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# ar_session_set_data_provider_state_change_handler_f

Sets the handler function for responding to a state change of one or more data providers.

```
extern void ar_session_set_data_provider_state_change_handler_f(ar_session_t session, dispatch_queue_t queue, void *context, ar_session_data_provider_state_change_handler_function_t data_provider_state_change_handler_function);
```

## Parameters

`session`

The `ar_session_t` instance.

`queue`

The queue on which the function will be called. Passing NULL will default to the main queue.

`context`

The application-defined context parameter to pass to the function.

`data_provider_state_change_handler_function`

The data provider state change handler function.

## Discussion> Note: Setting this will override the handler set using `ar_session_set_data_provider_state_change_handler`.

---

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