NFC Check added

lib/pages/BookAppointment/QRCode.dart

@@ -62,13 +62,9 @@ class _QRCodeState extends State<QRCode> {
     // _bytes = base64.decode(widget.appoQR.split(',').last);
     widget.authUser = new AuthenticatedUser();
 
-    FlutterNfcKit.nfcAvailability.then((value) {
-      _supportsNFC = (value == NFCAvailability.available);
-    });
-
-    WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
+    // WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
       // startNFCScan();
-    });
+    // });
 
     super.initState();
   }
@@ -113,6 +109,9 @@ class _QRCodeState extends State<QRCode> {
   Widget build(BuildContext context) {
     projectViewModel = Provider.of(context);
     _context = context;
+    FlutterNfcKit.nfcAvailability.then((value) {
+      _supportsNFC = (value == NFCAvailability.available);
+    });
     List<Widget> checkInOptionsList = getCheckInOptionsList(context);
     return AppScaffold(
       appBarTitle: TranslationBase.of(context).onlineCheckIn,
@@ -214,8 +213,10 @@ class _QRCodeState extends State<QRCode> {
     optionsList.add(
       InkWell(
         onTap: () {
-          if (projectViewModel.havePrivilege(80)) {
+          if (projectViewModel.havePrivilege(80) && _supportsNFC) {
             startNFCScan();
+          } else {
+            Utils.showErrorToast(TranslationBase.of(context).NFCNotSupported);
           }
         },
         child: MedicalProfileItem(