Flutter build fails after upgrade to flow_builder-0.0.7

[GerhardMalan]

Describe the bug
Flutter build fails after upgrade to flow_builder-0.0.7 from flow_builder-0.0.6.

To Reproduce
Steps to reproduce the behavior:

1. Upgrade to flow_builder-0.0.7 from flow_builder-0.0.6.
2. Run app (F5)
3. Build fails with error messages below:
4. Fixed the problem by directly editing C:\sdk\flutter.pub-cache\hosted\pub.dartlang.org\flow_builder-0.0.7\lib\flow_builder.dart, lines 367 and 372, adding null operator [?] after WidgetsBinding.instance?

---

/C:/sdk/flutter/.pub-cache/hosted/pub.dartlang.org/flow_builder-0.0.7/lib/flow_builder.dart:367:36: Error: Method 'handlePopRoute' cannot be called on 'WidgetsBinding?' because it is potentially null.

• 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('/C:/sdk/flutter/packages/flutter/lib/src/widgets/binding.dart').
  package:flutter/…/widgets/binding.dart:1
  Try calling using ?. instead.
  return WidgetsBinding.instance.handlePopRoute();
  ^^^^^^^^^^^^^^
  /C:/sdk/flutter/.pub-cache/hosted/pub.dartlang.org/flow_builder-0.0.7/lib/flow_builder.dart:372:38: Error: Method 'handlePushRoute' cannot be called on 'WidgetsBinding?' because it is potentially null.

• 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('/C:/sdk/flutter/packages/flutter/lib/src/widgets/binding.dart').
  package:flutter/…/widgets/binding.dart:1
  Try calling using ?. instead.
  return WidgetsBinding.instance.handlePushRoute(arguments);

[felangel]

Hi @GerhardMalan 👋
Thanks for opening an issue!

I think this must have been a subtle breaking change introduced in Flutter 3.0.0. Can you upgrade to the latest stable channel of Flutter (3.0.0) and let me know if the issue persists? Thanks and sorry for the inconvenience!

[GerhardMalan]

Sure, we'll have a go. Our app has a fair few library imports, so there may well be other conflicts. Thanks for the quick response.

I'll get back to you after upgrading Felix.

[GerhardMalan]

Ok, that's fixed it, thanks. Have two libraries (latest versions) that compile with warnings due to the now unnecessary null-aware operators on WidgetsBinding.instance, but that's not a big deal for now:

• flutter_typeahead-3.2.5,
• cached_network_image-3.2.0

Thanks for the help and quick response Felix!

[felangel]

Ok, that's fixed it, thanks. Have two libraries (latest versions) that compile with warnings due to the now unnecessary null-aware operators on WidgetsBinding.instance, but that's not a big deal for now:

• flutter_typeahead-3.2.5,
• cached_network_image-3.2.0

Thanks for the help and quick response Felix!

Awesome, glad to hear it!