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# activate(completionHandler:)

Prepares the manager for use.

```
func activate(completionHandler: @escaping @Sendable ((any Error)?) -> Void)
```

```
func activate() async throws
```

## Parameters

`completionHandler`

The completion handler that the framework calls when activation completes.

## Discussion

> Important:
> You can call this method from synchronous code using a completion handler, as shown on this page, or you can call it as an asynchronous method that has the following declaration:
> 
> ```swift
> func activate() async throws
> ```
> 
> For information about concurrency and asynchronous code in Swift, see <doc://com.apple.documentation/documentation/Swift/calling-objective-c-apis-asynchronously>.

> Important:
> This method is available in iOS 12.5, and in iOS 13.5 and later.

Properties may not be usable until the completion handler reports success.

---

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