AnyRealmCollection

public final class AnyRealmCollection<T: Object>: RealmCollectionType

A type-erased RealmCollectionType.

Forwards operations to an arbitrary underlying collection having the same Element type, hiding the specifics of the underlying RealmCollectionType.

  • Element type contained in this collection.

    Declaration

    Swift

    public typealias Element = T
  • Returns the object at the given index.

    Declaration

    Swift

    public subscript(index: Int) -> T { return base[index] }

    Parameters

    index

    The index.

    Return Value

    The object at the given index.

  • Creates an AnyRealmCollection wrapping base.

    Declaration

    Swift

    public init<C: RealmCollectionType where C.Element == T>(_ base: C)
  • The Realm the objects in this collection belong to, or nil if the collection’s owning object does not belong to a realm (the collection is standalone).

    Declaration

    Swift

    public var realm: Realm? { return base.realm }
  • Returns the number of objects in this collection.

    Declaration

    Swift

    public var count: Int { return base.count }
  • Returns a human-readable description of the objects contained in this collection.

    Declaration

    Swift

    public var description: String { return base.description }
  • Returns the index of the given object, or nil if the object is not in the collection.

    Declaration

    Swift

    public func indexOf(object: Element) -> Int? { return base.indexOf(object) }

    Parameters

    object

    The object whose index is being queried.

    Return Value

    The index of the given object, or nil if the object is not in the collection.

  • Returns the index of the first object matching the given predicate, or nil no objects match.

    Declaration

    Swift

    public func indexOf(predicate: NSPredicate) -> Int? { return base.indexOf(predicate) }

    Parameters

    predicate

    The NSPredicate used to filter the objects.

    Return Value

    The index of the first matching object, or nil if no objects match.

  • Returns the index of the first object matching the given predicate, or nil if no objects match.

    Declaration

    Swift

    public func indexOf(predicateFormat: String, _ args: AnyObject...) -> Int?

    Parameters

    predicateFormat

    The predicate format string, optionally followed by a variable number of arguments.

    Return Value

    The index of the first matching object, or nil if no objects match.

  • Returns Results containing collection elements that match the given predicate.

    Declaration

    Swift

    public func filter(predicateFormat: String, _ args: AnyObject...) -> Results<Element>

    Parameters

    predicateFormat

    The predicate format string which can accept variable arguments.

    Return Value

    Results containing collection elements that match the given predicate.

  • Returns Results containing collection elements that match the given predicate.

    Declaration

    Swift

    public func filter(predicate: NSPredicate) -> Results<Element> { return base.filter(predicate) }

    Parameters

    predicate

    The predicate to filter the objects.

    Return Value

    Results containing collection elements that match the given predicate.

  • Returns Results containing collection elements sorted by the given property.

    Declaration

    Swift

    public func sorted(property: String, ascending: Bool) -> Results<Element>

    Parameters

    property

    The property name to sort by.

    ascending

    The direction to sort by.

    Return Value

    Results containing collection elements sorted by the given property.

  • Returns Results with elements sorted by the given sort descriptors.

    Declaration

    Swift

    public func sorted<S: SequenceType where S.Generator.Element == SortDescriptor>
                          (sortDescriptors: S) -> Results<Element>

    Parameters

    sortDescriptors

    SortDescriptors to sort by.

    Return Value

    Results with elements sorted by the given sort descriptors.

  • Returns the minimum value of the given property.

    Warning

    Only names of properties of a type conforming to the MinMaxType protocol can be used.

    Declaration

    Swift

    public func min<U: MinMaxType>(property: String) -> U? { return base.min(property) }

    Parameters

    property

    The name of a property conforming to MinMaxType to look for a minimum on.

    Return Value

    The minimum value for the property amongst objects in the collection, or nil if the collection is empty.

  • Returns the maximum value of the given property.

    Warning

    Only names of properties of a type conforming to the MinMaxType protocol can be used.

    Declaration

    Swift

    public func max<U: MinMaxType>(property: String) -> U? { return base.max(property) }

    Parameters

    property

    The name of a property conforming to MinMaxType to look for a maximum on.

    Return Value

    The maximum value for the property amongst objects in the collection, or nil if the collection is empty.

  • Returns the sum of the given property for objects in the collection.

    Warning

    Only names of properties of a type conforming to the AddableType protocol can be used.

    Declaration

    Swift

    public func sum<U: AddableType>(property: String) -> U { return base.sum(property) }

    Parameters

    property

    The name of a property conforming to AddableType to calculate sum on.

    Return Value

    The sum of the given property over all objects in the collection.

  • Returns the average of the given property for objects in the collection.

    Warning

    Only names of properties of a type conforming to the AddableType protocol can be used.

