Fix TabBar.image does not render at initialIndex for the first time by huycozy · Pull Request #179616 · flutter/flutter

huycozy · 2025-12-09T10:09:30Z

Fix Tabbar.image does not render at initialIndex for the first time #59143
The investigation is at Tabbar.image does not render at initialIndex for the first time #59143 (comment)
Describe the fix:
- Make _IndicatorPainter listen to both the controller animation and a new painter notifier triggered when the indicator image finishes fetching.
- Added some regression tests

Demo

before	after
before.mov	after.mov

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dkwingsmt

LGTM. Thank you so much for the investigation and fix!

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

auto-submit · 2026-01-07T08:00:33Z

autosubmit label was removed for flutter/flutter/179616, because The base commit of the PR is older than 7 days and can not be merged. Please merge the latest changes from the main into this branch and resubmit the PR.

Signed-off-by: huycozy <[email protected]>

…t time (flutter/flutter#179616)

Roll Flutter from 13b2b91 to 01d37bc (74 revisions) flutter/flutter@13b2b91...01d37bc 2026-01-07 [email protected] Replace Hybrid Composition wiki page with dev-facing content (flutter/flutter#180642) 2026-01-07 [email protected] Improve code quality in `FlutterActivityTest.java` (flutter/flutter#180585) 2026-01-07 [email protected] Roll Dart SDK to 3.11.0-296.1.beta (flutter/flutter#180633) 2026-01-07 [email protected] Bump target Windows version to 10 (flutter/flutter#180624) 2026-01-07 [email protected] Run hook_user_defines and link_hook integration tests on CI (flutter/flutter#180622) 2026-01-07 [email protected] Fix division by zero in RenderTable intrinsic size methods (flutter/flutter#178217) 2026-01-07 [email protected] Remove more `requires 24` anotations (flutter/flutter#180116) 2026-01-07 [email protected] Roll Skia from 3971dbb85d45 to c5359a4d720e (1 revision) (flutter/flutter#180631) 2026-01-07 [email protected] Fix TabBar.image does not render at initialIndex for the first time (flutter/flutter#179616) 2026-01-07 [email protected] Roll Skia from 1e7ad625f6f7 to 3971dbb85d45 (3 revisions) (flutter/flutter#180627) 2026-01-07 [email protected] Unpin DDS (flutter/flutter#180571) 2026-01-07 [email protected] Fix DropdownMenuEntry.style not resolved when entry is highlighted (flutter/flutter#178873) 2026-01-07 [email protected] Remove unnecessary `@RequiresApi24` annotations from FlutterFragment methods (flutter/flutter#180117) 2026-01-07 [email protected] Roll Skia from 7fc63228056b to 1e7ad625f6f7 (1 revision) (flutter/flutter#180616) 2026-01-07 [email protected] Roll Fuchsia Linux SDK from QfR2ZFZ5kGTD3raO3... to dTvN_JVSCfGFRasvH... (flutter/flutter#180612) 2026-01-07 [email protected] [ Widget Preview ] Add support for `dart:ffi` imports (flutter/flutter#180586) 2026-01-07 [email protected] Roll Skia from eec90000a899 to 7fc63228056b (2 revisions) (flutter/flutter#180608) 2026-01-07 [email protected] Add --web-define flag for template variable injection in Flutter web builds (flutter/flutter#175805) 2026-01-07 [email protected] docs(engine): update rbe notes (flutter/flutter#180599) 2026-01-06 [email protected] Roll Skia from b6249496c230 to eec90000a899 (3 revisions) (flutter/flutter#180602) 2026-01-06 [email protected] Forward proxy 404 responses to client (flutter/flutter#179858) 2026-01-06 [email protected] Roll Dart SDK from 40a8c6188f7f to d2e3ce177270 (1 revision) (flutter/flutter#180598) 2026-01-06 [email protected] Restore CLI precedence for web headers and HTTPS over web_dev_config.yaml (flutter/flutter#179639) 2026-01-06 [email protected] Roll Skia from f5d9da13d56d to b6249496c230 (1 revision) (flutter/flutter#180596) 2026-01-06 [email protected] Enable misc leak tracking (flutter/flutter#176992) 2026-01-06 [email protected] [hooks] Don't require NDK for Android targets (flutter/flutter#180594) 2026-01-06 [email protected] [skia] Disable legacy non-const SkData APIs (flutter/flutter#179684) 2026-01-06 [email protected] Fix/ios share context menu (flutter/flutter#176199) 2026-01-06 [email protected] Roll Skia from b970aeffa66f to f5d9da13d56d (5 revisions) (flutter/flutter#180588) 2026-01-06 [email protected] Manually bump dependencies (flutter/flutter#180509) 2026-01-06 [email protected] Roll Dart SDK from 8150be8a0e48 to 40a8c6188f7f (2 revisions) (flutter/flutter#180582) 2026-01-06 [email protected] Roll Packages from 12eb764 to d3f860d (2 revisions) (flutter/flutter#180581) 2026-01-06 [email protected] Roll Fuchsia Test Scripts from MHF-UAfO6sVKqSEYk... to nR2ESa1Gd8yPcWo06... (flutter/flutter#180578) 2026-01-06 [email protected] Add tooltip support to PlatformMenuItem and PlatformMenu. (flutter/flutter#180069) 2026-01-06 [email protected] Add DropdownMenuFormField.errorBuilder (flutter/flutter#179345) 2026-01-06 [email protected] Roll Skia from 1845397e11ba to b970aeffa66f (2 revisions) (flutter/flutter#180566) 2026-01-06 [email protected] Don't embed unreferenced assets (flutter/flutter#179251) 2026-01-06 [email protected] Improve documentation about ValueNotifier's behavior (flutter/flutter#179870) 2026-01-06 [email protected] Roll Skia from 904ba00331ca to 1845397e11ba (5 revisions) (flutter/flutter#180558) 2026-01-06 [email protected] Roll Dart SDK from 2fb9ad834c4d to 8150be8a0e48 (1 revision) (flutter/flutter#180557) 2026-01-06 [email protected] Roll Skia from 98c042dde68c to 904ba00331ca (3 revisions) (flutter/flutter#180550) 2026-01-06 [email protected] Roll Dart SDK from ba9f7f790966 to 2fb9ad834c4d (2 revisions) (flutter/flutter#180548) 2026-01-06 [email protected] Roll Fuchsia Linux SDK from ubBGcRaAKWKihQ4ac... to QfR2ZFZ5kGTD3raO3... (flutter/flutter#180547) 2026-01-06 [email protected] Make sure that a DraggableScrollableSheet doesn't crash in 0x0 enviro… (flutter/flutter#180433) 2026-01-06 [email protected] Make sure that a ColorFiltered doesn't crash 0x0 environment (flutter/flutter#180307) 2026-01-06 [email protected] Make sure that a FadeInImage doesn't crash in 0x0 environment (flutter/flutter#180495) ...

