# progressHandler A block Photos calls periodically while downloading the asset. ``` var progressHandler: ((Double, UnsafeMutablePointer) -> Void)? { get set } ``` ## Discussion If you request an asset whose data is not on the local device, and have enabled downloading with the [`isNetworkAccessAllowed`](/documentation/Photos/PHContentEditingInputRequestOptions/isNetworkAccessAllowed) property, Photos calls your block periodically to report progress and allow canceling the download. The block takes the following parameters: - progress: A floating-point value indicating the progress of the download. A value of `0.0` indicates the download has just started, and a value of `1.0` indicates the download is complete. - stop: A pointer to a Boolean value. Set `*stop` to `true` inside the block to cancel the download. --- 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)