<!--
{
  "availability" : [
    "iOS: 27.3.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "AccessoryTransportExtension",
  "identifier" : "/documentation/AccessoryTransportExtension/AccessoryWorker/Handler",
  "metadataVersion" : "0.1.0",
  "role" : "Type Alias",
  "symbol" : {
    "kind" : "Type Alias",
    "modules" : [
      "Accessory Transport Extension"
    ],
    "preciseIdentifier" : "s:27AccessoryTransportExtension0A6WorkerV7Handlera"
  },
  "title" : "AccessoryWorker.Handler"
}
-->

# AccessoryWorker.Handler

A handler type for the session’s data provider.

```
typealias Handler = AccessoryFeatureSessionHandler<AccessoryWorker.Session>
```

## Discussion

Conform your data provider extension’s handler to this type to receive events from an [`AccessoryWorker.Session`](/documentation/AccessoryTransportExtension/AccessoryWorker/Session). Because each feature uses its own `Handler` type alias, the compiler rejects a handler for this feature if you pass it to [`AccessoryGPUWorker`](/documentation/AccessoryTransportExtension/AccessoryGPUWorker) or another feature. Return an instance of your handler from the factory closure that you pass to [`init(_:)`](/documentation/AccessoryTransportExtension/AccessoryWorker/init(_:)).

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)