DiagnosticableMixin is removed in new Flutter versions (stable)

[danilofuchs]

I am receiving these errors in Flutter 1.20 (stable):

../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:26: Error: Type 'DiagnosticableMixin' not found.
class PictureStream with DiagnosticableMixin {
                         ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:44: Error: Type 'DiagnosticableMixin' not found.
abstract class PictureStreamCompleter with DiagnosticableMixin {
                                           ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:7: Error: The type 'DiagnosticableMixin' can't be mixed in.
class PictureStream with DiagnosticableMixin {
      ^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:16: Error: The type 'DiagnosticableMixin' can't be mixed in.
abstract class PictureStreamCompleter with DiagnosticableMixin {
               ^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:167:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(properties);
          ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:171:30: Error: The method 'toStringShort' isn't defined for the class 'PictureStreamCompleter'.
 - 'PictureStreamCompleter' is from 'package:flutter_svg/src/picture_stream.dart' ('../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart').
Try correcting the name to the name of an existing method, or defining a method named 'toStringShort'.
      ifPresent: _completer?.toStringShort(),
                             ^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:266:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(description);
          ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:26: Error: Type 'DiagnosticableMixin' not found.
class PictureStream with DiagnosticableMixin {
                         ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:44: Error: Type 'DiagnosticableMixin' not found.
abstract class PictureStreamCompleter with DiagnosticableMixin {
                                           ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:88:7: Error: The type 'DiagnosticableMixin' can't be mixed in.
class PictureStream with DiagnosticableMixin {
      ^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:192:16: Error: The type 'DiagnosticableMixin' can't be mixed in.
abstract class PictureStreamCompleter with DiagnosticableMixin {
               ^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:167:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(properties);
          ^^^^^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:171:30: Error: The method 'toStringShort' isn't defined for the class 'PictureStreamCompleter'.
 - 'PictureStreamCompleter' is from 'package:flutter_svg/src/picture_stream.dart' ('../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart').
Try correcting the name to the name of an existing method, or defining a method named 'toStringShort'.
      ifPresent: _completer?.toStringShort(),
                             ^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/flutter_svg-0.17.4/lib/src/picture_stream.dart:266:11: Error: Superclass has no method named 'debugFillProperties'.
    super.debugFillProperties(description);
          ^^^^^^^^^^^^^^^^^^^

This is similar to this issue: Realank/flutter_datetime_picker#155

[merfire]

Have you tried updating to version 0.18.0 ?
I think that will fix your issue.

[dnfield]

You must use at least 0.18.0

[Dannark]

What do you guys mean when you say to update it to 0.18.0?

My flutter is 1.20 and Dart 2.9
Who should be in 0.18?

PS C:\Users\User\flutter\BWO> flutter --version
Flutter 1.20.0 • channel stable •
https://github.com/flutter/flutter.git
Framework • revision 840c9205b3 (21 hours ago) • 2020-08-04 20:55:12-0700
Engine • revision c8e3b94853
Tools • Dart 2.9.0

[dnfield]

Flutter_svg ^0.18.0

[danilofuchs]

Thanks! 0.18.0 fixed it. My bad for not checking the changelog 🙈
pub.dev interface for changes is quite confusing (it's not clear the changes section is attached to 0.18.0):

[GreyNadeOfficial]

after finding the solution for 2 days, this stupid mistake i made?
wow

[the-anup-das]

To solve this is done the following updates in pubspec.yaml
Flutter_svg: ^0.18.0
flutter_html: ^1.0.2
flutter_widget_from_html: 0.4.3

[NeighborhoodCoding]

how to update? should I command in powshell? (windows10)

PS C:\WINDOWS\system32> flutter pub get
Error: No pubspec.yaml file found.
This command should be run from the root of your Flutter project.
Do not run this command from the root of your git clone of Flutter.

[kovalyovi]

how to update? should I command in powshell? (windows10)

PS C:\WINDOWS\system32> flutter pub get
Error: No pubspec.yaml file found.
This command should be run from the root of your Flutter project.
Do not run this command from the root of your git clone of Flutter.

You should go to your flutter project by doing
cd <YOUR_PROJECT_ROOT_PATH> and then running flutter pub get in there (after you updated the pubspec.yaml with a newer flutter_svg ^0.18.1 version.

[anirudh-softprodigy]

To solve this is done the following updates in pubspec.yaml
Flutter_svg: ^0.18.0
flutter_html: ^1.0.2
flutter_widget_from_html: 0.4.3

upgrading - flutter_html: ^1.0.2 fixed it for me

[mahatodebashish]

Flutter_svg ^0.18.0

Thank dmfield