Adds animateToItem to the CarouselController by Mairramer · Pull Request #162694 · flutter/flutter

Mairramer · 2025-02-04T21:18:24Z

Closes #161368
This PR adds the animateToItem method to the CarouselController, enabling smooth, index-based navigation for carousels with fixed or dynamically-sized items (via flexWeights).

teste.mov

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I read the Contributor Guide and followed the process outlined there for submitting PRs.
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I listed at least one issue that this PR fixes in the description above.
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flutter-dashboard · 2025-02-05T12:55:03Z

This pull request has been changed to a draft. The currently pending flutter-gold status will not be able to resolve until a new commit is pushed or the change is marked ready for review again.

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QuncCccccc

Thanks so much for adding this new feature! Overall this looks great. Just left some thoughts below:)

QuncCccccc · 2025-02-12T07:42:17Z

packages/flutter/lib/src/material/carousel.dart

+
+  double _getTargetOffset(_CarouselPosition position, int index, bool hasFlexWeights) {
+    if (!hasFlexWeights) {
+      return index * _carouselState!._itemExtent!;


Should we constrain the index to between [0, children.length - 1]?

Although it doesn't cause an error, it results in a large scroll before returning to the last valid position. So yes, we can constrain the index.

Yes, we might want to assert that the index is in range.

packages/flutter/lib/src/material/carousel.dart

QuncCccccc · 2025-02-13T23:04:03Z

packages/flutter/lib/src/material/carousel.dart

+    final int totalWeight = weights.reduce((int a, int b) => a + b);
+    final double dimension = position.viewportDimension;
+
+    final bool isLastItem = index == carouselState.widget.children.length - 1;


I actually think only controlling the last item is not enough. When consumeMaxWeight is false, the behavior animating to other items is still different than when consumeMaxWeight is true.

Screen.Recording.2025-02-13.at.2.58.44.PM.mov

I made a small change to the logic, but I feel like I missed something.

Piinks · 2025-02-14T17:00:21Z

packages/flutter/test/material/carousel_test.dart

+    expect(realOffset(), controller.offset);
+  });
+
+  testWidgets('CarouselView animateToItem with flexWeights', (WidgetTester tester) async {


There should be several variants of this test, with different flex weights and numbers of children.

I just submitted several tests to cover various scenarios. If there is any missing, I will send it.

Piinks

Hey @Mairramer thanks for sending another PR! Some questions I wonder on this, how does setting a shrinkOffset affect this? Does this work when itemSnapping is true?

packages/flutter/test/material/carousel_test.dart

Mairramer · 2025-02-14T18:08:33Z

Hey @Mairramer thanks for sending another PR! Some questions I wonder on this, how does setting a shrinkOffset affect this? Does this work when itemSnapping is true?

Yes, works with itemSnapping.
About shrinkOffset I may have to adjust it, but I believe we won't have a problem (I'm trying to imagine some use cases).

QuncCccccc · 2025-02-19T18:48:00Z

packages/flutter/lib/src/material/carousel.dart

+    }
+
+    final bool hasFlexWeights = _carouselState!._flexWeights?.isNotEmpty ?? false;
+    index = index.clamp(0, _carouselState!.widget.children.length - 1);


NICE! Thanks!

packages/flutter/lib/src/material/carousel.dart

…oller

QuncCccccc

LGTM:) Thanks for adding the new feature!

packages/flutter/lib/src/material/carousel.dart

…oller

Piinks

This also LGTM, thank you!

