What's the best way to detect SwiftData changes? Ie, when a shortcut is ran, how do we update the main ui?

To detect changes in SwiftData and update the main UI when a shortcut is run, you can leverage the SwiftData history API. This API allows you to track changes in your data store over time and update your UI accordingly. Here are the steps you can follow:

Fetch SwiftData History: Use the history API to fetch transactions from the data store. You can configure constraints for your request to fetch only the relevant changes.
Process the Changes: Inspect the properties of the changes to determine what has been inserted, updated, or deleted.
Update the UI: Based on the processed changes, update your user interface to reflect the new state of the data.

Here's a more detailed breakdown:

Fetch SwiftData History:
- Build a function that fetches transactions in the data store based on a token parameter and author.
- Create a history descriptor to configure constraints for your request, such as fetching changes after a specific token or by a specific author.
Process the Changes:
- Iterate through the fetched transactions and inspect the properties of each change.
- Determine which models have been inserted, updated, or deleted.
Update the UI:
- Use the processed changes to update your UI. For example, you can badge items that have unread changes or refresh a list to show the latest data.

For a practical example, you can refer to the session Track model changes with SwiftData history where they demonstrate how to fetch SwiftData history, process the changes, and update the UI.

Additionally, the session SwiftUI essentials explains how SwiftUI automatically keeps your UI up to date when your view state changes, which can be useful when integrating with SwiftData.

Relevant Sessions

By following these steps and utilizing the SwiftData history API, you can efficiently detect changes and update your main UI when a shortcut is run.