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Error unexpected null value #23

Open salehmalik121 opened 3 years ago

salehmalik121 commented 3 years ago

when I use if statement to validate talking about this if statement: movetoHome(BuildContext context) async { if (_formKey.currentState!.validate()) { setState(() { changebutton = true; }); await Future.delayed(Duration(seconds: 1)); await Navigator.pushNamed(context, Myroutes.homeRoute); setState(() { changebutton = false; }); } }

    1. If I run using f5 it takes me to breaking point in feedback.dart at line 107 "return Future.value();"
  1. if I run using terminal it gives me this error: Error: Unexpected null value. at Object.throw_ [as throw] (http://localhost:53848/dart_sdk.js:5348:11) at Object.nullCheck (http://localhost:53848/dart_sdk.js:5681:30) at login_page._LoginPageState.new.movetoHome (http://localhost:53848/packages/learning/pages/login_page.dart.lib.js:644:28) at movetoHome.next () at runBody (http://localhost:53848/dart_sdk.js:39250:34) at Object._async [as async] (http://localhost:53848/dart_sdk.js:39281:7) at login_page._LoginPageState.new.movetoHome (http://localhost:53848/packages/learning/pages/login_page.dart.lib.js:643:20) at http://localhost:53848/packages/learning/pages/login_page.dart.lib.js:677:569 at ink_well._InkResponseState.new.[_handleTap] (http://localhost:53848/packages/flutter/src/material/icon_button.dart.lib.js:50393:31)
    at tap.TapGestureRecognizer.new.invokeCallback (http://localhost:53848/packages/flutter/src/gestures/recognizer.dart.lib.js:194:18)
    at tap.TapGestureRecognizer.new.handleTapUp (http://localhost:53848/packages/flutter/src/gestures/tap.dart.lib.js:408:40) at tap.TapGestureRecognizer.new.[_checkUp] (http://localhost:53848/packages/flutter/src/gestures/tap.dart.lib.js:214:12) at tap.TapGestureRecognizer.new.handlePrimaryPointer (http://localhost:53848/packages/flutter/src/gestures/tap.dart.lib.js:160:23)
    at tap.TapGestureRecognizer.new.handleEvent (http://localhost:53848/packages/flutter/src/gestures/recognizer.dart.lib.js:449:16) at pointer_router.PointerRouter.new.[_dispatch] (http://localhost:53848/packages/flutter/src/gestures/pointer_router.dart.lib.js:93:9)
    at http://localhost:53848/packages/flutter/src/gestures/pointer_router.dart.lib.js:128:26 at LinkedMap.new.forEach (http://localhost:53848/dart_sdk.js:26346:11) at pointer_router.PointerRouter.new.[_dispatchEventToRoutes] (http://localhost:53848/packages/flutter/src/gestures/pointer_router.dart.lib.js:125:29) at pointer_router.PointerRouter.new.route (http://localhost:53848/packages/flutter/src/gestures/pointer_router.dart.lib.js:117:37)
    at binding$5.WidgetsFlutterBinding.new.handleEvent (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:389:26)
    at binding$5.WidgetsFlutterBinding.new.dispatchEvent (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:372:24)
    at binding$5.WidgetsFlutterBinding.new.dispatchEvent (http://localhost:53848/packages/flutter/src/rendering/layer.dart.lib.js:5376:13)
    at binding$5.WidgetsFlutterBinding.new.[_handlePointerEventImmediately] (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:343:14) at binding$5.WidgetsFlutterBinding.new.handlePointerEvent (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:316:43) at binding$5.WidgetsFlutterBinding.new.[_flushPointerEventQueue] (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:305:14) at binding$5.WidgetsFlutterBinding.new.[_handlePointerDataPacket] (http://localhost:53848/packages/flutter/src/gestures/binding.dart.lib.js:295:65) at Object.invoke1 (http://localhost:53848/dart_sdk.js:186355:7) at _engine.EnginePlatformDispatcher..invokeOnPointerDataPacket (http://localhost:53848/dart_sdk.js:166281:15) at _engine.PointerBinding..[_onPointerData] (http://localhost:53848/dart_sdk.js:166941:49) at http://localhost:53848/dart_sdk.js:167399:28 at http://localhost:53848/dart_sdk.js:167352:16 at http://localhost:53848/dart_sdk.js:167045:11
amirhsn commented 3 years ago

please provide the full code, this is hard to me to understand what the problem you're facing, but from the error message, it says that your function is returning a null value, but the forward sink need to be fulfilled by a non null value, because the type is Future