Fix input mirroring in platform views when system language is RTL, and support is set in manifest. by gmackall · Pull Request #183472 · flutter/flutter

gmackall · 2026-03-10T21:53:53Z

We use a FrameLayout to wrap platform views. We construct new FrameLayout.LayoutParams and set them on the frame layout (here, and a couple of other places). Because we don't specify a gravity, it defaults to UNSPECIFIED_GRAVITY, which is Gravity.TOP | Gravity.START. When a developer indicates that their app supports RTL (right-to-left) layouts (e.g. arabic), and the system language is set to one with an RTL layout, START becomes right https://developer.android.com/reference/android/view/Gravity#getAbsoluteGravity(int,%20int), and the view ends up thinking it is positioned relative to the right of the screen, even though we are controlling the drawing and putting it on the left.

Because we are handling the drawing, and all that matters is that flutter knows where the view is, we can just statically set the horizontal gravity to be left. Then flutter knows where to find the view and deliver the tap to it, whether we are in an RTL or LTR layout.

…fileiscalled

gmackall · 2026-03-10T22:07:47Z

          final ViewGroup.LayoutParams viewWrapperLayoutParams = viewWrapper.getLayoutParams();
          viewWrapperLayoutParams.width = physicalWidth;
          viewWrapperLayoutParams.height = physicalHeight;
+          if (viewWrapperLayoutParams instanceof FrameLayout.LayoutParams) {


This is kind of weird: the call to FrameLayout.getLayoutParams above returns a ViewGroup.LayoutParams, not a FrameLayout.LayoutParams. Then we immediately call our own setLayoutParams implementation:
https://github.com/flutter/flutter/blob/master/engine/src/flutter/shell/platform/android/io/flutter/plugin/platform/PlatformViewWrapper.java#L87
which takes a FrameLayout.LayoutParams, so we are always doing this cast which I am checking for. I could alternatively put this in the setLayoutParams method, but I'd prefer to keep the layout parameter configuration here in one place. But I acknowledge it looks weird... in my defense it's weird that android gives back a ViewGroup.LayoutParams in the first place...

gmackall · 2026-03-10T22:21:27Z

+    await flutterDriver.close();
+  });
+
+  test(


Neither taps delivered by flutterDriver or the nativeDriver extension repro the issue. Instead, this test requests the location of the blue box via flutter driver, and also requests pixel information, to calculate the location of the box and deliver a tab via adb to those physical coordinates.

gemini-code-assist

Code Review

This pull request fixes an issue with input mirroring for platform views in RTL layouts by explicitly setting the gravity of FrameLayout.LayoutParams to Gravity.LEFT | Gravity.TOP. This prevents the default Gravity.START from being misinterpreted in RTL contexts. The changes are applied consistently across FlutterMutatorView, PlatformViewsController, and PlatformViewsController2. A new integration test is also added to verify the fix. The fix appears correct and well-tested. However, I found a compilation error in the new test application code that needs to be addressed.

gmackall · 2026-03-10T22:50:00Z

/gemini review

gemini-code-assist

Code Review

This pull request addresses an input mirroring issue on platform views in RTL layouts. The changes involve explicitly setting the gravity to Gravity.LEFT | Gravity.TOP for FrameLayout.LayoutParams in FlutterMutatorView, PlatformViewsController, and PlatformViewsController2. This ensures platform views are positioned correctly regardless of layout direction. Additionally, an integration test has been added to verify the fix, which required enabling RTL support in the test application's manifest.

gemini-code-assist

Code Review

This pull request effectively addresses an input mirroring issue on platform views in RTL layouts by explicitly setting the layout gravity to Gravity.LEFT | Gravity.TOP. The change is well-supported by a new integration test that accurately reproduces and verifies the fix. My only suggestion is to consider deduplicating the new gravity value to improve code maintainability.

