据我所知，我们可以在 Apple Watch 应用上使用 Core Data。因此，独立的 watchOS 应用程序可以拥有自己的持久存储。但是当我们为 watchOS 应用程序创建项目时，没有使用核心数据的选项（就像我们为 iOS 应用程序创建项目时一样）
那么，如何在独立的 watchOS 应用上实现 Core Data 呢？
我从 iOS 应用程序（使用 Core Data）复制了这段代码，并将其粘贴到ExtensionDelegate我独立的 SwiftUI watchOS 应用程序中
// MARK: - Core Data stack
lazy var persistentContainer: NSPersistentContainer = {
/*
The persistent container for the application. This implementation
creates and returns a container, having loaded the store for the
application to it. This property is optional since there are legitimate
error conditions that could cause the creation of the store to fail.
*/
let container = NSPersistentContainer(name: "CoreDataToDo")
container.loadPersistentStores(completionHandler: { (storeDescription, error) in
if let error = error as NSError? {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
/*
Typical reasons for an error here include:
* The parent directory does not exist, cannot be created, or disallows writing.
* The persistent store is not accessible, due to permissions or data protection when the device is locked.
* The device is out of space.
* The store could not be migrated to the current model version.
Check the error message to determine what the actual problem was.
*/
fatalError("Unresolved error \(error), \(error.userInfo)")
}
})
return container
}()
// MARK: - Core Data Saving support
func saveContext () {
let context = persistentContainer.viewContext
if context.hasChanges {
do {
try context.save()
} catch {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
那么接下来我该怎么做呢？
还是我已经做错了？
请帮我。我已经努力寻找如何做到这一点。但是我找不到任何好的解决方案，因为以前没有独立的 watchOS 应用程序，所以大多数开发人员没有为 watchOS 应用程序创建单独的持久存储。
所以请帮助我。
谢谢。