Introduce `TabBar.textScaler` for tab label upper text scale limit

TahaTesser commented 3 weeks ago

fixes Tab is hardcoding the height of the icons and the text

Description

This PR introduces TabBar.textScaler to provide upper text scale limit for tab label.

Code sample

expand to view the code sample

```dart import 'package:flutter/material.dart'; void main() => runApp(const MyApp()); class MyApp extends StatelessWidget { const MyApp({super.key}); @override Widget build(BuildContext context) { return MaterialApp( debugShowCheckedModeBanner: false, home: MediaQuery( data: const MediaQueryData(textScaler: TextScaler.linear(3.0)), child: DefaultTabController( length: 3, child: Scaffold( appBar: AppBar( title: const Text('Sample'), bottom: const TabBar( textScaler: TextScaler.linear(2.0), tabs: [ Tab(text: 'Tab 1'), Tab(text: 'Tab 2'), Tab(text: 'Tab 3'), ], ), ), floatingActionButton: Builder(builder: (BuildContext context) { return FloatingActionButton( onPressed: () { print(MediaQuery.textScalerOf(context)); }, child: const Icon(Icons.add), ); }), ), ), ), ); } } ```

Without `TabBar.textScaler`

Screenshot 2024-04-30 at 13 46 10

With `TabBar.textScaler`

              bottom: const TabBar(
                textScaler: TextScaler.linear(2.0),
                tabs: <Widget>[
                  Tab(text: 'Tab 1'),
                  Tab(text: 'Tab 2'),
                  Tab(text: 'Tab 3'),
                ],
              ),

Screenshot 2024-04-30 at 14 04 22

Pre-launch Checklist

[x] I read the Contributor Guide and followed the process outlined there for submitting PRs.
[x] I read the Tree Hygiene wiki page, which explains my responsibilities.
[x] I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
[x] I signed the CLA.
[x] I listed at least one issue that this PR fixes in the description above.
[ ] I updated/added relevant documentation (doc comments with ///).
[x] I added new tests to check the change I am making, or this PR is test-exempt.
[ ] I followed the breaking change policy and added Data Driven Fixes where supported.
[x] All existing and new tests are passing.

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TahaTesser commented 2 weeks ago

I checked the Google testing failures, and they appear to be legitimate, There are existing customers that expect to be able to create the before image in this PR.

@TahaTesser maybe there is a way we can make this opt-in?

Added TabBar.textScaler which can override the text scale for tab label, optionally. This ensures the existing tests are not effected.

EditableText and SelectableText also contain parameter to override their text scale.

Updated the PR and description as well. Please let me know what do you think.

TahaTesser commented 1 week ago

@Piinks Thanks for review! Rebasing just in case. :)

flutter / flutter