example

device_io example

A Flutter app exercising every device_io capability — pick, share, save, and open files through one API. Tap a button, watch the outcome land in the activity log. All demo bytes are generated in code; nothing touches assets or the network to start. Runs on macOS, iOS, Android, Windows, Linux, and web.

Run

cd example

# desktop
fvm flutter run -d macos

# web
fvm flutter run -d chrome

# any connected device
fvm flutter run -d <device>

Tests

# host-VM journey matrix — the UI driven end to end through the real
# adapters against scripted plugin edges, across every device profile;
# no device needed:
cd example
fvm flutter test test/journeys

# integration smoke — the programmatic surfaces against REAL plugins:
fvm flutter test integration_test/device_io_smoke_test.dart -d macos
fvm flutter test integration_test/device_io_smoke_test.dart -d <device>

# or from the package root:
cd ..
make test-example-matrix
make test-example-macos

# one real target at a time (CI's full-test runs each of these):
make test-example-android   # also: -ios, -linux, -windows, -web
make verify-macos           # release build; also: -android, -ios, -linux, -windows, -web

The host journeys stay in memory (no dart:io) — they drive the UI through the real adapters against scripted plugin edges where the adapter is seam-scriptable (pick, share); the io-bound flows (save, open) inject recording capabilities at the public DeviceIO.custom seam, so the journey proves the UI wiring and the adapter's own charter proves the adapter. Real filesystem effects (silent saves with the no-clobber proof, streamed saves, asset round-trips) live in the integration smoke, which runs on a real device where async I/O behaves normally. Pickers, share sheets, saveAs, and openers summon real dialogs and viewers, so they're exercised by the package suites and the journeys instead.

What's inside

Four tabs, one per API surface:

Tab	API	What it covers
Pick	picker	Gallery images (single + multi), camera capture, videos, mixed media, generic files. Picked assets are lazy — bytes are read on tap, never at pick time.
Share	sharer	Text, a single file, multiple files in one sheet, and a ~1MB byte stream.
Save	saver	Silent save to downloads, a streamed save, and the user-picks-destination system dialog.
Open	opener	In-memory bytes in the default viewer, and the last silently-saved path.

Every call returns a sealed Outcome; one renderer switches the family exhaustively and writes the outcome into the activity log, which sits below the tabs — global, so a result is never hidden by tab switching.

One file on purpose

The whole app lives in lib/main.dart because pub.dev renders that file as the package's Example tab — splitting it would hide everything else from that page.

Platform setup

The iOS Info.plist usage strings (photo library, camera, microphone) and the macOS user-selected read-write entitlements are already configured in this example — the same declarations the package README's Install section walks consumers through.