Pre-Populated realm database with realm file

Question

I have contact.realm file with 10000 records in it. I want to use that preloaded realm file into my app.

Here is my code in app delegate's did finish launching :

// Inserting Contacts.Realm file to Default.Realm

let defaultPath = Realm.Configuration.defaultConfiguration.fileURL?.path
let path = Bundle.main.path(forResource: "ContactDemo", ofType: "realm")

if !FileManager.default.fileExists(atPath: defaultPath!), let bundledPath = path {
    do {
        try FileManager.default.copyItem(atPath: bundledPath, toPath: defaultPath!)
    } catch {
        print("Error copying pre-populated Realm \(error)")
    }
}

It works well for the first launch but when I delete the app and relaunch it I am getting 0 counts every time. The problem is that contents of conactDemo.realm is not getting copied into default.realm. Please help me out.

Answer 1

Go inside Realm class, put breakpoint into init() method and just check call trace.

You should replace this code:

let db = try! Realm() 

by this one:

lazy var db = try! Realm()

View controllers are instantiated from Storyboard BEFORE didFinishLaunchingWithOptions .

didFinishLaunchingWithOptions should be call before init() method of the Realm class.