Add an onTapToFocus event

[ZayanKhan-12]

The problem

#590 wants to react to a tap on the camera area without giving up the camera's own gestures. A sibling overlay with an onPress swallows the touch, which kills tap-to-focus and pinch-to-zoom, and <Camera> doesn't accept children — so there was no way to have both.

The approach

Rather than opening the view up to children, this reports the tap. The gesture that already drives tap-to-focus now also emits onTapToFocus with the tap position, so an overlay can react to it while focus and zoom keep working exactly as before.

<Camera
  onTapToFocus={(e) => {
    console.log('tapped at', e.nativeEvent.x, e.nativeEvent.y);
  }}
/>

Three decisions worth surfacing:

• Not called onFocus, as the issue suggested. CameraProps extends ViewProps, and React Native declares onFocus/onBlur there for accessibility focus (ViewPropTypes.js), so reusing the name would shadow it.
• Coordinates are normalized 0–1 of the preview, not raw points, so payloads don't depend on device pixel dimensions. That matches the bounds onFaceDetected already documents.
• No new gesture recognizers. The event rides the existing tap handler, so nothing changes for anyone not passing the prop, and there's no new way for gestures to conflict. On iOS that does mean it requires focusMode="on" (the default), since that's when the tap gesture is attached — documented on the prop.

The plumbing mirrors onZoom exactly: codegen spec → public prop → an RCTDirectEventBlock exported for the old architecture and forwarded to the generated event emitter for the new one; on Android an Event subclass registered in both the newarch and oldarch view managers. FocusInterfaceView does the normalization on iOS since it owns that coordinate space, which also keeps CameraView.swift from growing further past SwiftLint's file_length limit.

Testing

• yarn build (tsc) — clean.
• Codegen verified rather than assumed. Ran react-native codegen --platform ios --source library and checked the generated header: struct OnTapToFocus { double x; double y; };, which is exactly what the new-arch designated initializer in CKCameraViewComponentView.mm constructs.
• Android example built as CI does — yarn && cd example/android && ./gradlew assembleDebug → BUILD SUCCESSFUL, 91 tasks, app-debug.apk produced. TapToFocusEvent.class, CKCamera.class and CKCameraManager.class all compiled (the example has newArchEnabled=true, so this exercises the newarch manager — same as CI).
• SwiftLint over the changed Swift files reports the same six pre-existing violations as master and no new ones. It needs SourceKit, so with only the Command Line Tools installed it has to be pointed at the CLT copy: DYLD_FRAMEWORK_PATH=/Library/Developer/CommandLineTools/usr/lib swiftlint -- <files>.

What I could not verify locally: the iOS example build, which needs a full Xcode install rather than the Command Line Tools. The iOS code is the part I'd look hardest at in review, particularly the new-arch block in CKCameraViewComponentView.mm.

One unrelated thing I noticed while setting up: yarn lint is eslint -c .eslintrc.js with no file arguments, so it lints nothing and exits 0 — the ESLint CI job passes regardless of what's in src/. And yarn test is declared but jest isn't a dependency. Happy to open a separate PR for either if useful; I've left both alone here.

Fixes #590

🤖 Generated with Claude Code

https://claude.ai/code/session_01MjiwHkBNkrUKxsQUVeeaSH

[SproutSeeds]

I tested 36be2b6 and found two Android callback problems: lifting the last finger after a pinch emits onTapToFocus, and queued discrete taps can be combined into one callback.

I opened a four file correction against your branch. It suppresses the new callback after multiple pointer input, keeps tap events from coalescing and clarifies the iOS focusMode requirement. Existing native focus and zoom handling retain their behavior.

Your PR fails three subscribed pinch assertions in each Android renderer. Three controlled Paper trials each accept four native window taps but produce one callback. The correction passes both controls. Final Paper and Fabric each pass 44 checks covering gestures, cancellation, callback removal/restoration, remounts, queued delivery and ten Home returns. The full iOS Paper suite passes three methods; I also confirmed focus, zoom and callback behavior on my iPhone 15 Pro Max.

Source fixtures, exact commits, commands, results and screenshots are available for reproduction. Android builds and TypeScript pass; iOS controls build with CLT clang 17. Default clang 21, Jest and explicit ESLint have matching baseline setup failures. The report retains earlier failed attempts and distinguishes the bundled queue tests from incomplete debug stress. Physical Android optics and hosted execution remain unverified; upstream workflows await approval with zero jobs.

Cody