Use Realm in Xcode Playgrounds

Prerequisites

You can only use Swift packages within Xcode projects that have at least one scheme and target. To use Realm in Xcode Playgrounds, you must first have an Xcode project where you have Installed the Swift SDK.

Create a Playground

Within a project, go to File > New > Playground. Select the type of Playground you want. For this example, we've used a Blank iOS Playground.

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Name and save the playground in the root of your project. Be sure to add it to the project:

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You should see your new Playground in your Project navigator.

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Import Realm

Add the following import statement to use Realm in the playground:

import RealmSwift

Experiment with Realm

Experiment with Realm. For this example, we'll:

• Define a new Realm object type

• Create a new object of that type and write it to realm

• Query objects of the type, and filter them

class Drink: Object {
    @Persisted var name = ""
    @Persisted var rating = 0
    @Persisted var source = ""
    @Persisted var drinkType = ""
}
let drink = Drink(value: ["name": "Los Cabellos", "rating": 10, "source": "AeroPress", "drinkType": "Coffee"])
let realm = try! Realm(configuration: config)
try! realm.write {
    realm.add(drink)
}
let drinks = realm.objects(Drink.self)
let coffeeDrinks = drinks.where {
    $0.drinkType == "Coffee"
}
print(coffeeDrinks.first?.name)

Managing the Realm File in Your Playground

When you work with a default realm in a Playground, you might run into a situation where you need to delete the realm. For example, if you are experimenting with an object type and add properties to the object, you may get an error that you must migrate the realm.

You can specify Realm.configuration details to open the file at a specific path, and delete the realm if it exists at the path.

var config = Realm.Configuration()
config.fileURL!.deleteLastPathComponent()
config.fileURL!.appendPathComponent("playgroundRealm")
config.fileURL!.appendPathExtension("realm")
if Realm.fileExists(for: config) {
    try Realm.deleteFiles(for: config)
    print("Successfully deleted existing realm at path: \(config.fileURL!)")
} else {
    print("No file currently exists at path")
}

Alternately, you can open the realm in-memory only, or use the deleteRealmIfMigrationNeeded method to automatically delete a realm when migration is needed.