In order to ensure that libraries follow the latest OEM behavior, the default page transition builders now use `ZoomPageTransitionsBuilder` on all platforms (excluding iOS and macOS) instead of `FadeUpwardsPageTransitionsBuilder`.
Original behavior
The `FadeUpwardsPageTransitionsBuilder` (provided with the first Flutter release), defined a page transition that's similar to the one provided by Android O. This page transitions builder will eventually be deprecated on Android, as per Flutter's deprecation policy.
New behavior
`PageTransitionsBuilder`s defined in `PageTransitionsTheme._defaultBuilders` have changed from `FadeUpwardsPageTransitionsBuilder` to `ZoomPageTransitionsBuilder` for `TargetPlatform.android`, `TargetPlatform.linux` and `TargetPlatform.windows`.
- Who is affected
- Applications and packages relying on the previous behaviour or signature. Code that uses ZoomPageTransitionsBuilder, FadeUpwardsPageTransitionsBuilder, TargetPlatform and related APIs.
- Practical impact
- Behaviour or API differences that can break builds or change runtime behaviour.
- What action should I take?
- Follow the official migration guide below, update affected call sites, run `dart fix --apply` where a fix is available, then run your tests.
Before and after (from the official guide)
| 1 | MaterialApp( | |
| 2 | − | theme: ThemeData(colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple)), |
| 3 | ) |
| 1 | MaterialApp( | |
| 2 | + | theme: ThemeData( |
| 3 | + | pageTransitionsTheme: const PageTransitionsTheme( |
| 4 | + | builders: <TargetPlatform, PageTransitionsBuilder>{ |
| 5 | + | TargetPlatform.android: FadeUpwardsPageTransitionsBuilder(), // Apply this to every platforms you need. |
| 6 | + | }, |
| 7 | + | ), |
| 8 | + | ), |
| 9 | ) |
Raw before / after
MaterialApp( theme: ThemeData(colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple)), )
MaterialApp(
theme: ThemeData(
pageTransitionsTheme: const PageTransitionsTheme(
builders: <TargetPlatform, PageTransitionsBuilder>{
TargetPlatform.android: FadeUpwardsPageTransitionsBuilder(), // Apply this to every platforms you need.
},
),
),
)Official migration guide (excerpt, © The Flutter Authors, CC BY 3.0)
If you want to switch back to the previous page transition builder
(FadeUpwardsPageTransitionsBuilder), you should define builders
explicitly for the target platforms.
Code before migration:
MaterialApp(
theme: ThemeData(colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple)),
)Code after migration:
MaterialApp(
theme: ThemeData(
pageTransitionsTheme: const PageTransitionsTheme(
builders: <TargetPlatform, PageTransitionsBuilder>{
TargetPlatform.android: FadeUpwardsPageTransitionsBuilder(), // Apply this to every platforms you need.
},
),
),
)If you want to apply the same page transition builder to all platforms:
MaterialApp(
theme: ThemeData(
pageTransitionsTheme: PageTransitionsTheme(
builders: Map<TargetPlatform, PageTransitionsBuilder>.fromIterable(
TargetPlatform.values,
value: (dynamic _) => const FadeUpwardsPageTransitionsBuilder(),
),
),
),
)
Tests migration
If you used to try to find widgets but failed with Too many elements using the new transition, and saw errors similar to the following:
══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following StateError was thrown running a test:
Bad state: Too many elements
When the exception was thrown, this was the stack:
#0 Iterable.single (dart:core/iterable.dart:656:24)
#1 WidgetController.widget (package:flutter_test/src/controller.dart:69:30)
#2 main.<anonymous closure> (file:///path/to/your/test.dart:1:2)You should migrate your tests by using the
descendant scope for Finders with the specific widget type.
Below is the example of DataTable's test:
Test before migration:
final Finder finder = find.widgetWithIcon(Transform, Icons.arrow_upward);Test after migration:
final Finder finder = find.descendant(
of: find.byType(DataTable),
matching: find.widgetWithIcon(Transform, Icons.arrow_upward),
);Widgets that typically need to migrate the finder scope are:
Transform, FadeTransition, ScaleTransition, and ColoredBox.
AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.Listed in the official breaking-changes index (docs.flutter.dev/release/breaking-changes).
An official announcement or migration guide documents an intended behaviour or API change. A verified source change (git diff) shows code changed but does not by itself prove a public API is breaking. AI interpretations are labelled and never used to classify a change.
- Source commit
- b3045439b7c0
- Source last updated
- Oct 21, 2026
- Last synchronized
- Oct 21, 2026
- Publication status
- published
Publication history
- Oct 21, 2026, 8:31 PM: new → published (ingestion) — Backed by an official breaking-change/migration guide.
AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.