---
title: trackingArea
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nsevent/trackingarea
---

# trackingArea

The tracking area for the event.

## Declaration

```swift
var trackingArea: NSTrackingArea? { get }
```

## Discussion

Discussion If you access this property on an event object that is not a mouse-tracking event — that is, its event type isn’t NSMouseEntered, NSMouseExited, or NSCursorUpdate —AppKit raises an internalInconsistencyException. If the event corresponds to a tracking rectangle installed with the addTrackingRect(_:owner:userData:assumeInside:) method of NSView, the value of this property is nil. The trackingNumber property contains either an NSTrackingArea object or NSView.TrackingRectTag, depending on how AppKit generated the event.

## See Also

### Getting tracking area information

- [eventNumber](appkit/nsevent/eventnumber.md)
- [trackingNumber](appkit/nsevent/trackingnumber.md)
- [userData](appkit/nsevent/userdata.md)