…t time (flutter/flutter#179616)

huycozy self-assigned this Dec 9, 2025

github-actions bot added framework flutter/packages/flutter repository. See also f: labels. f: material design flutter/packages/flutter/material repository. labels Dec 9, 2025

huycozy force-pushed the fix-Tabbar.image-does-not-render-at-initialIndex-for-the-first-time-59143 branch 2 times, most recently from f515361 to 2c87192 Compare December 9, 2025 11:45

huycozy marked this pull request as ready for review December 9, 2025 14:26

huycozy requested a review from goderbauer December 9, 2025 14:26

dkwingsmt requested review from dkwingsmt and removed request for goderbauer December 10, 2025 19:09

dkwingsmt approved these changes Jan 6, 2026

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Fix TabBar.image does not render at initialIndex for the first time

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Signed-off-by: huycozy <[email protected]>

fixup: add documentation

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Signed-off-by: huycozy <[email protected]>

huycozy force-pushed the fix-Tabbar.image-does-not-render-at-initialIndex-for-the-first-time-59143 branch from b4529e0 to 370bf42 Compare January 7, 2026 09:53

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Merged via the queue into flutter:master with commit af63b5e Jan 7, 2026
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Fix TabBar.image does not render at initialIndex for the first time#179616

Fix TabBar.image does not render at initialIndex for the first time#179616
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