Merge pull request 'Checkerboard background for transparency in zoomed images' (#92) from davidoskky/ReaderForSelfoss-multiplatform:checkerboard into master

Reviewed-on: https://gitea.amine-louveau.fr/Louvorg/ReaderForSelfoss-multiplatform/pulls/92

androidApp/src/main/res/drawable/checkerboard.xml

@@ -0,0 +1,5 @@
+<bitmap
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:dither="true"
+    android:src="@drawable/checktile"
+    android:tileMode="repeat"/>

androidApp/src/main/res/layout/fragment_image.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
@@ -9,8 +9,8 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:layout_centerVertical="true"
-        android:layout_centerHorizontal="true"
+        android:adjustViewBounds="true"
-        android:background="@android:color/black"
+        android:background="@drawable/checkerboard"
         app:srcCompat="@android:drawable/screen_background_dark" />
 
-</androidx.coordinatorlayout.widget.CoordinatorLayout>
+</RelativeLayout>