API reference

SpecificDeviceSelector Class

Extends DeviceSelectorBase
 Modifiers: final
A device selector that always selects a specific, predetermined device. Use this when you want to target operations to a particular device by its identifier, such as when you have multiple devices paired and want to explicitly control which one receives commands or streams data.
Unlike AutoDeviceSelector, this selector only emits the specified device when it's present in the available device set, and null when it is removed. It does not automatically switch to other devices.
Example: 
// Get a specific device from the connected devices
val devices = Wearables.devices.value
val targetDevice = devices.firstOrNull { deviceId ->
    Wearables.devicesMetadata[deviceId]?.value?.name == "My Glasses"
}
// Create session targeting that specific device
targetDevice?.let { device ->
    val session = Wearables.createSession(
        SpecificDeviceSelector(device)
    )
}

See Also

Signature

class SpecificDeviceSelector(selectedDevice: DeviceIdentifier) : DeviceSelectorBase

Constructors

SpecificDeviceSelector ( selectedDevice )
Signature 
constructor(selectedDevice: DeviceIdentifier)
Parameters
selectedDevice: DeviceIdentifier  The identifier of the device to always select
Returns
SpecificDeviceSelector

Methods

activeDevice ()
Returns the currently selected device identifier, or null if no device is selected.
This provides synchronous access to the latest selected device. The value is eagerly cached from the underlying device selection flow, so it always reflects the most recent state without requiring flow collection.
Signature 
open override fun activeDevice(): DeviceIdentifier?
Returns
DeviceIdentifier?  The DeviceIdentifier of the currently selected device, or null if no suitable device is available
activeDeviceFlow ()
Returns a Flow that emits the currently selected device identifier, or null when no device is selected.
Use this to reactively observe device selection changes. The flow emits whenever the selected device changes — for example, when a device connects, disconnects, or when the selector switches to a different device.
Signature 
open override fun activeDeviceFlow(): Flow<DeviceIdentifier?>
Returns
Flow<DeviceIdentifier?>  A Flow of DeviceIdentifier representing the active device, or null when no suitable device is available