dual_screen_hinge geometric folding-device logo

dual_screen_hinge

Day-one Flutter access to continuous hinge angles, posture, feature geometry, screen role, and foldable display modes on Android and iOS.

Use it alongside MediaQuery

On Android, prefer MediaQuery.displayFeatures for adaptive layout and the basic opened/half-opened state Flutter already exposes. Use this plugin when you need continuous angles for animation, richer fold/hinge metadata, supported postures, rear/dual-screen display sessions, or iOS support.

Install

dependencies:
  dual_screen_hinge: ^0.1.0

Requires Flutter 3.38+, Dart 3.10+, Android API 21+, or iOS 13+. iPhone Duo hinge telemetry requires an app compiled with Xcode 27 and runs only when the public iOS hinge API reports hardware support.

Read state and animate

final subscription = DualScreenHinge.instance.events.listen((state) {
  print('${state.posture} ${state.hingeAngle}°');
});

StreamBuilder<double>(
  stream: DualScreenHinge.instance.hingeAngleEvents,
  builder: (context, snapshot) {
    final angle = snapshot.data ?? 180;
    return Transform.rotate(
      angle: (180 - angle) * math.pi / 180,
      child: const MyFoldEffect(),
    );
  },
);

The native event stream is shared by all Dart listeners, sends a snapshot on listen, deduplicates state, and coalesces sensor updates to approximately one per display frame.

Display modes (Android)

final capabilities = await DualScreenHinge.instance.capabilities();

if (capabilities.rearDisplay) {
  await DualScreenHinge.instance.startRearDisplay();
}

if (capabilities.dualScreenPresentation) {
  await DualScreenHinge.instance.startDualScreen(
    entrypoint: 'dualScreenSecondaryMain',
    arguments: ['initial payload'],
  );
}

@pragma('vm:entry-point')
void dualScreenSecondaryMain(List<String> arguments) {
  runApp(SecondaryDisplayApp(arguments: arguments));
}

Only one display session can be pending or active. V1 deliberately supports startup arguments, not a cross-engine message bus. On iOS, display-mode methods return DualScreenException(code: 'unsupported') because there is no equivalent app-controlled public session API.

Platform behavior

Capability	Android	iOS
Continuous angle	API 30+ `TYPE_HINGE_ANGLE` when present	iOS 27 `UIHingeInteraction` on supported hardware
Fold geometry/posture	AndroidX WindowManager 1.5.1	Hinge posture and active screen
Inner/outer identity	Only while a Window Area session establishes it	Compact outer / regular inner after hinge capability is confirmed
Rear-display transfer	Experimental Window Area API	Unsupported
Dual-screen presentation	Experimental Window Area API + secondary Flutter engine	Unsupported

No device allowlist, OEM reflection, or private API is used. Unsupported data is nullable or reported through runtime capabilities.

Documentation

See the documentation site, the complete wire contract, device matrix, the deployment guide, and testing guide. The example/ app includes a live fold animation and compares plugin output with MediaQuery.displayFeatures.

License

MIT. See LICENSE.