Last updated: 2026-11-10

Everything goes through one object, EvenDevicesNative.instance, and one event stream. Methods return once the request is submitted. The result of a connection, a time sync or a page arrives later as an event. This page uses the Flutter API. For Kotlin and Swift, see Native Android and iOS.

The flow

1. Listen to events.
2. Ask for Bluetooth permissions.
3. Initialize with your license file.
4. Scan and collect both sides of a pair of glasses.
5. Connect, then wait for the whole device to be ready.
6. Send commands.

Listen first

Subscribe before you call anything else. The SDK does not replay earlier events, so a listener added later misses them.

final sdk = EvenDevicesNative.instance;
final found = <String, Map<String, G2Endpoint>>{};
var ready = false;

final subscription = sdk.events.listen((event) {
  if (event.type == 'discovery' && event.sn != null) {
    final sides = found.putIfAbsent(event.sn!, () => {});
    for (final device in event.devices) {
      sides[device.side] = device;
    }
  }
  if (event.type == 'g2' && event.phase == 'ready' && event.side == null) {
    ready = true;
  }
  if (event.type == 'g2' &&
      (event.phase == 'disconnected' || event.phase == 'failed')) {
    ready = false;
  }
});

Initialize

if (!await sdk.requestBluetoothPermissions()) {
  throw StateError('Bluetooth permission denied');
}

await sdk.initialize(
  namespace: accountId,
  licenseJson: await rootBundle.loadString('assets/com.example.app.licenses.json'),
);

• namespace identifies this session in every event, for example the signed-in user of your app.
• licenseJson is the whole license file, passed as text. The native SDK validates it and throws a PlatformException if it is invalid.

Scan

await sdk.scan();

Each discovery event carries the serial number in sn and the sides found so far in devices, each with its side (left or right), address and name. The two sides may arrive in separate events. A discovered device is not yet authorized.

Stop scanning with await sdk.stopScan().

Connect

Once both sides of a serial number have appeared, connect:

final sides = found[sn]!;
await sdk.connectG2(sn: sn, left: sides['left'], right: sides['right']);

• Android needs both scanned sides.
• iOS takes both sides or neither. With neither, it looks them up from its own scan results. Passing only one side is rejected.

The SDK picks the license for that exact serial number from your license file and checks it on each side, then authenticates. A serial number with no license in the file is refused before any connection starts.

Ready

Each side reports its progress in g2 events with side set to left or right. The whole device is ready when a g2 event arrives with phase == 'ready' and side == null. Send commands only after that event.

phase	Meaning
waitingForForeground	iOS: waiting for the app to come to the foreground
connecting	Bluetooth connection in progress
enterpriseAuthorizing	The glasses are checking your license
businessAuthenticating	Authentication after the license check
retrying	A side is retrying
ready	With side == null: the whole device is ready
disconnected	The connection ended
failed	The attempt failed; the reason is in failure

Time sync

After the device is ready, set the glasses clock from the phone:

await sdk.syncG2Time();

The result arrives as a timeSync event with success, and failure when it did not succeed. The SDK refuses a time sync while an EvenHub page is open.

Update licenses

After you add devices in the portal, download the license file again and pass it in:

await sdk.updateLicenses(newLicenseJson);

The SDK validates the whole file before replacing the old one. New connections use the new file.

Disconnect and reset

await sdk.disconnectG2();
await sdk.reset();
await subscription.cancel();

• Call reset() when the user signs out, switches accounts or the app shuts down. It tears down the native session and its pending callbacks.
• Cancelling the subscription only removes your listener. It does not disconnect the glasses.
• Use one EvenDevicesNative.instance per process, from a single Flutter engine.

Events

type	Carries
discovery	Serial number and the sides found, before any authorization
g2	Connection and license-check progress per side, and the whole-device ready
timeSync	The result of syncG2Time()
evenHub	Page lifecycle, user input and microphone audio, see EvenHub pages
ota	Firmware update phase, operation ID and progress, see Firmware updates
transport, business	Platform diagnostics; never a sign of readiness

Events also carry namespace, sn and side where they apply, and details, a map with every field the native SDK sent.