Fixed Share dialog for iPadOs

lib/view/pages/more/share/selectShareTypeDialog.dart

@@ -22,12 +22,11 @@ class SelectShareTypeDialog extends StatelessWidget {
           ),
           ListTile(
             leading: const Icon(Icons.link_outlined),
-            title: const Text("Per Link"),
+            title: const Text("Per Link teilen"),
             trailing: const Icon(Icons.arrow_right),
             onTap: () {
-              final box = context.findRenderObject() as RenderBox?;
               Share.share(
-                  sharePositionOrigin: box!.localToGlobal(Offset.zero) & box.size,
+                  sharePositionOrigin: Rect.fromLTWH(0, 0, MediaQuery.of(context).size.width, MediaQuery.of(context).size.height / 2),
                   subject: "App Teilen",
                   "Hol dir die für das Marianum maßgeschneiderte App:"
                       "\n\nAndroid: https://play.google.com/store/apps/details?id=eu.mhsl.marianum.mobile.client "