Realm
public struct Realm
A Realm
instance (also referred to as a Realm
) represents a Realm database.
Realms can either be stored on disk (see init(path:)
) or in memory (see Configuration
).
Realm
instances are cached internally, and constructing equivalent Realm
objects (for example,
by using the same path or identifier) produces limited overhead.
If you specifically want to ensure a Realm
instance is destroyed (for example, if you wish to
open a Realm, check some property, and then possibly delete the Realm file and re-open it), place
the code which uses the Realm within an autoreleasepool {}
and ensure you have no other strong
references to it.
Warning
warning Non-frozenRLMRealm
instances are thread-confined and cannot be
shared across threads or dispatch queues. Trying to do so will cause an
exception to be thrown. You must obtain an instance of RLMRealm
on each
thread or queue you want to interact with the Realm on. Realms can be confined
to a dispatch queue rather than the thread they are opened on by explicitly
passing in the queue when obtaining the RLMRealm
instance. If this is not
done, trying to use the same instance in multiple blocks dispatch to the same
queue may fail as queues are not always run on the same thread.
-
The
Configuration
value that was used to create theRealm
instance.Declaration
Swift
public var configuration: Configuration { get }
-
Indicates if the Realm contains any objects.
Declaration
Swift
public var isEmpty: Bool { get }
-
Obtains an instance of the default Realm.
The default Realm is persisted as default.realm under the Documents directory of your Application on iOS, and in your application’s Application Support directory on OS X.
The default Realm is created using the default
Configuration
, which can be changed by setting theRealm.Configuration.defaultConfiguration
property to a new value.Throws
AnNSError
if the Realm could not be initialized.Declaration
Swift
public init(queue: DispatchQueue? = nil) throws
Parameters
queue
An optional dispatch queue to confine the Realm to. If given, this Realm instance can be used from within blocks dispatched to the given queue rather than on the current thread.
-
Obtains a
Realm
instance with the given configuration.Throws
An
NSError
if the Realm could not be initialized.Declaration
Swift
public init(configuration: Configuration, queue: DispatchQueue? = nil) throws
Parameters
configuration
A configuration value to use when creating the Realm.
queue
An optional dispatch queue to confine the Realm to. If given, this Realm instance can be used from within blocks dispatched to the given queue rather than on the current thread.
-
Obtains a
Realm
instance persisted at a specified file URL.Throws
An
NSError
if the Realm could not be initialized.Declaration
Swift
public init(fileURL: URL) throws
Parameters
fileURL
The local URL of the file the Realm should be saved at.
-
Asynchronously open a Realm and deliver it to a block on the given queue.
Opening a Realm asynchronously will perform all work needed to get the Realm to a usable state (such as running potentially time-consuming migrations) on a background thread before dispatching to the given queue. In addition, synchronized Realms wait for all remote content available at the time the operation began to be downloaded and available locally.
The Realm passed to the callback function is confined to the callback queue as if
Realm(configuration:queue:)
was used.Declaration
Swift
@discardableResult public static func asyncOpen(configuration: Realm.Configuration = .defaultConfiguration, callbackQueue: DispatchQueue = .main, callback: @escaping (Realm?, Swift.Error?) -> Void) -> AsyncOpenTask
Parameters
configuration
A configuration object to use when opening the Realm.
callbackQueue
The dispatch queue on which the callback should be run.
callback
A callback block. If the Realm was successfully opened, an it will be passed in as an argument. Otherwise, a
Swift.Error
describing what went wrong will be passed to the block instead.Return Value
A task object which can be used to observe or cancel the async open.
-
A task object which can be used to observe or cancel an async open.
When a synchronized Realm is opened asynchronously, the latest state of the Realm is downloaded from the server before the completion callback is invoked. This task object can be used to observe the state of the download or to cancel it. This should be used instead of trying to observe the download via the sync session as the sync session itself is created asynchronously, and may not exist yet when Realm.asyncOpen() returns.
See moreDeclaration
Swift
public struct AsyncOpenTask
-
Performs actions contained within the given block inside a write transaction.
If the block throws an error, the transaction will be canceled and any changes made before the error will be rolled back.