…is RTL, and support is set in manifest. (flutter/flutter#183472)

flutter/flutter@3f400d7...9e36adb 2026-03-12 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from QD887D4OanteB7UKM... to jJbpv4J_tjW-wuKDq... (flutter/flutter#183584) 2026-03-12 matt.kosarek@canonical.com Adding the SatelliteWindowController interface to `_window.dart` (flutter/flutter#182903) 2026-03-12 engine-flutter-autoroll@skia.org Roll Skia from 0cab3e4ee34b to 46f41493ebf4 (17 revisions) (flutter/flutter#183553) 2026-03-12 engine-flutter-autoroll@skia.org Roll Dart SDK from 8531f7c2bdae to 59be21f25f2d (4 revisions) (flutter/flutter#183547) 2026-03-12 koji.wakamiya@gmail.com [ios][engine] Fix keyboard flicker when switching text fields (flutter/flutter#182661) 2026-03-11 34871572+gmackall@users.noreply.github.com Rename hcpp opt in flag to `enable-hcpp` (flutter/flutter#183151) 2026-03-11 137456488+flutter-pub-roller-bot@users.noreply.github.com Roll pub packages (flutter/flutter#183541) 2026-03-11 97480502+b-luk@users.noreply.github.com Re-enable gpu_test.dart for opengles, but disable specific tests in the file (flutter/flutter#183531) 2026-03-11 jacksongardner@google.com Use CLA-approved email and username for github workflow commits. (flutter/flutter#183540) 2026-03-11 okorohelijah@google.com [integration_test]UIScene Migration (flutter/flutter#182631) 2026-03-11 git@reb0.org ci: Run orchestrator for windows_arm_host_engine on Linux (flutter/flutter#181075) 2026-03-11 mdebbar@google.com [web] Prevent Firefox auto-updates (flutter/flutter#183330) 2026-03-11 koji.wakamiya@gmail.com Add scrollCacheExtent to PageView (flutter/flutter#180411) 2026-03-11 danny@tuppeny.com Remove redundant VS Code code/tests (flutter/flutter#183506) 2026-03-11 danny@tuppeny.com Roll pub packages (flutter/flutter#183527) 2026-03-11 34871572+gmackall@users.noreply.github.com Reapply "Make HCPP upgrading work for vd/tlhc (#181024)" (#183310) (flutter/flutter#183360) 2026-03-11 victorsanniay@gmail.com Add awaits to dev/ callsites (flutter/flutter#183479) 2026-03-11 stuartmorgan@google.com Standardize review timeline guidance (flutter/flutter#183465) 2026-03-11 chingjun@google.com Rename ExecutionModelToString to ExecutionModelToStringName. (flutter/flutter#183461) 2026-03-11 34871572+gmackall@users.noreply.github.com Fix input mirroring in platform views when system language is RTL, and support is set in manifest. (flutter/flutter#183472) 2026-03-11 engine-flutter-autoroll@skia.org Roll Packages from ee460d6 to ecace66 (10 revisions) (flutter/flutter#183517) 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 stuartmorgan@google.com 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

…r#11233) flutter/flutter@3f400d7...9e36adb 2026-03-12 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from QD887D4OanteB7UKM... to jJbpv4J_tjW-wuKDq... (flutter/flutter#183584) 2026-03-12 matt.kosarek@canonical.com Adding the SatelliteWindowController interface to `_window.dart` (flutter/flutter#182903) 2026-03-12 engine-flutter-autoroll@skia.org Roll Skia from 0cab3e4ee34b to 46f41493ebf4 (17 revisions) (flutter/flutter#183553) 2026-03-12 engine-flutter-autoroll@skia.org Roll Dart SDK from 8531f7c2bdae to 59be21f25f2d (4 revisions) (flutter/flutter#183547) 2026-03-12 koji.wakamiya@gmail.com [ios][engine] Fix keyboard flicker when switching text fields (flutter/flutter#182661) 2026-03-11 34871572+gmackall@users.noreply.github.com Rename hcpp opt in flag to `enable-hcpp` (flutter/flutter#183151) 2026-03-11 137456488+flutter-pub-roller-bot@users.noreply.github.com Roll pub packages (flutter/flutter#183541) 2026-03-11 97480502+b-luk@users.noreply.github.com Re-enable gpu_test.dart for opengles, but disable specific tests in the file (flutter/flutter#183531) 2026-03-11 jacksongardner@google.com Use CLA-approved email and username for github workflow commits. (flutter/flutter#183540) 2026-03-11 okorohelijah@google.com [integration_test]UIScene Migration (flutter/flutter#182631) 2026-03-11 git@reb0.org ci: Run orchestrator for windows_arm_host_engine on Linux (flutter/flutter#181075) 2026-03-11 mdebbar@google.com [web] Prevent Firefox auto-updates (flutter/flutter#183330) 2026-03-11 koji.wakamiya@gmail.com Add scrollCacheExtent to PageView (flutter/flutter#180411) 2026-03-11 danny@tuppeny.com Remove redundant VS Code code/tests (flutter/flutter#183506) 2026-03-11 danny@tuppeny.com Roll pub packages (flutter/flutter#183527) 2026-03-11 34871572+gmackall@users.noreply.github.com Reapply "Make HCPP upgrading work for vd/tlhc (#181024)" (#183310) (flutter/flutter#183360) 2026-03-11 victorsanniay@gmail.com Add awaits to dev/ callsites (flutter/flutter#183479) 2026-03-11 stuartmorgan@google.com Standardize review timeline guidance (flutter/flutter#183465) 2026-03-11 chingjun@google.com Rename ExecutionModelToString to ExecutionModelToStringName. (flutter/flutter#183461) 2026-03-11 34871572+gmackall@users.noreply.github.com Fix input mirroring in platform views when system language is RTL, and support is set in manifest. (flutter/flutter#183472) 2026-03-11 engine-flutter-autoroll@skia.org Roll Packages from ee460d6 to ecace66 (10 revisions) (flutter/flutter#183517) 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 stuartmorgan@google.com 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

