I'm developing an iOS app that handles custom file types (e.g., .k files), and I want to ensure my app's icon appears in Core Spotlight search results, similar to how 两步路户外助手's icon shows up for associated files (as shown in the attached screenshot from iOS search). I know one standard way is to configure CFBundleDocumentTypes in the Info.plist to declare supported document types, which allows the system to associate files with my app and display the icon in search. However, I'm looking for alternative approaches or additional configurations that could achieve this without relying solely on CFBundleDocumentTypes, or perhaps in combination with it for better integration. For context:
This is for iOS 26+ (or latest versions). The goal is to have the app icon visible directly in Spotlight/Core Spotlight results when searching for files or content indexed by my app. I've tried basic NSUserActivity and CSSearchableItem indexing, but the icon doesn't always appear as expected for file associations.
Has anyone implemented this through other means, like exported UTIs, Launch Services, or custom searchable attributes? Any code snippets, documentation links, or best practices would be appreciated!
(Attach your Figure 2 screenshot here to illustrate the desired behavior, e.g., the .k file with the app icon in search results.)