Only one write transaction can be open at a time for each Realm file. Write transactions cannot be nested, and trying to begin a write transaction on a Realm which is already in a write transaction will throw an exception. Calls to
write
fromRealm
instances for the same Realm file in other threads or other processes will block until the current write transaction completes or is cancelled.Before beginning the write transaction,
write
updates theRealm
instance to the latest Realm version, as ifrefresh()
had been called, and generates notifications if applicable. This has no effect if the Realm was already up to date.You can skip notifiying specific notification blocks about the changes made in this write transaction by passing in their associated notification tokens. This is primarily useful when the write transaction is saving changes already made in the UI and you do not want to have the notification block attempt to re-apply the same changes.
The tokens passed to this function must be for notifications for this Realm which were added on the same thread as the write transaction is being performed on. Notifications for different threads cannot be skipped using this method.
Throws
An
NSError
if the transaction could not be completed successfully. Ifblock
throws, the function throws the propagatedErrorType
instead.Declaration
Swift
@discardableResult public func write<Result>(withoutNotifying tokens: [NotificationToken] = [], _ block: (() throws -> Result)) throws -> Result
Parameters
tokens
An array of notification tokens which were returned from adding callbacks which you do not want to be notified for the changes made in this write transaction.
block
The block containing actions to perform.
Return Value
The value returned from the block, if any.
-
Begins a write transaction on the Realm.
Only one write transaction can be open at a time for each Realm file. Write transactions cannot be nested, and trying to begin a write transaction on a Realm which is already in a write transaction will throw an exception. Calls to
beginWrite
fromRealm
instances for the same Realm file in other threads or other processes will block until the current write transaction completes or is cancelled.Before beginning the write transaction,
beginWrite
updates theRealm
instance to the latest Realm version, as ifrefresh()
had been called, and generates notifications if applicable. This has no effect if the Realm was already up to date.It is rarely a good idea to have write transactions span multiple cycles of the run loop, but if you do wish to do so you will need to ensure that the Realm participating in the write transaction is kept alive until the write transaction is committed.
Declaration
Swift
public func beginWrite()
-
Commits all write operations in the current write transaction, and ends the transaction.
After saving the changes and completing the write transaction, all notification blocks registered on this specific
Realm
instance are called synchronously. Notification blocks forRealm
instances on other threads and blocks registered for any Realm collection (including those on the current thread) are scheduled to be called synchronously.You can skip notifiying specific notification blocks about the changes made in this write transaction by passing in their associated notification tokens. This is primarily useful when the write transaction is saving changes already made in the UI and you do not want to have the notification block attempt to re-apply the same changes.
The tokens passed to this function must be for notifications for this Realm which were added on the same thread as the write transaction is being performed on. Notifications for different threads cannot be skipped using this method.
Warning
This method may only be called during a write transaction.
Throws
An
NSError
if the transaction could not be written due to running out of disk space or other i/o errors.Declaration
Swift
public func commitWrite(withoutNotifying tokens: [NotificationToken] = []) throws
Parameters
tokens
An array of notification tokens which were returned from adding callbacks which you do not want to be notified for the changes made in this write transaction.
-
Reverts all writes made in the current write transaction and ends the transaction.
This rolls back all objects in the Realm to the state they were in at the beginning of the write transaction, and then ends the transaction.
This restores the data for deleted objects, but does not revive invalidated object instances. Any
Object
s which were added to the Realm will be invalidated rather than becoming unmanaged.Given the following code:
let oldObject = objects(ObjectType).first! let newObject = ObjectType() realm.beginWrite() realm.add(newObject) realm.delete(oldObject) realm.cancelWrite()
Both
oldObject
andnewObject
will returntrue
forisInvalidated
, but re-running the query which providedoldObject
will once again return the valid object.KVO observers on any objects which were modified during the transaction will be notified about the change back to their initial values, but no other notifcations are produced by a cancelled write transaction.
Warning
This method may only be called during a write transaction.Declaration
Swift
public func cancelWrite()
-
Indicates whether the Realm is currently in a write transaction.
Warning
Do not simply check this property and then start a write transaction whenever an object needs to be created, updated, or removed. Doing so might cause a large number of write transactions to be created, degrading performance. Instead, always prefer performing multiple updates during a single transaction.Declaration
Swift
public var isInWriteTransaction: Bool { get }
-
What to do when an object being added to or created in a Realm has a primary key that already exists.
See moreDeclaration
Swift
public enum UpdatePolicy : Int
-
Adds an unmanaged object to this Realm.
