# isContinuousAutoFocusTrackingEnabled Indicates whether the device should use continuous autofocus tracking. ``` var isContinuousAutoFocusTrackingEnabled: Bool { get set } ``` ## Discussion The default value for this property is `false`. On a device with an active format where `isContinuousAutoFocusTrackingSupported` returns `true` and [`isContinuousAutoFocusTrackingEnabled`](/documentation/AVFoundation/AVCaptureDevice/isContinuousAutoFocusTrackingEnabled) is set to `true`, continuous autofocus tracking will be engaged when the device’s focus mode is set to `AVCaptureFocusModeContinuousAutoFocus`. When engaged, the subject at the current [`focusPointOfInterest`](/documentation/AVFoundation/AVCaptureDevice/focusPointOfInterest) will be tracked as it moves within the scene and will be kept in focus automatically. The device’s [`isContinuousAutoFocusTrackingSubjectAcquired`](/documentation/AVFoundation/AVCaptureDevice/isContinuousAutoFocusTrackingSubjectAcquired) property will return `true` while any tracked subject remains in the scene. However, the device’s [`focusPointOfInterest`](/documentation/AVFoundation/AVCaptureDevice/focusPointOfInterest) and [`focusRectOfInterest`](/documentation/AVFoundation/AVCaptureDevice/focusRectOfInterest) are not updated while continuous autofocus tracking is active. Continuous autofocus tracking can be made inactive by setting [`isContinuousAutoFocusTrackingEnabled`](/documentation/AVFoundation/AVCaptureDevice/isContinuousAutoFocusTrackingEnabled) to `false` and then setting the device’s focus mode to `AVCaptureFocusModeContinuousAutoFocus` or by setting the focus mode to a value other than `AVCaptureFocusModeContinuousAutoFocus`. When made inactive, [`isContinuousAutoFocusTrackingSubjectAcquired`](/documentation/AVFoundation/AVCaptureDevice/isContinuousAutoFocusTrackingSubjectAcquired) changes to `false`, as no subject is being tracked. For virtual cameras, continuous autofocus tracking only works on the [`activePrimaryConstituent`](/documentation/AVFoundation/AVCaptureDevice/activePrimaryConstituent). To receive continuous autofocus tracking updates, it is required to connect this device to an [`AVCaptureMetadataOutput`](/documentation/AVFoundation/AVCaptureMetadataOutput) that is configured to deliver [`focusTrackedObject`](/documentation/AVFoundation/AVMetadataObject/ObjectType/focusTrackedObject). If [`focusTrackedObject`](/documentation/AVFoundation/AVMetadataObject/ObjectType/focusTrackedObject) is not subscribed, no updates will be provided for continuous autofocus tracking and the device’s [`isContinuousAutoFocusTrackingSubjectAcquired`](/documentation/AVFoundation/AVCaptureDevice/isContinuousAutoFocusTrackingSubjectAcquired) property remains to be `false`. > Throws: `NSInvalidArgumentException` if this property is set to `true` when the active format’s ``isContinuousAutoFocusTrackingSupported`` returns `false`. > Throws: `NSInvalidArgumentException` if this property is set to `true` when the device is configured for cinematic video capture. > Throws: `NSGenericException` if the device is not locked for configuration using ``doc://com.apple.avfoundation/documentation/AVFoundation/AVCaptureDevice/lockForConfiguration()``. --- Copyright © 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)