Not working on Null Safety | Useless

[HKTareen]

Error: MissingPluginException(No implementation found for method scanQR on channel com.aeologic.adhoc.qrutils) at Object.throw [as throw] (http://localhost:51398/dart_sdk.js:5405:11) at MethodChannel._invokeMethod (http://localhost:51398/packages/flutter/src/services/restoration.dart.lib.j s:1618:21) at _invokeMethod.next () at http://localhost:51398/dart_sdk.js:43063:33 at _RootZone.runUnary (http://localhost:51398/dart_sdk.js:42919:58) at _FutureListener.thenAwait.handleValue (http://localhost:51398/dart_sdk.js:37493:29) at handleValueCallback (http://localhost:51398/dart_sdk.js:38088:49) at Function._propagateToListeners (http://localhost:51398/dart_sdk.js:38126:17) at _Future.new.[_completeWithValue] (http://localhost:51398/dart_sdk.js:37955:23) at async._AsyncCallbackEntry.new.callback (http://localhost:51398/dart_sdk.js:37991:35) at Object._microtaskLoop (http://localhost:51398/dart_sdk.js:43223:13) at _startMicrotaskLoop (http://localhost:51398/dart_sdk.js:43229:13) at http://localhost:51398/dart_sdk.js:38359:9