…d support is set in manifest. (flutter#183472) Fixes flutter#182823 We use a [`FrameLayout`](https://developer.android.com/reference/android/widget/FrameLayout) to [wrap platform views](https://github.com/flutter/flutter/blob/master/engine/src/flutter/shell/platform/android/io/flutter/embedding/engine/mutatorsstack/FlutterMutatorView.java#L30). We construct new `FrameLayout.LayoutParams` and set them on the frame layout ([here](https://github.com/flutter/flutter/blob/758463261fabe1b37f2a4752bfc44a57e10c79b7/engine/src/flutter/shell/platform/android/io/flutter/embedding/engine/mutatorsstack/FlutterMutatorView.java#L107), and a couple of other places). Because we don't specify a gravity, it defaults to [UNSPECIFIED_GRAVITY](https://developer.android.com/reference/android/widget/FrameLayout.LayoutParams#gravity), which is `Gravity.TOP | Gravity.START`. When a developer indicates that their app supports RTL (right-to-left) layouts (e.g. arabic), and the system language is set to one with an RTL layout, START becomes left https://developer.android.com/reference/android/view/Gravity#getAbsoluteGravity(int,%20int), and the view ends up thinking it is positioned relative to the right of the screen, even though we are controlling the drawing and putting it on the left. Because we are handling the drawing, and all that matters is that flutter knows where the view is, we can just statically set the horizontal gravity to be left. Then flutter knows where to find the view and deliver the tap to it, whether we are in an RTL or LTR layout. --------- Co-authored-by: Gray Mackall <mackall@google.com>

