
     <drawable name="grey_200">@color/grey_200</drawable>
+    <drawable name="grey_800">@color/grey_800</drawable>
+    <drawable name="grey_900">@color/grey_900</drawable>
     <drawable name="transparent">@android:color/transparent</drawable>
     <drawable name="tile_background_activated">#7f9c27b0</drawable>
 

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

@@ -50,6 +50,7 @@
         <item name="galleryDetailHeaderBackgroundColor">?attr/contentColorThemePrimary</item>
         <item name="galleryDetailButtonBackgroundColor">@color/gallery_detail_button_background_light</item>
 
+        <item name="preferenceHeaderBackground">@drawable/preference_header_background_light</item>
         <item name="toolbarPopupTheme">@style/ThemeOverlay.AppCompat.Light</item>
         <item name="galleryDetailDivider">@drawable/divider_gallery_detail_light</item>
     </style>
@@ -102,6 +103,7 @@
         <item name="galleryDetailHeaderBackgroundColor">?attr/contentColorThemePrimary</item>
         <item name="galleryDetailButtonBackgroundColor">@color/gallery_detail_button_background_dark</item>
 
+        <item name="preferenceHeaderBackground">@drawable/preference_header_background_dark</item>
         <item name="toolbarPopupTheme">@style/ThemeOverlay.AppCompat.Dark</item>
         <item name="galleryDetailDivider">@drawable/divider_gallery_detail_dark</item>
     </style>
@@ -156,6 +158,7 @@
         <item name="galleryDetailHeaderBackgroundColor">@android:color/black</item>
         <item name="galleryDetailButtonBackgroundColor">@color/gallery_detail_button_background_black</item>
 
+        <item name="preferenceHeaderBackground">@drawable/preference_header_background_black</item>
         <item name="toolbarPopupTheme">@style/ThemeOverlay.AppCompat.Dark</item>
         <item name="galleryDetailDivider">@drawable/divider_gallery_detail_dark</item>
     </style>