setPrimaryConstituentDeviceSwitchingBehaviorLockedWith(_:)

Declaration

func setPrimaryConstituentDeviceSwitchingBehaviorLockedWith(_ device: AVCaptureDevice)

Parameters

• device:

  The constituent device to lock.

Discussion

Before locking a virtual camera’s primary constituent device, check that isPrimaryConstituentDeviceSwitchingBehaviorLockedWithDeviceSupported is true. If locking is not supported, attempting to lock throws an NSInvalidArgumentException. Call lockForConfiguration() to acquire exclusive access to the device’s configuration properties. Once a constituent device is locked, it becomes the activePrimaryConstituent, and primaryConstituentDeviceSwitchingBehavior is updated to AVCapturePrimaryConstituentDeviceSwitchingBehaviorLocked. The virtual camera’s properties remain unchanged. Their effective values can be obtained from the activePrimaryConstituent. To unlock the primary constituent device, set primaryConstituentDeviceSwitchingBehavior to AVCapturePrimaryConstituentDeviceSwitchingBehaviorAuto. This may trigger an immediate update of activePrimaryConstituent. Locking a different primary constituent device without first unlocking the current one is allowed.

If the current videoZoomFactor is within the constituent device’s supported range, it will remain unchanged. If it falls outside the range, the zoom factor will automatically be clamped to the nearest supported value. If a zoom ramp is in progress, the ramp target and current position will similarly be updated to stay within the supported range. If both the target and position are thus clamped to the same value, this will cancel the ramp at that value, otherwise the ramp will continue within the remaining available range at its current velocity.