reworked operation (#12)

Reviewed-on: #12
Co-authored-by: Mark M2 Macbook <marco@catelli.it>
Co-committed-by: Mark M2 Macbook <marco@catelli.it>

lib/core/widgets/image_viewer_widget.dart

@@ -1,5 +1,6 @@
 import 'dart:typed_data';
 import 'package:flutter/material.dart';
+import 'package:flux/core/utils/extensions.dart';
 import 'package:flux/core/utils/functions.dart';
 
 class ImageViewerWidget extends StatelessWidget {
@@ -36,8 +37,8 @@ class ImageViewerWidget extends StatelessWidget {
                       return const CircularProgressIndicator();
                     }
                     if (snapshot.hasError) {
-                      return const Text(
-                        "Errore caricamento immagine (Permessi negati?)",
+                      return Text(
+                        context.l10n.imageViewerWidgetErrorOpening,
                         style: TextStyle(color: Colors.red),
                       );
                     }