If an object with the same primary key already exists in this Realm, it is updated with the property values from this object as specified by the
UpdatePolicy
selected. The update policy must be.error
for objects with no primary key.Adding an object to a Realm will also add all child relationships referenced by that object (via
Object
andList<Object>
properties). Those objects must also be valid objects to add to this Realm, and the value of theupdate:
parameter is propagated to those adds.The object to be added must either be an unmanaged object or a valid object which is already managed by this Realm. Adding an object already managed by this Realm is a no-op, while adding an object which is managed by another Realm or which has been deleted from any Realm (i.e. one where
isInvalidated
istrue
) is an error.To copy a managed object from one Realm to another, use
create()
instead.Warning
This method may only be called during a write transaction.
Declaration
Swift
public func add(_ object: Object, update: UpdatePolicy = .error)
Parameters
object
The object to be added to this Realm.
update
What to do if an object with the same primary key alredy exists. Must be
.error
for objects without a primary key. -
Adds all the objects in a collection into the Realm.
See
Warning
This method may only be called during a write transaction.
Declaration
Swift
public func add<S>(_ objects: S, update: UpdatePolicy = .error) where S : Sequence, S.Element : Object
Parameters
objects
A sequence which contains objects to be added to the Realm.
update
How to handle objects in the collection with a primary key that alredy exists in this Realm. Must be
.error
for object types without a primary key.update
How to handle objects in the collection with a primary key that alredy exists in this Realm. Must be
.error
for object types without a primary key. -
Creates a Realm object with a given value, adding it to the Realm and returning it.
The
value
argument can be a Realm object, a key-value coding compliant object, an array or dictionary returned from the methods inNSJSONSerialization
, or anArray
containing one element for each managed property. Do not pass in aLinkingObjects
instance, either by itself or as a member of a collection. If thevalue
argument is an array, all properties must be present, valid and in the same order as the properties defined in the model.If the object type does not have a primary key or no object with the specified primary key already exists, a new object is created in the Realm. If an object already exists in the Realm with the specified primary key and the update policy is
.modified
or.all
, the existing object will be updated and a reference to that object will be returned.If the object is being updated, all properties defined in its schema will be set by copying from
value
using key-value coding. If thevalue
argument does not respond tovalue(forKey:)
for a given property name (or getter name, if defined), that value will remain untouched. Nullable properties on the object can be set to nil by usingNSNull
as the updated value, or (if you are passing in an instance of anObject
subclass) setting the corresponding property onvalue
to nil.Warning
This method may only be called during a write transaction.
Declaration
Swift
@discardableResult public func create<T>(_ type: T.Type, value: Any = [:], update: UpdatePolicy = .error) -> T where T : Object
Parameters
type
The type of the object to create.
value
The value used to populate the object.
update
What to do if an object with the same primary key alredy exists. Must be
.error
for object types without a primary key.Return Value
The newly created object.
-
Deletes an object from the Realm. Once the object is deleted it is considered invalidated.
Warning
This method may only be called during a write transaction.
Declaration
Swift
public func delete(_ object: Object)
Parameters
object
The object to be deleted.
-
Deletes zero or more objects from the Realm.
Do not pass in a slice to a
Results
or any other auto-updating Realm collection type (for example, the type returned by the Swiftsuffix(_:)
standard library method). Instead, make a copy of the objects to delete usingArray()
, and pass that instead. Directly passing in a view into an auto-updating collection may result in ‘index out of bounds’ exceptions being thrown.Warning
This method may only be called during a write transaction.
Declaration
Swift
public func delete<S>(_ objects: S) where S : Sequence, S.Element : Object
Parameters
objects
The objects to be deleted. This can be a
List<Object>
,Results<Object>
, or any other SwiftSequence
whose elements areObject
s (subject to the caveats above). -
Deletes all objects from the Realm.
Warning
This method may only be called during a write transaction.Declaration
Swift
public func deleteAll()
-
Returns all objects of the given type stored in the Realm.
Declaration
Parameters
type
The type of the objects to be returned.
Return Value
A
Results
containing the objects. -
Retrieves the single instance of a given object type with the given primary key from the Realm.
This method requires that
primaryKey()
be overridden on the given object class.Declaration
Swift
public func object<Element, KeyType>(ofType type: Element.Type, forPrimaryKey key: KeyType) -> Element? where Element : Object
Parameters
type
The type of the object to be returned.
key
The primary key of the desired object.
Return Value
An object of type
type
, ornil
if no instance with the given primary key exists.
-
Adds a notification handler for changes made to this Realm, and returns a notification token.
