'Method '_add from Integer' was called on Null' error on launch of the app

[Max Tsyba]

This error occurs on every launch of the app, even if there's no SliverExpandableList widget built on the screen.

Here's the log:

I/flutter ( 5599): The method '_addFromInteger' was called on null.
I/flutter ( 5599): Receiver: null
I/flutter ( 5599): Tried calling: _addFromInteger(1)
I/flutter ( 5599): 
I/flutter ( 5599): The relevant error-causing widget was:
I/flutter ( 5599):   Feed-[LabeledGlobalKey<FeedState>#fb6be]
I/flutter ( 5599):   file:///home/max/%D0%9A%D0%BE%D0%B4/Flutter%20Projects/Feed-master/lib/main.dart:257:15
I/flutter ( 5599): 
I/flutter ( 5599): When the exception was thrown, this was the stack:
I/flutter ( 5599): #0      Object.noSuchMethod (dart:core-patch/object_patch.dart:53:5)
I/flutter ( 5599): #1      int.+ (dart:core-patch/integers.dart:12:38)
I/flutter ( 5599): #2      SliverExpandableChildDelegate._buildSectionRealIndexes (package:sticky_and_expandable_list/src/sliver_expandable_list.dart:168:22)
I/flutter ( 5599): #3      new SliverExpandableChildDelegate (package:sticky_and_expandable_list/src/sliver_expandable_list.dart:69:30)

[tp7309]

Ensure all section object in sectionList is not null.
try flutter clean , then run your project again.

[Max Tsyba]

Ensure all section object in sectionList is not null.
try flutter clean , then run your project again.

Works now! 👍