    Declaration

    Swift

    public func average<U: AddableType>(property: String) -> U? { return base.average(property) }

    Parameters

    property

    The name of a property conforming to AddableType to calculate average on.

    Return Value

    The average of the given property over all objects in the collection, or nil if the collection is empty.

  • Returns a GeneratorOf<T> that yields successive elements in the collection.

    Declaration

    Swift

    public func generate() -> RLMGenerator<T> { return base.generate() }
  • The position of the first element in a non-empty collection. Identical to endIndex in an empty collection.

    Declaration

    Swift

    public var startIndex: Int { return base.startIndex }
  • The collection’s past the end position. endIndex is not a valid argument to subscript, and is always reachable from startIndex by zero or more applications of successor().

    Declaration

    Swift

    public var endIndex: Int { return base.endIndex }
  • Returns an Array containing the results of invoking valueForKey(_:) using key on each of the collection’s objects.

    Declaration

    Swift

    public func valueForKey(key: String) -> AnyObject? { return base.valueForKey(key) }

    Parameters

    key

    The name of the property.

    Return Value

    Array containing the results of invoking valueForKey(_:) using key on each of the collection’s objects.

  • Returns an Array containing the results of invoking valueForKeyPath(_:) using keyPath on each of the collection’s objects.

    Declaration

    Swift

    public func valueForKeyPath(keyPath: String) -> AnyObject? { return base.valueForKeyPath(keyPath) }

    Parameters

    keyPath

    The key path to the property.

    Return Value

    Array containing the results of invoking valueForKeyPath(_:) using keyPath on each of the collection’s objects.

  • Invokes setValue(_:forKey:) on each of the collection’s objects using the specified value and key.

    Warning

    This method can only be called during a write transaction.

    Declaration

    Swift

    public func setValue(value: AnyObject?, forKey key: String) { base.setValue(value, forKey: key) }

    Parameters

    value

    The object value.

    key

    The name of the property.

  • Register a block to be called each time the collection changes.

    The block will be asynchronously called with the initial collection, and then called again after each write transaction which changes the collection or any of the items in the collection.

    The block is called on the same thread as it was added on, and can only be added on threads which are currently within a run loop. Unless you are specifically creating and running a run loop on a background thread, this normally will only be the main thread.

    Notifications can’t be delivered as long as the runloop is blocked by other activity. When notifications can’t be delivered instantly, multiple notifications may be coalesced. That can include the notification about the initial collection.

    You must retain the returned token for as long as you want updates to continue to be sent to the block. To stop receiving updates, call stop() on the token.

    Declaration

    Swift

    public func addNotificationBlock(block: (collection: AnyRealmCollection<Element>?,
                                                 error: NSError?) -> ()) -> NotificationToken

    Parameters

    block

    The block to be called each time the collection changes.

    Return Value

    A token which must be held for as long as you want notifications to be delivered.

  • Register a block to be called each time the collection changes.

    The block will be asynchronously called with the initial results, and then called again after each write transaction which changes either any of the objects in the collection, or which objects are in the collection.

    At the time when the block is called, the collection object will be fully evaluated and up-to-date, and as long as you do not perform a write transaction on the same thread or explicitly call realm.refresh(), accessing it will never perform blocking work.

    Notifications are delivered via the standard run loop, and so can’t be delivered while the run loop is blocked by other activity. When notifications can’t be delivered instantly, multiple notifications may be coalesced into a single notification. This can include the notification with the initial collection. For example, the following code performs a write transaction immediately after adding the notification block, so there is no opportunity for the initial notification to be delivered first. As a result, the initial notification will reflect the state of the Realm after the write transaction.

    let results = realm.objects(Dog)
    print("dogs.count: \(dogs?.count)") // => 0
    let token = dogs.addNotificationBlock { (changes: RealmCollectionChange) in
        switch changes {
            case .Initial(let dogs):
                // Will print "dogs.count: 1"
                print("dogs.count: \(dogs.count)")
                break
            case .Update:
                // Will not be hit in this example
                break
            case .Error:
                break
        }
    }
    try! realm.write {
        let dog = Dog()
        dog.name = "Rex"
        person.dogs.append(dog)
    }
    // end of run loop execution context
    

    You must retain the returned token for as long as you want updates to continue to be sent to the block. To stop receiving updates, call stop() on the token.

    Warning

    This method cannot be called during a write transaction, or when the source realm is read-only.

    Declaration

    Swift

    public func addNotificationBlock(block: (RealmCollectionChange<AnyRealmCollection>) -> ())
            -> NotificationToken { return base._addNotificationBlock(block) }

    Parameters

    block

    The block to be called with the evaluated collection and change information.

    Return Value

    A token which must be held for as long as you want updates to be delivered.