Notification handlers are called after each write transaction is committed, independent of the thread or process.
Handler blocks are called on the same thread that they were added on, and may 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 will normally only be the main thread.
Notifications can’t be delivered as long as the run loop is blocked by other activity. When notifications can’t be delivered instantly, multiple notifications may be coalesced.
You must retain the returned token for as long as you want updates to be sent to the block. To stop receiving updates, call
invalidate()
on the token.Declaration
Swift
public func observe(_ block: @escaping NotificationBlock) -> NotificationToken
Parameters
block
A block which is called to process Realm notifications. It receives the following parameters:
notification
: the incoming notification;realm
: the Realm for which the notification occurred.Return Value
A token which must be held for as long as you wish to continue receiving change notifications.
-
Set this property to
true
to automatically update this Realm when changes happen in other threads.If set to
true
(the default), changes made on other threads will be reflected in this Realm on the next cycle of the run loop after the changes are committed. If set tofalse
, you must manually callrefresh()
on the Realm to update it to get the latest data.Note that by default, background threads do not have an active run loop and you will need to manually call
refresh()
in order to update to the latest version, even ifautorefresh
is set totrue
.Even with this property enabled, you can still call
refresh()
at any time to update the Realm before the automatic refresh would occur.Notifications are sent when a write transaction is committed whether or not automatic refreshing is enabled.
Disabling
autorefresh
on aRealm
without any strong references to it will not have any effect, andautorefresh
will revert back totrue
the next time the Realm is created. This is normally irrelevant as it means that there is nothing to refresh (as managedObject
s,List
s, andResults
have strong references to theRealm
that manages them), but it means that settingautorefresh = false
inapplication(_:didFinishLaunchingWithOptions:)
and only later storing Realm objects will not work.Defaults to
true
.Declaration
Swift
public var autorefresh: Bool { get nonmutating set }
-
Updates the Realm and outstanding objects managed by the Realm to point to the most recent data.
Declaration
Swift
@discardableResult public func refresh() -> Bool
Return Value
Whether there were any updates for the Realm. Note that
true
may be returned even if no data actually changed.
-
Returns if this Realm is frozen.
Declaration
Swift
public var isFrozen: Bool { get }
-
Returns a frozen (immutable) snapshot of this Realm.
A frozen Realm is an immutable snapshot view of a particular version of a Realm’s data. Unlike normal Realm instances, it does not live-update to reflect writes made to the Realm, and can be accessed from any thread. Writing to a frozen Realm is not allowed, and attempting to begin a write transaction will throw an exception.
All objects and collections read from a frozen Realm will also be frozen.
Warning
Holding onto a frozen Realm for an extended period while performing write transaction on the Realm may result in the Realm file growing to large sizes. SeeRealm.Configuration.maximumNumberOfActiveVersions
for more information.Declaration
Swift
public func freeze() -> Realm
-
Returns a frozen (immutable) snapshot of the given object.
The frozen copy is an immutable object which contains the same data as the given object currently contains, but will not update when writes are made to the containing Realm. Unlike live objects, frozen objects can be accessed from any thread.
Warning
Holding onto a frozen object for an extended period while performing write transaction on the Realm may result in the Realm file growing to large sizes. SeeRealm.Configuration.maximumNumberOfActiveVersions
for more information.Declaration
Swift
public func freeze<T>(_ obj: T) -> T where T : Object
-
Returns a frozen (immutable) snapshot of the given collection.
The frozen copy is an immutable collection which contains the same data as the given collection currently contains, but will not update when writes are made to the containing Realm. Unlike live collections, frozen collections can be accessed from any thread.
Warning
This method cannot be called during a write transaction, or when the Realm is read-only.Warning
Holding onto a frozen collection for an extended period while performing write transaction on the Realm may result in the Realm file growing to large sizes. SeeRealm.Configuration.maximumNumberOfActiveVersions
for more information.Declaration
Swift
public func freeze<Collection>(_ collection: Collection) -> Collection where Collection : RealmCollection
-
Invalidates all
Object
s,Results
,LinkingObjects
, andList
s managed by the Realm.A Realm holds a read lock on the version of the data accessed by it, so that changes made to the Realm on different threads do not modify or delete the data seen by this Realm. Calling this method releases the read lock, allowing the space used on disk to be reused by later write transactions rather than growing the file. This method should be called before performing long blocking operations on a background thread on which you previously read data from the Realm which you no longer need.
