ui: adapt the share fragment for landscape

In landscape mode, the "infos" textView is layed out to the left of the
QR code.
Also fix the case where the shareURI is empty.

Change-Id: I4999bd80bc8bd791f9296f8fffc76b58459e47a1
Tuleap: #1430
diff --git a/ring-android/app/src/main/res/layout/frag_share.xml b/ring-android/app/src/main/res/layout/frag_share.xml
index 6680f6b..1d246d4 100644
--- a/ring-android/app/src/main/res/layout/frag_share.xml
+++ b/ring-android/app/src/main/res/layout/frag_share.xml
@@ -3,37 +3,6 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
-    <TextView
-        android:id="@+id/share_instruction"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_above="@+id/qr_image_panel"
-        android:layout_alignEnd="@+id/qr_image_panel"
-        android:layout_alignLeft="@+id/qr_image_panel"
-        android:layout_alignRight="@+id/qr_image_panel"
-        android:layout_alignStart="@+id/qr_image_panel"
-        android:paddingBottom="24sp"
-        android:paddingTop="16sp"
-        android:text="@string/share_message"
-        android:textColor="@color/text_color_primary"
-        android:textSize="16sp" />
-
-    <LinearLayout
-        android:id="@+id/qr_image_panel"
-        android:layout_width="300dp"
-        android:layout_height="300dp"
-        android:layout_centerHorizontal="true"
-        android:layout_centerInParent="true"
-        android:background="@color/black"
-        android:padding="10dp">
-
-        <ImageView
-            android:id="@+id/qr_image"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent"
-            android:background="@null" />
-
-    </LinearLayout>
 
     <LinearLayout
         android:layout_width="match_parent"
@@ -53,5 +22,33 @@
 
     </LinearLayout>
 
+    <ImageView
+        android:id="@+id/qr_image"
+        android:layout_width="300dp"
+        android:layout_height="300dp"
+        android:layout_centerHorizontal="true"
+        android:layout_centerVertical="true"
+
+        android:gravity="center"
+        android:padding="@dimen/padding_small"
+        android:scaleType="fitCenter" />
+
+    <TextView
+        android:id="@+id/share_instruction"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_above="@+id/qr_image"
+        android:layout_alignEnd="@+id/qr_image"
+        android:layout_alignLeft="@+id/qr_image"
+        android:layout_alignParentTop="true"
+        android:layout_alignRight="@+id/qr_image"
+        android:layout_alignStart="@+id/qr_image"
+        android:gravity="center"
+        android:paddingBottom="24sp"
+        android:paddingTop="16sp"
+        android:text="@string/share_message"
+        android:textColor="@color/text_color_primary"
+        android:textSize="16sp" />
+
 
 </RelativeLayout>
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