[camera] Convert iOS event channel to Pigeon by stuartmorgan-g · Pull Request #11109 · flutter/packages

stuartmorgan-g · 2026-02-24T16:57:12Z

Replaces direct event channel usage with type-safe Pigeon event channels now that the plugin has been migrated to Swift (Pigeon doesn't have event channel support in the Obj-C generator, so this had been blocked).

Also includes opportunistic cleanup of conditional import of camera_avfoundation_objc, since I noticed it in the files I was working in; this is dead code now that the Swift migration is complete, because the camera_avfoundation_objc no longer exists.

Fixes flutter/flutter#182542

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The pull request successfully migrates the iOS event channel to use Pigeon for type-safe image streaming. This change improves code quality by leveraging Pigeon's type safety, which was previously blocked due to Swift migration. The removal of camera_avfoundation_objc imports and related test files indicates a good cleanup of dead code. The changes to CHANGELOG.md and pubspec.yaml are also appropriate. I've identified a few areas for improvement regarding mock values and consistency in test assertions.

packages/camera/camera_avfoundation/example/ios/Runner.xcodeproj/project.pbxproj

packages/camera/camera_avfoundation/example/ios/RunnerTests/Mocks/MockCaptureDevice.swift

packages/camera/camera_avfoundation/example/ios/RunnerTests/StreamingTests.swift

.../camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift

packages/camera/camera_avfoundation/pigeons/messages.dart

packages/camera/camera_avfoundation/pubspec.yaml

packages/camera/camera_avfoundation/test/type_conversion_test.dart

gemini-code-assist · 2026-02-24T17:00:12Z

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stuartmorgan-g · 2026-02-24T16:58:06Z

packages/camera/camera_avfoundation/example/ios/RunnerTests/Mocks/MockCaptureDevice.swift

  }

-  var lensAperture: Float { 0 }
+  var lensAperture: Float { 1.8 }


I changed these to more realistic values to make the updated tests easier to write (see comment there).

stuartmorgan-g · 2026-02-24T16:58:54Z

...camera/camera_avfoundation/example/ios/RunnerTests/Mocks/MockDeviceOrientationProvider.swift

 // found in the LICENSE file.

-@testable import camera_avfoundation
+import UIKit


I'm not sure why we were getting away without this before; it should be here because of the UIDeviceOrientation usage, and it caused compile issues for me.

stuartmorgan-g · 2026-02-24T17:01:20Z

packages/camera/camera_avfoundation/example/ios/RunnerTests/StreamingTests.swift

+      XCTAssertGreaterThan(imageBuffer.formatCode, 0)
+      XCTAssertGreaterThan(imageBuffer.lensAperture, 0)
+      XCTAssertGreaterThan(imageBuffer.sensorExposureTimeNanoseconds, 0)
+      XCTAssertGreaterThan(imageBuffer.sensorSensitivity, 0)


I did these as GreaterThan because it was the easiest upgrade from the very loose is NSNumber tests that was not worthless (checking the types would be pointless now that it's structured data). Ideally we would check that the correct values come through, but the way the mocks are set up with hard-coded values, it would require non-trivial restructuring of the tests (to allow passing in values from here) to do anything other than check magic numbers from another file, and I didn't want to make significant test changes with the implementation change.

stuartmorgan-g · 2026-02-24T17:02:19Z

.../camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift

+      ImageDataStreamStreamHandler.register(with: messenger, streamHandler: imageStreamHandler)
+      self.imageStreamHandler = imageStreamHandler
+      self.captureSessionQueue.async { [weak self] in
+        if let self = self {


Slightly restructured here to avoid having two different completion codepaths.

stuartmorgan-g · 2026-02-24T17:03:40Z

.../camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift

-    self.imageStreamHandler = imageStreamHandler
-    threadSafeEventChannel.setStreamHandler(imageStreamHandler) { [weak self] in
-      guard let strongSelf = self else {
+    ensureToRunOnMainQueue { [weak self] in


This replaces the entire thread-safe event channel subclass we used to have. This was the only thing we were doing that needed to be on the main thread that wasn't already dispatched to the main thread, so rewriting the whole thread safe class structure for Pigeon seemed like overkill.

