feat: add onEnd to AnimatedCrossFade#181455
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This pull request introduces an onEnd callback to the AnimatedCrossFade widget, which is triggered upon the completion of the cross-fade animation. The implementation correctly adds a status listener to the animation controller and invokes the callback when the animation is completed or dismissed. The changes are accompanied by a comprehensive set of tests that verify the new functionality in forward, reverse, and repeated animation scenarios. My feedback focuses on improving the readability and maintainability of the new tests by reducing code duplication, in line with the repository's style guide.
| testWidgets('AnimatedCrossFade onEnd callback is called when animation completes forward', ( | ||
| WidgetTester tester, | ||
| ) async { | ||
| int onEndCallCount = 0; | ||
|
|
||
| await tester.pumpWidget( | ||
| Directionality( | ||
| textDirection: TextDirection.ltr, | ||
| child: AnimatedCrossFade( | ||
| firstChild: const SizedBox(width: 100.0, height: 100.0), | ||
| secondChild: const SizedBox(width: 200.0, height: 200.0), | ||
| crossFadeState: CrossFadeState.showFirst, | ||
| duration: const Duration(milliseconds: 200), | ||
| onEnd: () { | ||
| onEndCallCount++; | ||
| }, | ||
| ), | ||
| ), | ||
| ); | ||
|
|
||
| expect(onEndCallCount, 0); | ||
|
|
||
| // Transition to showSecond. | ||
| await tester.pumpWidget( | ||
| Directionality( | ||
| textDirection: TextDirection.ltr, | ||
| child: AnimatedCrossFade( | ||
| firstChild: const SizedBox(width: 100.0, height: 100.0), | ||
| secondChild: const SizedBox(width: 200.0, height: 200.0), | ||
| crossFadeState: CrossFadeState.showSecond, | ||
| duration: const Duration(milliseconds: 200), | ||
| onEnd: () { | ||
| onEndCallCount++; | ||
| }, | ||
| ), | ||
| ), | ||
| ); | ||
|
|
||
| // Pump halfway through animation. | ||
| await tester.pump(const Duration(milliseconds: 100)); | ||
| expect(onEndCallCount, 0); | ||
|
|
||
| // Pump to complete animation and settle. | ||
| await tester.pumpAndSettle(); | ||
| expect(onEndCallCount, 1); | ||
| }); |
There was a problem hiding this comment.
This test contains duplicated code for building the AnimatedCrossFade widget. This can be simplified by extracting the widget creation into a helper function, similar to what's done in the 'AnimatedCrossFade onEnd callback is called for each animation cycle' test. This will make the test more readable and easier to maintain.
testWidgets('AnimatedCrossFade onEnd callback is called when animation completes forward', (
WidgetTester tester,
) async {
int onEndCallCount = 0;
Widget buildWidget(CrossFadeState state) {
return Directionality(
textDirection: TextDirection.ltr,
child: AnimatedCrossFade(
firstChild: const SizedBox(width: 100.0, height: 100.0),
secondChild: const SizedBox(width: 200.0, height: 200.0),
crossFadeState: state,
duration: const Duration(milliseconds: 200),
onEnd: () {
onEndCallCount++;
},
),
);
}
await tester.pumpWidget(buildWidget(CrossFadeState.showFirst));
expect(onEndCallCount, 0);
// Transition to showSecond.
await tester.pumpWidget(buildWidget(CrossFadeState.showSecond));
// Pump halfway through animation.
await tester.pump(const Duration(milliseconds: 100));
expect(onEndCallCount, 0);
// Pump to complete animation and settle.
