API reference
AutoDeviceSelector Class
Extends
DeviceSelectorBase
Modifiers:
final A device selector that automatically selects an optimal device from the provided device set. Uses a reactive stream approach that maintains device selection across connectivity changes, only switching devices when the currently selected device becomes disconnected or incompatible.
This selector is ideal for most applications that want to connect to any available device without requiring the user to manually select one. The selector continuously monitors device connectivity and compatibility, automatically switching to the best available device when the current device disconnects or becomes incompatible.
Example:
// Use default selection (first connected, compatible device)
val session = Wearables.createSession(AutoDeviceSelector())
// Custom ranking: prefer devices by name
val customRanking = Comparator<Device> { a, b -> a.name.compareTo(b.name) }
val session = Wearables.createSession(AutoDeviceSelector(customRanking))
See Also
- DeviceSelector for the base interface
- SpecificDeviceSelector for targeting a specific device
- Device for available device properties
- Wearables.createSession for creating a session with a selector
Constructors
AutoDeviceSelector
(
deviceRanking
, filter
)
|
Signature
constructor(deviceRanking: Comparator<Device>), filter: (Device) -> Boolean = { true })Parameters deviceRanking: Comparator<Device>
A comparator function used to rank and select from connected devices when the current device is no longer connected or compatible. The default ranking prioritizes connected devices first.
filter: Function1
An additional filter applied on top of the default connected and compatible check. Only devices that are both connected/compatible AND pass this filter will be considered. The default accepts all connected and compatible devices.
Returns AutoDeviceSelector |
Methods
activeDevice
()
|
Returns the currently selected device identifier, or null if no devices match AutoDeviceSelector.filter.
Falls back to a synchronous lookup when the async flow in DeviceSelectorBase has not yet emitted (e.g. immediately after construction).
Signature
open override fun activeDevice(): DeviceIdentifier? Returns DeviceIdentifier? |
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
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