stuartmorgan-g · 2026-02-24T17:06:18Z

packages/camera/camera_avfoundation/lib/src/type_conversion.dart


-ImageFormatGroup _imageFormatGroupFromPlatformData(dynamic data) {
+ImageFormatGroup _imageFormatGroupFromPlatformImageFormat(int data) {
  switch (data) {


Normally I would make the enum part of the Pigeon definition, but since we are also passing the raw code through the public API anyway I didn't bother. I could do both though if anyone prefers that; it would have the slight advantage we wouldn't need magic numbers in this file (even though they would still be passed out publicly).

.../camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift

packages/camera/camera_avfoundation/pigeons/messages.dart

…ges#11109)

flutter/packages@acd9adb...e1d0169 2026-02-26 [email protected] [rfw] Remove outdated info from README (flutter/packages#11123) 2026-02-25 [email protected] [local_auth] Federate READMEs (flutter/packages#11112) 2026-02-25 [email protected] [google_sign_in] Remove usersCleartextTraffic (flutter/packages#11121) 2026-02-25 [email protected] Tidy up some contributing text, and note tools needed for formatting. (flutter/packages#11113) 2026-02-25 [email protected] [video_player_android] Remove usesCleartextTraffic (flutter/packages#11075) 2026-02-25 [email protected] Adjust the version/changelog checklist entries (flutter/packages#11120) 2026-02-25 [email protected] [camera] Convert iOS event channel to Pigeon (flutter/packages#11109) 2026-02-25 8490712[email protected] [camera] add video stabilization (flutter/packages#7108) 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-flutter-autoroll Please CC [email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Flutter: 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#182946) flutter/packages@acd9adb...e1d0169 2026-02-26 [email protected] [rfw] Remove outdated info from README (flutter/packages#11123) 2026-02-25 [email protected] [local_auth] Federate READMEs (flutter/packages#11112) 2026-02-25 [email protected] [google_sign_in] Remove usersCleartextTraffic (flutter/packages#11121) 2026-02-25 [email protected] Tidy up some contributing text, and note tools needed for formatting. (flutter/packages#11113) 2026-02-25 [email protected] [video_player_android] Remove usesCleartextTraffic (flutter/packages#11075) 2026-02-25 [email protected] Adjust the version/changelog checklist entries (flutter/packages#11120) 2026-02-25 [email protected] [camera] Convert iOS event channel to Pigeon (flutter/packages#11109) 2026-02-25 8490712[email protected] [camera] add video stabilization (flutter/packages#7108) 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-flutter-autoroll Please CC [email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Flutter: 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

stuartmorgan-g added 3 commits February 24, 2026 11:47

Update event channel to use Pigeon.

979c742

Remove obsolete imports

a62a876

Version bump

b63856d

stuartmorgan-g requested review from LouiseHsu and hellohuanlin as code owners February 24, 2026 16:57

github-actions bot added p: camera platform-ios platform-macos labels Feb 24, 2026

gemini-code-assist bot reviewed Feb 24, 2026

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stuartmorgan-g commented Feb 24, 2026

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Comma fix

af09e9b

hellohuanlin approved these changes Feb 24, 2026

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.../camera_avfoundation/ios/camera_avfoundation/Sources/camera_avfoundation/DefaultCamera.swift Outdated Show resolved Hide resolved

packages/camera/camera_avfoundation/pigeons/messages.dart Show resolved Hide resolved

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stuartmorgan-g added the autosubmit Merge PR when tree becomes green via auto submit App label Feb 25, 2026

auto-submit bot merged commit 7fe183f into flutter:main Feb 25, 2026
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engine-flutter-autoroll added a commit to engine-flutter-autoroll/flutter that referenced this pull request Feb 26, 2026

7fe183f96 [camera] Convert iOS event channel to Pigeon (flutter/packa…

8ec9893

…ges#11109)

engine-flutter-autoroll mentioned this pull request Feb 26, 2026

Roll Packages from acd9adbe4676 to e1d01695273f (8 revisions) flutter/flutter#182946

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stuartmorgan-g commented Feb 24, 2026

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