All
Object
,Results
andList
instances obtained from thisRealm
instance on the current thread are invalidated.Object
s andArray
s cannot be used.Results
will become empty. The Realm itself remains valid, and a new read transaction is implicitly begun the next time data is read from the Realm.Calling this method multiple times in a row without reading any data from the Realm, or before ever reading any data from the Realm, is a no-op. This method may not be called on a read-only Realm.
Declaration
Swift
public func invalidate()
-
Writes a compacted and optionally encrypted copy of the Realm to the given local URL.
The destination file cannot already exist.
Note that if this method is called from within a write transaction, the current data is written, not the data from the point when the previous write transaction was committed.
Throws
An
NSError
if the copy could not be written.Declaration
Swift
public func writeCopy(toFile fileURL: URL, encryptionKey: Data? = nil) throws
Parameters
fileURL
Local URL to save the Realm to.
encryptionKey
Optional 64-byte encryption key to encrypt the new file with.
-
Checks if the Realm file for the given configuration exists locally on disk.
For non-synchronized, non-in-memory Realms, this is equivalent to
FileManager.default.fileExists(atPath:)
. For synchronized Realms, it takes care of computing the actual path on disk based on the server, virtual path, and user as is done when opening the Realm.@param config A Realm configuration to check the existence of. @return true if the Realm file for the given configuration exists on disk, false otherwise.
Declaration
Swift
public static func fileExists(for config: Configuration) -> Bool
-
Deletes the local Realm file and associated temporary files for the given configuration.
This deletes the
.realm
,.note
and.management
files which would be created by opening the Realm with the given configuration. It does not delete the.lock
file (which contains no persisted data and is recreated from scratch every time the Realm file is opened).The Realm must not be currently open on any thread or in another process. If it is, this will throw the error .alreadyOpen. Attempting to open the Realm on another thread while the deletion is happening will block, and then create a new Realm and open that afterwards.
If the Realm already does not exist this will return
false
.@param config A Realm configuration identifying the Realm to be deleted. @return true if any files were deleted, false otherwise.
Declaration
Swift
public static func deleteFiles(for config: Configuration) throws -> Bool
-
Struct that describes the error codes within the Realm error domain. The values can be used to catch a variety of recoverable errors, especially those happening when initializing a Realm instance.
See morelet realm: Realm? do { realm = try Realm() } catch Realm.Error.incompatibleLockFile { print("Realm Browser app may be attached to Realm on device?") }
Declaration
Swift
public struct Error
-
Performs the given Realm configuration’s migration block on a Realm at the given path.
This method is called automatically when opening a Realm for the first time and does not need to be called explicitly. You can choose to call this method to control exactly when and how migrations are performed.
Declaration
Swift
public static func performMigration(for configuration: Realm.Configuration = Realm.Configuration.defaultConfiguration) throws
Parameters
configuration
The Realm configuration used to open and migrate the Realm.
-
Returns whether two
Realm
instances are equal.Declaration
Swift
public static func == (lhs: Realm, rhs: Realm) -> Bool
-
A notification indicating that changes were made to a Realm.
See moreDeclaration
Swift
public enum Notification : String
-
A
Configuration
instance describes the different options used to create an instance of a Realm.Configuration
instances are just plain Swift structs. UnlikeRealm
s andObject
s, they can be freely shared between threads as long as you do not mutate them.Creating configuration values for class subsets (by setting the
See moreobjectClasses
property) can be expensive. Because of this, you will normally want to cache and reuse a single configuration value for each distinct configuration rather than creating a new value each time you open a Realm.Declaration
Swift
public struct Configuration
-
Get the SyncSession used by this Realm. Will be nil if this is not a synchronized Realm.
Declaration
Swift
public var syncSession: SyncSession? { get }
-
Returns the computed privileges which the current user has for this Realm.
This combines all privileges granted on the Realm by all Roles which the current User is a member of into the final privileges which will be enforced by the server.
The privilege calculation is done locally using cached data, and inherently may be stale. It is possible that this method may indicate that an operation is permitted but the server will still reject it if permission is revoked before the changes have been integrated on the server.
Non-synchronized and fully-synchronized Realms always have permission to perform all operations.
Declaration
Swift
public func getPrivileges() -> RealmPrivileges
Return Value
The privileges which the current user has for the current Realm.
-
Returns the computed privileges which the current user has for the given object.
This combines all privileges granted on the object by all Roles which the current User is a member of into the final privileges which will be enforced by the server.
