Merge "Make topology hint readable when block is under it" into main

res/layout/display_topology_preference.xml

@@ -31,11 +31,26 @@
         android:id="@+id/display_topology_pane_content"
         android:layout_width="match_parent"
         android:layout_height="match_parent"/>
-    <TextView
-        android:id="@+id/topology_hint"
+
+    <!-- Give the textview a solid-color background (the same as the pane) in
+         order to make the text clear when a DisplayBlock is drawn under it as
+         part of display_topology_pane_content.
+
+         If the padding is in the TextView, then the background will fill the
+         padding, which we don't want vertically, as there is a lot of vertical
+         padding. We do need some horizontal padding because otherwise the
+         rounded corners will touch the edge of the text. -->
+    <FrameLayout
+        android:importantForAccessibility="no"
         android:layout_height="wrap_content"
         android:layout_width="wrap_content"
         android:layout_gravity="top|center_horizontal"
-        android:paddingBottom="10dp"
-        android:paddingTop="10dp" />
+        android:paddingVertical="10dp">
+        <TextView
+            android:id="@+id/topology_hint"
+            android:background="@drawable/display_topology_background"
+            android:paddingHorizontal="5dp"
+            android:layout_height="wrap_content"
+            android:layout_width="wrap_content" />
+    </FrameLayout>
 </FrameLayout>