await tester.pumpAndSettle();
expect(onEndCallCount, 1);
});References
- Code should be optimized for readability. In this case, the test code can be made more readable by reducing duplication. (link)
| testWidgets('AnimatedCrossFade onEnd callback is called when animation completes reverse', ( | ||
| WidgetTester tester, | ||
| ) async { | ||
| int onEndCallCount = 0; | ||
|
|
||
| await tester.pumpWidget( | ||
| Directionality( | ||
| textDirection: TextDirection.ltr, | ||
| child: AnimatedCrossFade( | ||
| firstChild: const SizedBox(width: 100.0, height: 100.0), | ||
| secondChild: const SizedBox(width: 200.0, height: 200.0), | ||
| crossFadeState: CrossFadeState.showSecond, | ||
| duration: const Duration(milliseconds: 200), | ||
| onEnd: () { | ||
| onEndCallCount++; | ||
| }, | ||
| ), | ||
| ), | ||
| ); | ||
|
|
||
| expect(onEndCallCount, 0); | ||
|
|
||
| // Reverse transition to showFirst. | ||
| await tester.pumpWidget( | ||
| Directionality( | ||
| textDirection: TextDirection.ltr, | ||
| child: AnimatedCrossFade( | ||
| firstChild: const SizedBox(width: 100.0, height: 100.0), | ||
| secondChild: const SizedBox(width: 200.0, height: 200.0), | ||
| crossFadeState: CrossFadeState.showFirst, | ||
| duration: const Duration(milliseconds: 200), | ||
| onEnd: () { | ||
| onEndCallCount++; | ||
| }, | ||
| ), | ||
| ), | ||
| ); | ||
|
|
||
| // Pump halfway through animation. | ||
| await tester.pump(const Duration(milliseconds: 100)); | ||
| expect(onEndCallCount, 0); | ||
|
|
||
| // Pump to complete animation and settle. | ||
| await tester.pumpAndSettle(); | ||
| expect(onEndCallCount, 1); | ||
| }); |
There was a problem hiding this comment.
Similar to the previous test, this one also has duplicated code for building the AnimatedCrossFade widget. Extracting this logic into a helper function would improve readability and maintainability.
testWidgets('AnimatedCrossFade onEnd callback is called when animation completes reverse', (
WidgetTester tester,
) async {
int onEndCallCount = 0;
Widget buildWidget(CrossFadeState state) {
return Directionality(
textDirection: TextDirection.ltr,
child: AnimatedCrossFade(
firstChild: const SizedBox(width: 100.0, height: 100.0),
secondChild: const SizedBox(width: 200.0, height: 200.0),
crossFadeState: state,
duration: const Duration(milliseconds: 200),
onEnd: () {
onEndCallCount++;
},
),
);
}
await tester.pumpWidget(buildWidget(CrossFadeState.showSecond));
expect(onEndCallCount, 0);
// Reverse transition to showFirst.
await tester.pumpWidget(buildWidget(CrossFadeState.showFirst));
// Pump halfway through animation.
await tester.pump(const Duration(milliseconds: 100));
expect(onEndCallCount, 0);
// Pump to complete animation and settle.
await tester.pumpAndSettle();
expect(onEndCallCount, 1);
});References
- Code should be optimized for readability. In this case, the test code can be made more readable by reducing duplication. (link)
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Thanks for the wonderful contribution!
Roll Flutter from dfd92b773219 to da72d5936d69 (39 revisions) flutter/flutter@dfd92b7...da72d59 2026-01-29 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[ Tool / Engine ] Cleanup x86 references (#181152)" (flutter/flutter#181643) 2026-01-29 engine-flutter-autoroll@skia.org Roll Skia from 174db42b7300 to 89df65f8324c (2 revisions) (flutter/flutter#181636) 2026-01-29 59215665+davidhicks980@users.noreply.github.com [material/menu_anchor.dart] Add animations to MenuAnchor. (flutter/flutter#176494) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 8e09f8a82251 to 174db42b7300 (6 revisions) (flutter/flutter#181627) 2026-01-28 31859944+LongCatIsLooong@users.noreply.github.com Send statusBarTouch events via dedicated messages (flutter/flutter#179643) 2026-01-28 git@reb0.org test: Improve DropdownMenuFormField tests (flutter/flutter#181369) 2026-01-28 evanwall@buffalo.edu Account for vec3 padding in Metal (flutter/flutter#181563) 2026-01-28 bkonyi@google.com [ Tool / Engine ] Cleanup x86 references (flutter/flutter#181152) 2026-01-28 ybz975218925@gmail.com Fix the issue on macOS where, after a hot restart with multiple windows, unresponsive windows are left