The privilege calculation is done locally using cached data, and inherently may be stale. It is possible that this method may indicate that an operation is permitted but the server will still reject it if permission is revoked before the changes have been integrated on the server.
Non-synchronized and fully-synchronized Realms always have permission to perform all operations.
The object must be a valid object managed by this Realm. Passing in an invalidated object, an unmanaged object, or an object managed by a different Realm will throw an exception.
Declaration
Swift
public func getPrivileges(_ object: Object) -> ObjectPrivileges
Parameters
object
A managed object to get the privileges for.
Return Value
The privileges which the current user has for the given object.
-
Returns the computed privileges which the current user has for the given class.
This combines all privileges granted on the class by all Roles which the current User is a member of into the final privileges which will be enforced by the server.
The privilege calculation is done locally using cached data, and inherently may be stale. It is possible that this method may indicate that an operation is permitted but the server will still reject it if permission is revoked before the changes have been integrated on the server.
Non-synchronized and fully-synchronized Realms always have permission to perform all operations.
Declaration
Swift
public func getPrivileges<T>(_ cls: T.Type) -> ClassPrivileges where T : Object
Parameters
cls
An Object subclass to get the privileges for.
Return Value
The privileges which the current user has for the given class.
-
Returns the computed privileges which the current user has for the named class.
This combines all privileges granted on the class by all Roles which the current User is a member of into the final privileges which will be enforced by the server.
The privilege calculation is done locally using cached data, and inherently may be stale. It is possible that this method may indicate that an operation is permitted but the server will still reject it if permission is revoked before the changes have been integrated on the server.
Non-synchronized and fully-synchronized Realms always have permission to perform all operations.
Declaration
Swift
public func getPrivileges(forClassNamed className: String) -> ClassPrivileges
Parameters
className
The name of an Object subclass to get the privileges for.
Return Value
The privileges which the current user has for the named class.
-
Returns the class-wide permissions for the given class.
Requires
This must only be called on a Realm using query-based sync.Declaration
Swift
public func permissions<T>(forType cls: T.Type) -> List<Permission> where T : Object
Parameters
cls
An Object subclass to get the permissions for.
Return Value
The class-wide permissions for the given class.
-
Returns the class-wide permissions for the named class.
Requires
className must name a class in this Realm’s schema.Requires
This must only be called on a Realm using query-based sync.Declaration
Swift
public func permissions(forClassNamed className: String) -> List<Permission>
Parameters
cls
The name of an Object subclass to get the permissions for.
Return Value
The class-wide permissions for the named class.
-
Returns the Realm-wide permissions.
Requires
This must only be called on a Realm using query-based sync.Declaration
Swift
public var permissions: List<Permission> { get }
-
Returns this list of the query-based sync subscriptions made for this Realm.
This list includes all subscriptions which are currently in the states
.pending
,.created
, and.error
. Newly created subscriptions which are still in the.creating
state are not included, and calling this immediately after callingResults.subscribe()
will typically not include that subscription. Similarly, because unsubscription happens asynchronously, this may continue to include subscriptions afterSyncSubscription.unsubscribe()
is called on them.Requires
This must only be called on a Realm using query-based sync.Declaration
Swift
public func subscriptions() -> Results<SyncSubscription>
-
Returns the named query-based sync subscription, if it exists.
Subscriptions are created asynchronously, so calling this immediately after calling Results.subscribe(named:)
will typically return
nil. Only subscriptions which are currently in the states
.pending,
.created, and
.error` can be retrieved with this method.Requires
This must only be called on a Realm using query-based sync.Declaration
Swift
public func subscription(named: String) -> SyncSubscription?
-
Returns the same object as the one referenced when the
ThreadSafeReference
was first created, but resolved for the current Realm for this thread. Returnsnil
if this object was deleted after the reference was created.Warning
A
ThreadSafeReference
object must be resolved at most once. Failing to resolve aThreadSafeReference
will result in the source version of the Realm being pinned until the reference is deallocated. An exception will be thrown if a reference is resolved more than once.Warning
Cannot call within a write transaction.
Note
Will refresh this Realm if the source Realm was at a later version than this one.
See
ThreadSafeReference(to:)
Declaration
Swift
public func resolve<Confined>(_ reference: ThreadSafeReference<Confined>) -> Confined? where Confined : ThreadConfined
Parameters
reference
The thread-safe reference to the thread-confined object to resolve in this Realm.