领域：在Swift 2中使用变量查询

Question

absolute newbie-question: I have a model that consists of two objects in a Realm-database: Person and Dog. Person contains a list of Dogs. How can I query/filter for a list of dogs when the name of the Person is being handed over from a previous VC? For a tableView I need the query at the top of my VC-code. To access a single Person, I tried

personName: String! (derived from previous VC)     
let predicate = NSPredicate(format: "name = %@", personName)
let currentPerson = try! Realm().objects(Person).filter(predicate)

but I get

Instance member 'personName' cannot be used on type 'dogsVC'

What I want is simply list all the dogs of a specific person in a tableView.

Thanks in advance!

Answer 1

You will need to instantiate your predicate in viewDidLoad for example. Or make it a computed property:

var predicate:NSPredicate {
    return NSPredicate(format: "name = %@", personName)
}

And that's because you need to wait for your class to initialize before using self .