Load data into my app xcdatamodel - ios

Question

My app must start for end users with data already in the database so that info is displayed to them when they use the app.
My problem: how can I load the data into the app database?
There's an "import..." option on xcode (on Editor when selecting xcdatamodeld) but I cannot understand what is the file type required - I've tried .xls, .csv and .sqlite and none is "importable".
Help!

Answer 1

Add the database to your bundle when you ship your app. On initial startup, you look to see if the database lives in the local file system. If not (and it won't be the first time you start up), you copy the database from the bundle to the local file system, open it, and use it from there. Don't try to use it from the bundle, that's set to read only.
I'm assuming you're using a SQLite database or some other type of file. You can add a file to your bundle using these instructions: How do I add files to the resources folder in XCode?

Answer 2

If the data is already in the .sqlite format (see note below), copy that file to the project (move the file to the Xcode project directory, and then from Xcode choose File -> Add files to "Project name", and find the file in your computer directory.
In the main AppDelegate.m file under the persistentStoreCoordinator function (see this tutorial for setting up sqlite/Core Data in your project), write the code to copy from the main bundle resources to the app resources directory, if the file doesn't exist:
NSURL *dbUrl = [NSURL fileURLWithPath: [[self applicationDocumentsDirectory]
stringByAppendingPathComponent: #"yourDBName.sqlite"]];
if (![[NSFileManager defaultManager] fileExistsAtPath:[dbUrl path]]) {
NSURL *bundleURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:#"yourDBName" ofType:#"sqlite"]];
NSError* err = nil;
if (![[NSFileManager defaultManager] copyItemAtURL:bundleURL toURL:dbUrl error:&err]) {
NSLog(#"Could not copy main bundle data");
}
else { NSLog(#"Main bundle data successfully copied"); }
}
It is important that your preloaded .sqlite database from the main bundle have been created properly from within an Xcode project (iOS apps only recognize specially-formatted .sqlite files).
Once this is loaded, it will be recognized as the app's database as long as the Core Data managed object context has its persistent store coordinator set to this .sqlite file, and that its structure matches that of the core data model.