SwiftUI: List does not update automatically after deleting all Core Data Entity entries

Question

I know SwiftUI uses state-driven rendering. So I was assuming, when I delete Core Data Entity entries, that my List with Core Data elements gets refreshed immediately. I use

Answer 1

The reason is that execute (as described in details below - pay attention on first sentence) does not affect managed objects context, so all fetched objects remains in context and UI represents what is really presented by context.

So in general, after this bulk operation you need to inform back to that code (not provided here) force sync and refetch everything.

API interface declaration

// Method to pass a request to the store without affecting the contents of the managed object context.
// Will return an NSPersistentStoreResult which may contain additional information about the result of the action
// (ie a batch update result may contain the object IDs of the objects that were modified during the update).
// A request may succeed in some stores and fail in others. In this case, the error will contain information
// about each individual store failure.
// Will always reject NSSaveChangesRequests.
@available(iOS 8.0, *)
open func execute(_ request: NSPersistentStoreRequest) throws -> NSPersistentStoreResult

For example it might be the following approach (scratchy)

// somewhere in View declaration
@State private var refreshingID = UUID()

...
// somewhere in presenting fetch results
ForEach(fetchedResults) { item in
    ...
}.id(refreshingID) // < unique id of fetched results

...

// somewhere in bulk delete 
try context.save() // < better to save everything pending
try context.execute(deleteRequest)
context.reset() // < reset context
self.refreshingID = UUID() // < force refresh