encrypted export WIP

OpenKeychain/src/main/res/layout/backup_code_fragment.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:orientation="vertical"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="center"
+    android:paddingTop="10dp">
+
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:padding="10dp"
+        android:layout_gravity="center_horizontal"
+        android:text="Your key backup will be encrypted with this code:"
+        />
+
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:padding="10dp"
+        android:layout_margin="20dp"
+        android:id="@+id/backup_code"
+        tools:text="abcde-fghij-klmno-pqrst"
+        style="?android:textAppearanceLarge"
+        />
+
+    <Button
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_margin="10dp"
+        android:text="Ok, I wrote it down!"
+        android:id="@+id/button_ok"
+        style="?buttonStyle"
+        />
+
+</LinearLayout>