My approach is to let userId be an empty string if there are no users.
class Item: Object, ObjectKeyIdentifiable {
@Persisted(primaryKey: true) var _id: ObjectId
@Persisted var userId: String
@Persisted var name: String
convenience init(name: String, userId: String? = nil) {
self.init()
self.name = name
if let userId = userId {
self.userId = userId
}
}
}
I change the configuration environment depending on whether there is a logged in user.
struct ContentView: View {
@ObservedObject var app = Realm.app
var body: some View {
if let config = app.createFlexibleConfiguration() {
MainScreenSync()
.environment(\.realmConfiguration, config)
.environmentObject(app)
} else {
MainScreen()
.environmentObject(app)
}
}
}
Then, I rely on the SwiftUI syntax to easily access the synced realm.
struct MainScreenSync: View{
@EnvironmentObject var app: RealmSwift.App
// @Environment(\.realm) var syncedRealm
@ObservedResults(Item.self) var syncedItems
var body: some View {
VStack {
MainScreen()
Text(app.currentUser?.description ?? "not logged in")
}
.onAppear {
if let localRealm = try? Realm(), let user = app.currentUser {
let localItems = localRealm.objects(Item.self)
for item in localItems {
// local -> synced
let syncedItem = Item(value: item)
syncedItem.userId = user.id
$syncedItems.append(syncedItem)
// delete local
try? localRealm.write {
localRealm.delete(item)
}
}
}
}
}
}