Devlog #7 ->
Part 2/2 (but part 1 of this devlog)
Okay. This was very annoying to work on because every single time I would edit the code, I would have to recommit in order to see it on the github pages (because the permissions wouldn’t work on the flutter web-server).
So, getting the guided camera working on web brought a whole lot of browser-specific issues that don’t show up on native mobile. First, the app would hang on a black loading screen because permission_handler and frame streaming aren’t supported in browsers. I then fixed that by branching on kIsWeb to skip those native-only calls and let the browser’s own getUserMedia prompt handle camera access instead.Next, iOS Safari blocked the camera request outright because it requires permission calls to fire directly from a user tap with no delay -> solved by gating the whole flow behind an explicit “Enable Camera” button instead of auto-starting on page load. Since camera_web doesn’t support live frame streaming and sensors_plus doesn’t handle iOS’s motion permission prompt, live guidance (tilt, brightness, sharpness) had to be rebuilt from scratch for web: a custom JS-interop layer (WebProbe) draws each video frame onto a hidden canvas to sample brightness/sharpness, and separately requests iOS’s DeviceMotionEvent permission to read tilt.That introduced two more subtle bugs (a Dart generics issue causing a null-cast crash in the interop code, and a timing issue where the element wasn’t in the DOM yet when we went looking for it) both fixed with explicit type arguments and a retry loop.
With all of that sorted, the guided camera now works consistently across native and web, with live tilt/lighting/sharpness feedback and autocapture.

View it here: https://mirage54321.github.io/RoboLens/