add proximity uuid for ios

lib/Screens/Visit/visit.dart

@@ -129,11 +129,20 @@ class _VisitPageState extends State<VisitPage> with WidgetsBindingObserver {
               'bluetoothEnabled=${controller.bluetoothEnabled}');
       return;
     }
-    final regions = <Region>[
-      Region(
-          identifier: 'MyMuseumB'
-      ),
-    ];
+
+    final regions = <Region>[];
+
+    if (Platform.isIOS) {
+      // iOS platform, at least set identifier and proximityUUID for region scanning
+      regions.add(Region(
+          identifier: 'MyMuseumB',
+          proximityUUID: '01122334-4556-6778-899A-ABBCCDDEEFF0'));
+    } else {
+      // Android platform, it can ranging out of beacon that filter all of Proximity UUID
+      regions.add(Region(identifier: 'MyMuseumB'));
+    }
+
+
 
     if (_streamRanging != null) {
       if (_streamRanging!.isPaused) {