material_ui TextTheme conflict after Flutter/package update - previously working [google_fonts]

Steps to reproduce

Try to run the following code
Compilation error

Expected results

Expected result: ThemeData.textTheme should accept GoogleFonts.pangolinTextTheme() without a type mismatch, as it did previously.

Actual results

The argument type 'TextTheme' can't be assigned to the parameter type 'TextTheme?'.

Code sample

import 'package:material_ui/material_ui.dart';
import 'package:google_fonts/google_fonts.dart';

void main() {
  runApp(
    MaterialApp(
      theme: ThemeData(
        textTheme: GoogleFonts.pangolinTextTheme(),
      ),
      home: const Scaffold(
        body: Center(
          child: Text('Hello'),
        ),
      ),
    ),
  );
}

Screenshots or Video

Screenshots / Video demonstration

Logs

The argument type 'TextTheme' can't be assigned to the parameter type 'TextTheme?'.

Flutter Doctor output

Doctor output

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel master, 3.48.0-1.0.pre-178, on macOS 26.6.1 25G76 darwin-arm64, locale en-IN)
[✓] Android toolchain - develop for Android devices (Android SDK version 36.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 26.6)
[✓] Chrome - develop for the web
[✓] Connected device (2 available)
[✓] Network resources                

• No issues found!

Thanks for the detailed report. Routing to the design team for evaluation.

Thanks for the fast triage!

The compatibility bridge should be able to help with this, it will map over ThemeData properties to cover the gap for dependencies that have not migrated yet.

google_fonts needs to be migrated to use the new design packages, we should be able to do that soon.

But compatibility bridge won't help because it takes modern Theme and converts it to legacy Theme, so maybe we have to do what compatibility bridge does. something like:

MaterialApp(
      title: AppConfig.appName,
      builder: (context, child) =>
          legacy.Theme(data: AppTheme.lightTheme, child: child!),
    )

hope this works.

@Piinks

@Piinks Hey, is this issue currently being worked on? It's my first time here, and I'd be happy to try and help out if it's not a WIP!

I opened the PR, but I’m not sure when it will be approved. If you want to use it, you can add it like this for now:

google_fonts:
git:
url: https://github.com/Segatti/flutter_packages.git
path: packages/google_fonts

chore: Migrate to flutter 3.47.0

Add design migration guide (#13821)

[google_fonts] Migrate to material_ui & cupertino_ui (flutter#13006)

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.

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material_ui TextTheme conflict after Flutter/package update - previously working [google_fonts] #191067

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Actual results

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Logs

Flutter Doctor output

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material_ui TextTheme conflict after Flutter/package update - previously working [google_fonts] #191067

Description

Steps to reproduce

Expected results

Actual results

Code sample

Screenshots or Video

Logs

Flutter Doctor output

Activity

mbcorona commented on Aug 13, 2026

piedcipher commented on Aug 13, 2026

Piinks commented on Aug 13, 2026

suhail-121 commented on Aug 15, 2026

Jerome-Jumah commented on Aug 17, 2026

Segatti commented on Aug 18, 2026

4 remaining items

github-actions commented on Oct 12, 2026

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