…r#11233) flutter/flutter@3f400d7...9e36adb 2026-03-12 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from QD887D4OanteB7UKM... to jJbpv4J_tjW-wuKDq... (flutter/flutter#183584) 2026-03-12 matt.kosarek@canonical.com Adding the SatelliteWindowController interface to `_window.dart` (flutter/flutter#182903) 2026-03-12 engine-flutter-autoroll@skia.org Roll Skia from 0cab3e4ee34b to 46f41493ebf4 (17 revisions) (flutter/flutter#183553) 2026-03-12 engine-flutter-autoroll@skia.org Roll Dart SDK from 8531f7c2bdae to 59be21f25f2d (4 revisions) (flutter/flutter#183547) 2026-03-12 koji.wakamiya@gmail.com [ios][engine] Fix keyboard flicker when switching text fields (flutter/flutter#182661) 2026-03-11 34871572+gmackall@users.noreply.github.com Rename hcpp opt in flag to `enable-hcpp` (flutter/flutter#183151) 2026-03-11 137456488+flutter-pub-roller-bot@users.noreply.github.com Roll pub packages (flutter/flutter#183541) 2026-03-11 97480502+b-luk@users.noreply.github.com Re-enable gpu_test.dart for opengles, but disable specific tests in the file (flutter/flutter#183531) 2026-03-11 jacksongardner@google.com Use CLA-approved email and username for github workflow commits. (flutter/flutter#183540) 2026-03-11 okorohelijah@google.com [integration_test]UIScene Migration (flutter/flutter#182631) 2026-03-11 git@reb0.org ci: Run orchestrator for windows_arm_host_engine on Linux (flutter/flutter#181075) 2026-03-11 mdebbar@google.com [web] Prevent Firefox auto-updates (flutter/flutter#183330) 2026-03-11 koji.wakamiya@gmail.com Add scrollCacheExtent to PageView (flutter/flutter#180411) 2026-03-11 danny@tuppeny.com Remove redundant VS Code code/tests (flutter/flutter#183506) 2026-03-11 danny@tuppeny.com Roll pub packages (flutter/flutter#183527) 2026-03-11 34871572+gmackall@users.noreply.github.com Reapply "Make HCPP upgrading work for vd/tlhc (#181024)" (#183310) (flutter/flutter#183360) 2026-03-11 victorsanniay@gmail.com Add awaits to dev/ callsites (flutter/flutter#183479) 2026-03-11 stuartmorgan@google.com Standardize review timeline guidance (flutter/flutter#183465) 2026-03-11 chingjun@google.com Rename ExecutionModelToString to ExecutionModelToStringName. (flutter/flutter#183461) 2026-03-11 34871572+gmackall@users.noreply.github.com Fix input mirroring in platform views when system language is RTL, and support is set in manifest. (flutter/flutter#183472) 2026-03-11 engine-flutter-autoroll@skia.org Roll Packages from ee460d6 to ecace66 (10 revisions) (flutter/flutter#183517) 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 stuartmorgan@google.com 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

mackall-work added 2 commits March 10, 2026 14:44

fix+test, missing run configuration in run_android_engine_whatevrthis…

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…fileiscalled

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github-actions Bot added platform-android Android applications specifically engine flutter/engine related. See also e: labels. team-android Owned by Android platform team labels Mar 10, 2026

gmackall commented Mar 10, 2026

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mackall-work and others added 2 commits March 10, 2026 15:17

set manifest value

1cbda1a

Merge branch 'master' into fix_rtl_pv_input_mirror

69f2a77

gmackall marked this pull request as ready for review March 10, 2026 22:19

gmackall requested a review from a team as a code owner March 10, 2026 22:19

gmackall commented Mar 10, 2026

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Comment thread dev/integration_tests/android_engine_test/lib/hcpp/rtl_mirror_main.dart

thanks gemini

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Comment thread ...e/src/flutter/shell/platform/android/io/flutter/plugin/platform/PlatformViewsController.java

forgot license header, classic

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reidbaker approved these changes Mar 11, 2026

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Merged via the queue into flutter:master with commit fec7a38 Mar 11, 2026
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[Android] PlatformView pointer events (tap & drag) are horizontally mirrored in RTL mode #182823

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fec7a38d7 Fix input mirroring in platform views when system language …

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…is RTL, and support is set in manifest. (flutter/flutter#183472)

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Roll Flutter from 3f400d7c69e1 to 9f20e5d9bbd3 (20 revisions) flutter/packages#11232

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fec7a38d7 Fix input mirroring in platform views when system language …

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…is RTL, and support is set in manifest. (flutter/flutter#183472)

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Roll Flutter from 3f400d7c69e1 to 9e36adba5069 (21 revisions) flutter/packages#11233

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fec7a38d7 Fix input mirroring in platform views when system language …

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…is RTL, and support is set in manifest. (flutter/flutter#183472)

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Roll Flutter from 3f400d7c69e1 to bd3eccc13d57 (22 revisions) flutter/packages#11235

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fec7a38d7 Fix input mirroring in platform views when system language …

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…is RTL, and support is set in manifest. (flutter/flutter#183472)

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Roll Flutter from 3f400d7c69e1 to 752f6135a249 (23 revisions) flutter/packages#11238

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Fix input mirroring in platform views when system language is RTL, and support is set in manifest.#183472

Fix input mirroring in platform views when system language is RTL, and support is set in manifest.#183472
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