'Flutter 'owner!._debugCurrentBuildTarget == this': is not true. #87

I am getting the error when I try to load the pdf from url. It shows the number of pages of pdf but then it crashes.

Using plugin - https://pub.dev/packages/advance_pdf_viewer

════════════════════════════════════════════════════════════════════════════════════════════════════
I/flutter (28488): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (28488): The following assertion was thrown while rebuilding dirty elements:
I/flutter (28488): 'package:flutter/src/widgets/framework.dart': Failed assertion: line 4371 pos 14:
I/flutter (28488): 'owner!._debugCurrentBuildTarget == this': is not true.
I/flutter (28488):
I/flutter (28488): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter (28488): more information in this error message to help you determine and fix the underlying cause.
I/flutter (28488): In either case, please report this assertion by filing a bug on GitHub:
I/flutter (28488):   https://github.com/flutter/flutter/issues/new?template=BUG.md
I/flutter (28488):
I/flutter (28488): The relevant error-causing widget was:
I/flutter (28488):   PDFViewer
I/flutter (28488):   
lib/…/panSignatureScreens/pan_screen.dart:156
I/flutter (28488):
I/flutter (28488): When the exception was thrown, this was the stack:
I/flutter (28488): #2      Element.rebuild.<anonymous closure> 
package:flutter/…/widgets/framework.dart:4371
I/flutter (28488): #3      Element.rebuild 
package:flutter/…/widgets/framework.dart:4374
I/flutter (28488): #4      BuildOwner.buildScope 
package:flutter/…/widgets/framework.dart:2777
I/flutter (28488): #5      WidgetsBinding.drawFrame 
package:flutter/…/widgets/binding.dart:906
I/flutter (28488): #6      RendererBinding._handlePersistentFrameCallback 
package:flutter/…/rendering/binding.dart:309
I/flutter (28488): #7      SchedulerBinding._invokeFrameCallback 
package:flutter/…/scheduler/binding.dart:1117
I/flutter (28488): #8      SchedulerBinding.handleDrawFrame 
package:flutter/…/scheduler/binding.dart:1055
I/flutter (28488): #9      SchedulerBinding._handleDrawFrame 
package:flutter/…/scheduler/binding.dart:971
I/flutter (28488): #13     _invoke  (dart:ui/hooks.dart:251:10))
I/flutter (28488): #14     _drawFrame  (dart:ui/hooks.dart:209:3))

my usage - inside a Column(children:[])

new Expanded(
                  child: Container(
                    child: PDFViewer(
                      document: document,
                    ),
                    decoration: BoxDecoration(
                      border: Border.all(color: Colors.black),
                    ),
                  ),
                ),


Solution 1:[1]

I had the same issue and the problem was I had called the class inside the same class. See the body: below. Replacing it with another widget fixed the issue.

class DicePage extends StatelessWidget {
      @override
      Widget build(BuildContext context) {
        return MaterialApp(
                   home: Scaffold(
                   backgroundColor: Colors.red,
                   appBar: AppBar(
                             title: Text('Dicee'),
                             backgroundColor: Colors.red,
                           ),
                    body: DicePage(),
      ),
    );
  }
}

Solution 2:[2]

I just had a similiar error:

???????? Exception caught by widgets library ???????????????????????????????????
The following StackOverflowError was thrown building Container:
Stack Overflow

The relevant error-causing widget was
Container
lib/widgets/profile_wiget.dart:9
When the exception was thrown, this was the stack
#0      new _HashMap (dart:collection-patch/collection_patch.dart)
#1      new HashMap (dart:collection-patch/collection_patch.dart:33:22)
#2      RegExp._cache (dart:core-patch/regexp_patch.dart:109:11)
#3      RegExp._cache (dart:core-patch/regexp_patch.dart)
#4      new RegExp (dart:core-patch/regexp_patch.dart:17:31)
...
????????????????????????????????????????????????????????????????????????????????

???????? Exception caught by widgets library ???????????????????????????????????
'package:flutter/src/widgets/framework.dart': Failed assertion: line 4371 pos 14: 'owner!._debugCurrentBuildTarget == this': is not true.
The relevant error-causing widget was
ProfileWidget
lib/widgets/profile_wiget.dart:10
????????????????????????????????????????????????????????????????????????????????

???????? Exception caught by widgets library ???????????????????????????????????
'package:flutter/src/widgets/framework.dart': Failed assertion: line 4371 pos 14: 'owner!._debugCurrentBuildTarget == this': is not true.
The relevant error-causing widget was
Container
lib/widgets/profile_wiget.dart:9
????????????????????????????????????????????????????????????????????????????????

It might be another reason since I got a stackoverflow, but my answer will hopefully help others who search this error message.
My problem was that I made a widget returning an instance of itself (I named two classes the same):

class ProfileWidget extends StatelessWidget {
  final Profile profile = Profile(name: 'Someone');
  @override
  Widget build(BuildContext context) {
    return Container(
      child: (profile.isAnon) ? AnonProfileWidget() : ProfileWidget(), 
    );
  }
}

I solved it by simply renaming one class.

Solution 3:[3]

For me that was happening while I had an widget instead of sliver in CustomScrollView

Solution 4:[4]

Are you using FirebaseMessaging? If so, it could be a conflict of advance_pdf_viewer with onBackgroundMessage of FirebaseMessaging.

Solution 5:[5]

Yes! There is a conflict with advance_pdf_viewer only if you are using Firebase Cloud Messaging Service's Background Message handler.

For example if you have something like :

Future<void> initNotifs() async {
    FirebaseMessaging.onMessage.listen((RemoteMessage message) async {
      print("onMessage: $message");
    });
    final FirebaseMessaging messaging;
    messaging = FirebaseMessaging.instance;
    await messaging.getToken().then((c) => print(c));
    await messaging
        .subscribeToTopic('general')
        .then((value) => print('subscribed to general'));
     FirebaseMessaging.onBackgroundMessage(
         PushNotificationsHandler.firebaseMessagingBackgroundHandler);
  }

Comment the below code and/Or config the notifications in Locators/Some other View:

FirebaseMessaging.onBackgroundMessage(
             PushNotificationsHandler.firebaseMessagingBackgroundHandler);

Ps: PushNotificationsHandler is Another Class.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Ariel Magbanua
Solution 2 Nicklas Bocksberger
Solution 3 Mateusz Pietras
Solution 4 David
Solution 5 Rohit Daftari