…#162694)

flutter/flutter@2578d97...321fbc0 2025-03-06 [email protected] Roll Skia from fefecd49e03a to ccd8cc23aa94 (1 revision) (flutter/flutter#164712) 2025-03-06 [email protected] [web] Detect scrollable semantics nodes more reliably (flutter/flutter#164491) 2025-03-06 [email protected] [windows] wire the focus request and the focus events through the Windows platform (flutter/flutter#164296) 2025-03-06 [email protected] Roll Skia from 02897747c7d5 to fefecd49e03a (1 revision) (flutter/flutter#164701) 2025-03-06 [email protected] Roll Skia from e315b0ab7c84 to 02897747c7d5 (1 revision) (flutter/flutter#164677) 2025-03-06 [email protected] Roll Skia from 0c3880f94970 to e315b0ab7c84 (1 revision) (flutter/flutter#164669) 2025-03-06 [email protected] [Impeller] use device private on non-iOS devices. (flutter/flutter#164601) 2025-03-05 [email protected] Roll Skia from 43294a662fd0 to 0c3880f94970 (1 revision) (flutter/flutter#164661) 2025-03-05 [email protected] Add a workflow (only triggered from rest events) for hasing experiment (flutter/flutter#164657) 2025-03-05 [email protected] Roll Skia from 4cf9f0b77d41 to 43294a662fd0 (4 revisions) (flutter/flutter#164649) 2025-03-05 [email protected] Adds animateToItem to the CarouselController (flutter/flutter#162694) 2025-03-05 [email protected] Cleanup content context (flutter/flutter#164229) 2025-03-05 [email protected] Fix: Update CupertinoSheetRoute transition rounded corner (flutter/flutter#163700) 2025-03-05 [email protected] [Impeller] fix macOS managed memory. (flutter/flutter#164635) 2025-03-05 [email protected] [skwasm] Clear font collection cache when font is loaded manually. (flutter/flutter#164588) 2025-03-05 [email protected] Fix race condition causing crash when interacting with an animating scrollable (flutter/flutter#164392) 2025-03-05 [email protected] Use dwds 24.3.6 and pass uri for the reload scripts path to FrontendServerDdcLibraryBundleProvider (flutter/flutter#164582) 2025-03-05 [email protected] Roll Packages from 9e4684e to abba683 (8 revisions) (flutter/flutter#164630) 2025-03-05 [email protected] Roll Skia from 7e4323f72c9d to 4cf9f0b77d41 (1 revision) (flutter/flutter#164622) 2025-03-05 [email protected] Fix to Linux_pixel_7pro integration_ui_keyboard_resize test flakiness (flutter/flutter#162308) 2025-03-05 [email protected] Roll Skia from 03a3f653d64e to 7e4323f72c9d (1 revision) (flutter/flutter#164599) 2025-03-05 [email protected] Implement `clipPath` Mutator for hcpp (flutter/flutter#164525) 2025-03-05 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[Impeller] use DeviceLocal textures for gifs on non-iOS devices. (#164573)" (flutter/flutter#164600) 2025-03-05 [email protected] [macos] prefer integrated GPU. (flutter/flutter#164569) 2025-03-05 [email protected] Enforce minSdk constraint for Android Flutter (flutter/flutter#164251) 2025-03-05 [email protected] Add `clipRSuperellipse`, and use them for dialogs (flutter/flutter#161111) 2025-03-05 [email protected] Roll Skia from 46705a22edc3 to 03a3f653d64e (1 revision) (flutter/flutter#164590) 2025-03-05 [email protected] when resetting FlutterPlatformViewsController, clear out some additional internal state to prevent it from carrying over across a Hot Restart (flutter/flutter#164456) 2025-03-05 [email protected] Roll Fuchsia Linux SDK from Rt6pxGFLVAJHduM0V... to fhm5z889sA5T1AQao... (flutter/flutter#164583) 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 [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

…#162694)