behind. (flutter/flutter#180287) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 675444e94bc9 to 8e09f8a82251 (7 revisions) (flutter/flutter#181606) 2026-01-28 engine-flutter-autoroll@skia.org Roll Packages from e37af11 to 1cb2148 (5 revisions) (flutter/flutter#181608) 2026-01-28 codefu@google.com fix: swap app and engine version in vk::ApplicationInfo (flutter/flutter#181432) 2026-01-28 30870216+gaaclarke@users.noreply.github.com Adds impeller backend to skia gold client (flutter/flutter#181503) 2026-01-28 mdebbar@google.com Remove chrome_and_driver dependency where it's not needed (flutter/flutter#178174) 2026-01-28 codefu@google.com chore: Windows_mokey basic_material_app_win__compile !bringup (flutter/flutter#180985) 2026-01-28 116356835+AbdeMohlbi@users.noreply.github.com Fix generating both `settings.gradle` and `settings.gradle.kts` for plugins (flutter/flutter#181592) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 6614f89de521 to 675444e94bc9 (3 revisions) (flutter/flutter#181587) 2026-01-28 104349824+huycozy@users.noreply.github.com Fix `todayBorder` todayBorder color is incorrectly overridden by `todayForegroundColor` in CalendarDatePicker (flutter/flutter#178792) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 8f1695a4b328 to 6614f89de521 (2 revisions) (flutter/flutter#181583) 2026-01-28 34465683+rkishan516@users.noreply.github.com feat: add RoundedSuperellipseInputBorder (flutter/flutter#177220) 2026-01-28 engine-flutter-autoroll@skia.org Roll Dart SDK from 38e351498549 to f10dcbfca98f (2 revisions) (flutter/flutter#181582) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from f424d58e37a3 to 8f1695a4b328 (6 revisions) (flutter/flutter#181577) 2026-01-28 116356835+AbdeMohlbi@users.noreply.github.com Remove unused code paths in `PlatformViewsController.java` (flutter/flutter#181393) 2026-01-28 34465683+rkishan516@users.noreply.github.com feat: add onEnd to AnimatedCrossFade (flutter/flutter#181455) 2026-01-28 1961493+harryterkelsen@users.noreply.github.com Don't pass bounds to saveLayer call when painting ImageFilter (flutter/flutter#181353) 2026-01-28 luanpotter27@gmail.com test: Clarify failure messages on gestures/debug_test.dart (flutter/flutter#181109) 2026-01-27 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from akraNGn2lw4T1msgZ... to adhoq9ouVRh0xzkm3... (flutter/flutter#181571) 2026-01-27 engine-flutter-autoroll@skia.org Roll Dart SDK from 4c7cb0a1d07d to 38e351498549 (4 revisions) (flutter/flutter#181570) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedPadding doesn't crash in 0x0 environment (flutter/flutter#181235) 2026-01-27 ahmedsameha1@gmail.com Make sure that an ImageFiltered doesn't crash at 0x0 environment (flutter/flutter#181067) 2026-01-27 magder@google.com Marks firebase_release_smoke_test to be unflaky (flutter/flutter#181308) 2026-01-27 kazbek.sultanov.doc@gmail.com Fix remove material import box decoration test (flutter/flutter#181253) 2026-01-27 engine-flutter-autoroll@skia.org Roll Skia from c2754838b077 to f424d58e37a3 (8 revisions) (flutter/flutter#181564) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedAlign doesn't crash in 0x0 environment (flutter/flutter#181361) 2026-01-27 ahmedsameha1@gmail.com Make sure that an ImageIcon doesn't crash in 0x0 environment (flutter/flutter#181099) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedContainer doesn't crash in 0x0 environment (flutter/flutter#181198) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedRotation doesn't crash in 0x0 environment (flutter/flutter#181486) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedPositionedDirectional doesn't crash in 0x0 … (flutter/flutter#181451) 2026-01-27 jacksongardner@google.com Merge changelog for 3.38.8. (flutter/flutter#181558) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC bmparr@google.com,stuartmorgan@google.com on the revert to ensure that a human is aware of the problem. ...
feat: add onEnd to AnimatedCrossFade fixes: flutter#180682 ## 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. - [x] 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]. - [x] I followed the [breaking change policy] and added [Data Driven Fixes] where supported. - [x] All existing and new tests are passing.
