Inherits from NSObject
Declared in RLMObject.h
RLMObject.mm

Overview

In Realm you define your model classes by subclassing RLMObject and adding properties to be persisted. You then instantiate and use your custom subclasses instead of using the RLMObject class directly.

 // Dog.h
 @interface Dog : RLMObject
 @property NSString *name;
 @property BOOL      adopted;
 @end

 // Dog.m
 @implementation Dog
 @end //none needed

Supported property types

  • NSString
  • NSInteger, CGFloat, int, long, float, and double
  • BOOL or bool
  • NSDate
  • NSData
  • RLMObject subclasses, so you can have many-to-one relationships.
  • RLMArray<X>, where X is an RLMObject subclass, so you can have many-to-many relationships.

Attributes for Properties

You can set which of these properties should be indexed, stored inline, unique, required as well as delete rules for the links by implementing the attributesForProperty: method.

You can set properties to ignore (i.e. transient properties you do not want persisted to a Realm) by implementing ignoredProperties.

You can set default values for properties by implementing defaultPropertyValues.

Querying

You can query an object directly via the class methods: allObjects, objectsWhere:, objectsOrderedBy:where: and objectForKeyedSubscript: These methods allow you to easily query a custom subclass for instances of this class in the default Realm. To search in a Realm other than the default Realm use the interface on an RLMRealm instance.

Relationships

See our Cocoa guide for more details.

Tasks

Creating & Initializing Objects

Customizing your Objects

Getting & Querying Objects from the Default Realm

Querying Specific Realms

Serializing Objects to JSON

Properties

deletedFromRealm

Indicates if an object has been deleted from a Realm and can no longer be accessed.

@property (nonatomic, readonly, getter=isDeletedFromRealm) BOOL deletedFromRealm

Declared In

RLMObject.h

objectSchema

The ObjectSchema which lists the persisted properties for this object.

@property (nonatomic, readonly) RLMObjectSchema *objectSchema

Declared In

RLMObject.h

realm

The Realm in which this object is persisted. Returns nil for standalone objects.

@property (nonatomic, readonly) RLMRealm *realm

Declared In

RLMObject.h

Class Methods

allObjects

Get all objects of this type from the default Realm.

+ (RLMArray *)allObjects

Return Value

An RLMArray of all objects of this type in the default Realm.

Declared In

RLMObject.h

allObjectsInRealm:

Get all objects of this type from the specified Realm.

+ (RLMArray *)allObjectsInRealm:(RLMRealm *)realm

Parameters

realm

The Realm instance to query.

Return Value

An RLMArray of all objects of this type in the specified Realm.

Declared In

RLMObject.h

attributesForProperty:

Implement to set custom attributes for each property.

+ (RLMPropertyAttributes)attributesForProperty:(NSString *)propertyName

Parameters

propertyName

Name of property for which attributes have been requested.

Return Value

Bitmask of property attributes for the given property.

Discussion

The default attributes for each property should be obtained by calling [super attributesForProperty:propertyName], and then ORed together with the attributes you wish to add. For example, to index a single property:

 @interface Model : RLMObject
 @property NSString *indexedProperty;
 @property NSString *unindexedProperty;
 @end

 @implementation Model
 + (RLMPropertyAttributes)attributesForProperty:(NSString *)propertyName {
    RLMPropertyAttributes attributes = [super attributesForProperty:propertyName];
    if ([propertyName isEqualToString:@"indexedProperty"]) {
        attributes |= RLMPropertyAttributeIndexed;
    }
    return attributes;
 }
 @end

Declared In

RLMObject.h

className

Helper to return the class name for an RLMObject subclass.

+ (NSString *)className

Return Value

The class name for the model class.

Declared In

RLMObject.h

createInDefaultRealmWithObject:

Create an RLMObject in the default Realm with a a given object.

+ (instancetype)createInDefaultRealmWithObject:(id)object

Parameters

object

The object used to populate the object. This can be any key/value compliant object, or a JSON object such as those returned from the methods in NSJSONSerialization, or an NSArray with one object for each persisted property. An exception will be thrown if all required properties are not present or no default is provided.

When passing in an NSArray, all properties must be present, valid and in the same order as the properties defined in the model.

Discussion

Creates an instance of this object and adds it to the default Realm populating the object with the given object.

See Also

Declared In

RLMObject.h

createInRealm:withObject:

Create an RLMObject in a Realm with a given object.

+ (instancetype)createInRealm:(RLMRealm *)realm withObject:(id)object

Parameters

realm

The Realm in which this object is persisted.

object

The object used to populate the object. This can be any key/value compliant object, or a JSON object such as those returned from the methods in NSJSONSerialization, or an NSArray with one object for each persisted property. An exception will be thrown if all required properties are not present or no default is provided.

            When passing in an NSArray, all properties must be present, valid and in the same order as the properties defined in the model.

Discussion

Creates an instance of this object and adds it to the given Realm populating the object with the given object.

See Also

Declared In

RLMObject.h

createOrUpdateInDefaultRealmWithObject:

Create or update an RLMObject in the default Realm with a a given object.

+ (instancetype)createOrUpdateInDefaultRealmWithObject:(id)object

Parameters

object

The object used to populate the object. This can be any key/value compliant object, or a JSON object such as those returned from the methods in NSJSONSerialization, or an NSArray with one object for each persisted property. An exception will be thrown if all required properties are not present or no default is provided.

When passing in an NSArray, all properties must be present, valid and in the same order as the properties defined in the model.