flutter/flutter@2578d97...321fbc0 2025-03-06 [email protected] Roll Skia from fefecd49e03a to ccd8cc23aa94 (1 revision) (flutter/flutter#164712) 2025-03-06 [email protected] [web] Detect scrollable semantics nodes more reliably (flutter/flutter#164491) 2025-03-06 [email protected] [windows] wire the focus request and the focus events through the Windows platform (flutter/flutter#164296) 2025-03-06 [email protected] Roll Skia from 02897747c7d5 to fefecd49e03a (1 revision) (flutter/flutter#164701) 2025-03-06 [email protected] Roll Skia from e315b0ab7c84 to 02897747c7d5 (1 revision) (flutter/flutter#164677) 2025-03-06 [email protected] Roll Skia from 0c3880f94970 to e315b0ab7c84 (1 revision) (flutter/flutter#164669) 2025-03-06 [email protected] [Impeller] use device private on non-iOS devices. (flutter/flutter#164601) 2025-03-05 [email protected] Roll Skia from 43294a662fd0 to 0c3880f94970 (1 revision) (flutter/flutter#164661) 2025-03-05 [email protected] Add a workflow (only triggered from rest events) for hasing experiment (flutter/flutter#164657) 2025-03-05 [email protected] Roll Skia from 4cf9f0b77d41 to 43294a662fd0 (4 revisions) (flutter/flutter#164649) 2025-03-05 [email protected] Adds animateToItem to the CarouselController (flutter/flutter#162694) 2025-03-05 [email protected] Cleanup content context (flutter/flutter#164229) 2025-03-05 [email protected] Fix: Update CupertinoSheetRoute transition rounded corner (flutter/flutter#163700) 2025-03-05 [email protected] [Impeller] fix macOS managed memory. (flutter/flutter#164635) 2025-03-05 [email protected] [skwasm] Clear font collection cache when font is loaded manually. (flutter/flutter#164588) 2025-03-05 [email protected] Fix race condition causing crash when interacting with an animating scrollable (flutter/flutter#164392) 2025-03-05 [email protected] Use dwds 24.3.6 and pass uri for the reload scripts path to FrontendServerDdcLibraryBundleProvider (flutter/flutter#164582) 2025-03-05 [email protected] Roll Packages from 9e4684e to abba683 (8 revisions) (flutter/flutter#164630) 2025-03-05 [email protected] Roll Skia from 7e4323f72c9d to 4cf9f0b77d41 (1 revision) (flutter/flutter#164622) 2025-03-05 [email protected] Fix to Linux_pixel_7pro integration_ui_keyboard_resize test flakiness (flutter/flutter#162308) 2025-03-05 [email protected] Roll Skia from 03a3f653d64e to 7e4323f72c9d (1 revision) (flutter/flutter#164599) 2025-03-05 [email protected] Implement `clipPath` Mutator for hcpp (flutter/flutter#164525) 2025-03-05 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[Impeller] use DeviceLocal textures for gifs on non-iOS devices. (#164573)" (flutter/flutter#164600) 2025-03-05 [email protected] [macos] prefer integrated GPU. (flutter/flutter#164569) 2025-03-05 [email protected] Enforce minSdk constraint for Android Flutter (flutter/flutter#164251) 2025-03-05 [email protected] Add `clipRSuperellipse`, and use them for dialogs (flutter/flutter#161111) 2025-03-05 [email protected] Roll Skia from 46705a22edc3 to 03a3f653d64e (1 revision) (flutter/flutter#164590) 2025-03-05 [email protected] when resetting FlutterPlatformViewsController, clear out some additional internal state to prevent it from carrying over across a Hot Restart (flutter/flutter#164456) 2025-03-05 [email protected] Roll Fuchsia Linux SDK from Rt6pxGFLVAJHduM0V... to fhm5z889sA5T1AQao... (flutter/flutter#164583) 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 [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

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Mairramer marked this pull request as draft February 5, 2025 12:50

Mairramer marked this pull request as ready for review February 5, 2025 12:55

Piinks requested review from Piinks and QuncCccccc February 5, 2025 19:22

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Mairramer added 6 commits February 14, 2025 08:32

feat: adds animateToItem to the CarouselController class

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Mairramer force-pushed the feat/add-animateToItem-into-carousel-controller branch from 4c4e849 to 3f923d1 Compare February 14, 2025 11:32

improve logic

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test: addes a lot of tests

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small fixes

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✨ Implement animateToItem Method in CarouselController to Animate to Specific Item #161472

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Mairramer commented Feb 4, 2025 •

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