---
title: didStartGathering
framework: foundation
role: symbol
role_heading: Type Property
path: foundation/notificationcenter/messageidentifier/didstartgathering
---

# didStartGathering

An identifier for a message about a metadata query that is starting its initial result gathering.

## Declaration

```swift
static var didStartGathering: NotificationCenter.BaseMessageIdentifier<NSMetadataQuery.DidStartGatheringMessage> { get }
```

## Discussion

Discussion Use this identifier with NotificationCenter’s addObserver(of:for:using:) or messages(of:for:bufferSize:) methods to observe messages of type NSMetadataQuery.DidStartGatheringMessage.

## See Also

### Identifying metadata query messages

- [didFinishGathering](foundation/notificationcenter/messageidentifier/didfinishgathering.md)