Discussion

This method can only be called on object types with a primary key defined. If there is already an object with the same primary key value in the default RLMRealm its values are updated and the object is returned. Otherwise this creates and populates a new instance of this object in the default Realm.

See Also

Declared In

RLMObject.h

createOrUpdateInRealm:withObject:

Create or update an RLMObject with a a given object.

+ (instancetype)createOrUpdateInRealm:(RLMRealm *)realm withObject:(id)object

Parameters

realm

The Realm in which this object is persisted.

object

The object used to populate the object. This can be any key/value compliant object, or a JSON object such as those returned from the methods in NSJSONSerialization, or an NSArray with one object for each persisted property. An exception will be thrown if all required properties are not present or no default is provided.

When passing in an NSArray, all properties must be present, valid and in the same order as the properties defined in the model.

Discussion

This method can only be called on object types with a primary key defined. If there is already an object with the same primary key value in the provided RLMRealm its values are updated and the object is returned. Otherwise this creates and populates a new instance of this object in the provided Realm.

See Also

Declared In

RLMObject.h

defaultPropertyValues

Implement to indicate the default values to be used for each property.

+ (NSDictionary *)defaultPropertyValues

Return Value

NSDictionary mapping property names to their default values.

Declared In

RLMObject.h

ignoredProperties

Implement to return an array of property names to ignore. These properties will not be persisted and are treated as transient.

+ (NSArray *)ignoredProperties

Return Value

NSArray of property names to ignore.

Declared In

RLMObject.h

objectForPrimaryKey:

Get the single object with the given primary key from the default Realm.

+ (instancetype)objectForPrimaryKey:(id)primaryKey

Return Value

An object of the subclass type or nil if an object with the given primary key does not exist.

Discussion

Returns the object from the default Realm which has the given primary key, or nil if the object does not exist. This is slightly faster than the otherwise equivalent [[SubclassName objectsWhere:@"primaryKeyPropertyName = %@", key] firstObject].

This method requires that primaryKey be overridden on the receiving subclass.

See Also

Declared In

RLMObject.h

objectInRealm:forPrimaryKey:

Get the single object with the given primary key from the specified Realm.

+ (instancetype)objectInRealm:(RLMRealm *)realm forPrimaryKey:(id)primaryKey

Return Value

An object of the subclass type or nil if an object with the given primary key does not exist.

Discussion

Returns the object from the specified Realm which has the given primary key, or nil if the object does not exist. This is slightly faster than the otherwise equivalent [[SubclassName objectsInRealm:realm where:@"primaryKeyPropertyName = %@", key] firstObject].

This method requires that primaryKey be overridden on the receiving subclass.

See Also

Declared In

RLMObject.h

objectsInRealm:where:

Get objects matching the given predicate for this type from the specified Realm.

+ (RLMArray *)objectsInRealm:(RLMRealm *)realm where:(NSString *)predicateFormat, ...

Parameters

realm

The Realm instance to query.

predicateFormat

The predicate format string which can accept variable arguments.

Return Value

An RLMArray of objects of the subclass type in the specified Realm that match the given predicate

Declared In

RLMObject.h

objectsInRealm:withPredicate:

Get objects matching the given predicate for this type from the specified Realm.

+ (RLMArray *)objectsInRealm:(RLMRealm *)realm withPredicate:(NSPredicate *)predicate

Parameters

realm

The Realm instance to query.

predicate

The predicate to filter the objects.

Return Value

An RLMArray of objects of the subclass type in the specified Realm that match the given predicate

Declared In

RLMObject.h

objectsWhere:

Get objects matching the given predicate for this type from the default Realm.

+ (RLMArray *)objectsWhere:(NSString *)predicateFormat, ...

Parameters

predicateFormat

The predicate format string which can accept variable arguments.

Return Value

An RLMArray of objects of the subclass type in the default Realm that match the given predicate

Declared In

RLMObject.h

objectsWithPredicate:

Get objects matching the given predicate for this type from the default Realm.

+ (RLMArray *)objectsWithPredicate:(NSPredicate *)predicate

Parameters

predicate

The predicate to filter the objects.

Return Value

An RLMArray of objects of the subclass type in the default Realm that match the given predicate

Declared In

RLMObject.h

primaryKey

Implement to designate a property as the primary key for a RLMObject subclass. Only properties of type RLMPropertyTypeString and RLMPropertyTypeInt can be designated as the primary key. Primary key properties enforce uniqueness for each value whenever the property is set which incurs some overhead.

+ (NSString *)primaryKey

Return Value

Name of the property designated as the primary key.

Declared In

RLMObject.h

Instance Methods

JSONString

Returns this object represented as a JSON string.

- (NSString *)JSONString

Return Value

JSON string representation of this object.

Declared In

RLMObject.h

init

Initialize a standalone RLMObject

- (instancetype)init

Discussion

Initialize an unpersisted instance of this object. Call addObject: on an RLMRealm to add standalone object to a realm.

See Also

Declared In

RLMObject.h

initWithObject:

Initialize a standalone RLMObject with values from an NSArray or NSDictionary

- (instancetype)initWithObject:(id)object

Discussion

Initialize an unpersisted instance of this object. Call addObject: on an RLMRealm to add standalone object to a realm.

See Also

Declared In

RLMObject.h

isEqualToObject:

Returns YES if another RLMObject points to the same object in a RLMRealm. For RLMObject types with a primary, key, isEqual: is overridden to use this method (along with a corresponding implementation for hash.

- (BOOL)isEqualToObject:(RLMObject *)object

Parameters

object

The object to compare to.

Return Value

YES if the object represents the same object in the same RLMRealm.

Declared In

RLMObject.h