…r#10923) Roll Flutter from dfd92b773219 to da72d5936d69 (39 revisions) flutter/flutter@dfd92b7...da72d59 2026-01-29 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[ Tool / Engine ] Cleanup x86 references (#181152)" (flutter/flutter#181643) 2026-01-29 engine-flutter-autoroll@skia.org Roll Skia from 174db42b7300 to 89df65f8324c (2 revisions) (flutter/flutter#181636) 2026-01-29 59215665+davidhicks980@users.noreply.github.com [material/menu_anchor.dart] Add animations to MenuAnchor. (flutter/flutter#176494) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 8e09f8a82251 to 174db42b7300 (6 revisions) (flutter/flutter#181627) 2026-01-28 31859944+LongCatIsLooong@users.noreply.github.com Send statusBarTouch events via dedicated messages (flutter/flutter#179643) 2026-01-28 git@reb0.org test: Improve DropdownMenuFormField tests (flutter/flutter#181369) 2026-01-28 evanwall@buffalo.edu Account for vec3 padding in Metal (flutter/flutter#181563) 2026-01-28 bkonyi@google.com [ Tool / Engine ] Cleanup x86 references (flutter/flutter#181152) 2026-01-28 ybz975218925@gmail.com Fix the issue on macOS where, after a hot restart with multiple windows, unresponsive windows are left behind. (flutter/flutter#180287) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 675444e94bc9 to 8e09f8a82251 (7 revisions) (flutter/flutter#181606) 2026-01-28 engine-flutter-autoroll@skia.org Roll Packages from e37af11 to 1cb2148 (5 revisions) (flutter/flutter#181608) 2026-01-28 codefu@google.com fix: swap app and engine version in vk::ApplicationInfo (flutter/flutter#181432) 2026-01-28 30870216+gaaclarke@users.noreply.github.com Adds impeller backend to skia gold client (flutter/flutter#181503) 2026-01-28 mdebbar@google.com Remove chrome_and_driver dependency where it's not needed (flutter/flutter#178174) 2026-01-28 codefu@google.com chore: Windows_mokey basic_material_app_win__compile !bringup (flutter/flutter#180985) 2026-01-28 116356835+AbdeMohlbi@users.noreply.github.com Fix generating both `settings.gradle` and `settings.gradle.kts` for plugins (flutter/flutter#181592) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 6614f89de521 to 675444e94bc9 (3 revisions) (flutter/flutter#181587) 2026-01-28 104349824+huycozy@users.noreply.github.com Fix `todayBorder` todayBorder color is incorrectly overridden by `todayForegroundColor` in CalendarDatePicker (flutter/flutter#178792) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from 8f1695a4b328 to 6614f89de521 (2 revisions) (flutter/flutter#181583) 2026-01-28 34465683+rkishan516@users.noreply.github.com feat: add RoundedSuperellipseInputBorder (flutter/flutter#177220) 2026-01-28 engine-flutter-autoroll@skia.org Roll Dart SDK from 38e351498549 to f10dcbfca98f (2 revisions) (flutter/flutter#181582) 2026-01-28 engine-flutter-autoroll@skia.org Roll Skia from f424d58e37a3 to 8f1695a4b328 (6 revisions) (flutter/flutter#181577) 2026-01-28 116356835+AbdeMohlbi@users.noreply.github.com Remove unused code paths in `PlatformViewsController.java` (flutter/flutter#181393) 2026-01-28 34465683+rkishan516@users.noreply.github.com feat: add onEnd to AnimatedCrossFade (flutter/flutter#181455) 2026-01-28 1961493+harryterkelsen@users.noreply.github.com Don't pass bounds to saveLayer call when painting ImageFilter (flutter/flutter#181353) 2026-01-28 luanpotter27@gmail.com test: Clarify failure messages on gestures/debug_test.dart (flutter/flutter#181109) 2026-01-27 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from akraNGn2lw4T1msgZ... to adhoq9ouVRh0xzkm3... (flutter/flutter#181571) 2026-01-27 engine-flutter-autoroll@skia.org Roll Dart SDK from 4c7cb0a1d07d to 38e351498549 (4 revisions) (flutter/flutter#181570) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedPadding doesn't crash in 0x0 environment (flutter/flutter#181235) 2026-01-27 ahmedsameha1@gmail.com Make sure that an ImageFiltered doesn't crash at 0x0 environment (flutter/flutter#181067) 2026-01-27 magder@google.com Marks firebase_release_smoke_test to be unflaky (flutter/flutter#181308) 2026-01-27 kazbek.sultanov.doc@gmail.com Fix remove material import box decoration test (flutter/flutter#181253) 2026-01-27 engine-flutter-autoroll@skia.org Roll Skia from c2754838b077 to f424d58e37a3 (8 revisions) (flutter/flutter#181564) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedAlign doesn't crash in 0x0 environment (flutter/flutter#181361) 2026-01-27 ahmedsameha1@gmail.com Make sure that an ImageIcon doesn't crash in 0x0 environment (flutter/flutter#181099) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedContainer doesn't crash in 0x0 environment (flutter/flutter#181198) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedRotation doesn't crash in 0x0 environment (flutter/flutter#181486) 2026-01-27 ahmedsameha1@gmail.com Make sure that an AnimatedPositionedDirectional doesn't crash in 0x0 … (flutter/flutter#181451) 2026-01-27 jacksongardner@google.com Merge changelog for 3.38.8. (flutter/flutter#181558) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC bmparr@google.com,stuartmorgan@google.com on the revert to ensure that a human is aware of the problem. ...
feat: add onEnd to AnimatedCrossFade
fixes: #180682
Pre-launch Checklist
///).