Platform setup · File Viewer Flutter

One Dart API targets six platforms through their WebView or Web DOM implementation. This release is a development preview; a platform tag does not qualify every device, OS version or document format.

Shared setup

Complete the quick start, then preview and apply host configuration from your application root:

dart run file_viewer_flutter:setup --project . --check
dart run file_viewer_flutter:setup --project . --apply

Only existing platform directories are processed. Run it again after adding a platform. Select a subset with --platform android,ios,macos; web is not an argument to this command.

Android

Initial target: Android API 24+, using the installed Android WebView.
Setup adds Internet permission and loopback-scoped local HTTP configuration. Existing custom settings are preserved or a conflict is reported for review.
No separate Android Service, perpetual background permission or foreground-service permission is required.
Fully rebuild the APK after changing host settings. Verify your actual device and installed WebView version.

Initial evidence: Xiaomi 12 Pro / API 35 / WebView 131, five owned fixtures, Worker/WASM execution, session reuse and document preload.

iOS

Initial target: iOS 15+, using WKWebView. Build on macOS with Xcode and Flutter's iOS tooling.
Setup handles Info.plist entries for local resources while preserving the meaning of your existing network policy.
The OS can suspend or reclaim background processes; see warm-up and lifecycle.

Initial evidence: iPhone 17 Pro / iOS 26.4 simulator. Physical iPhones/iPads, memory pressure and a broader document corpus remain stable-release gates.

Web

Uses browser DOM and same-origin static assets; native setup makes no Web changes.
Deploy the complete build/web/, including assets/packages/ and CanvasKit/Skwasm resources.
Browsers cannot open arbitrary native paths. Read a file-picker selection into FileViewerSource.bytes.
Authenticated cross-origin URLs remain subject to browser CORS.

flutter build web --no-web-resources-cdn

Initial evidence: Chrome 156, JavaScript and Dart WASM builds, five owned formats, and real Worker/WASM execution with external HTTP blocked. Mobile browsers need separate verification.

macOS

Initial target: macOS 12+, using WKWebView. Use Xcode and Flutter's macOS toolchain.
Setup adds Info.plist and sandbox network entitlements needed by local resources while preserving other settings.
Retained WKWebViews and document sessions use a fresh native container on each Flutter attachment, keeping one View from attaching to multiple Widgets.

Initial evidence: an Apple Silicon device and macOS 15 x64 / ARM64 CI. App signing and notarization remain part of your application's distribution process.

Windows

Initial target: Windows 10+, using a bundled, checksum-locked WebView2 Fixed Version Runtime.
Use Flutter's supported Windows / Visual Studio C++ build environment. Ship the complete release output and its bundled browser runtime.
The build prepares the locked engine archive; the application does not download an engine at runtime.

Initial evidence: Windows 2025 x64 and Windows 11 ARM64 CI, actual rendering and Microsoft runtime signature verification. Qualify other versions in your target environment.

Linux

Uses a bundled, checksum-locked CEF adapter with its sandbox preserved.
Typical build dependencies include clang, CMake, Ninja, pkg-config, GTK 3, ALSA, NSS, XSS and GBM; package names vary by distribution.
Setup adds CEF subprocess initialization and shutdown ordering to the Linux runner and connects its build configuration.
Systems allowing unprivileged user namespaces can use that sandbox path. Restricted distributions require a normal installer to assign the bundled chrome-sandbox helper its official root ownership and 4755 mode. Do not silently elevate the app or disable the sandbox.

Initial evidence: Ubuntu 24.04 x64 / ARM64 CI. Other distributions, display servers and real desktop visuals need separate checks.

The repository's qualification matrix records measured scope and remaining release gates. Test your own documents, devices, memory conditions and system WebViews. Another platform or desktop browser is not physical-iOS evidence.