I have 2 classes: Company and Employee. Both inherit the Realm Object class.
class Company:Object {
var name:String = ""
var employee:Employee?
override static func primaryKey() -> String? {
return "name"
}
}
class Employee:Object {
var name:String = ""
var age:Int = 0
override static func primaryKey() -> String? {
return "name"
}
}
Populate the objects
var emp = Employee()
emp.name = "Sachin"
emp.age = 35
var comp = Company()
comp.name = "BCCI"
comp.employee = emp
println("Before: \(comp.employee)")
var realm = Realm()
realm.write {
println("Before Add: \(comp.employee)")
realm.add(comp, update: true)
println("In Block: \(comp.employee)")
}
println("After: \(comp.employee)")
RESULT:
Before: Employee {
name = Sachin;
age = 35;
}
Before Add: Employee {
name = Sachin;
age = 35;
}
In Block: nil
After: nil
QUESTION:
Why is the employee property of the Company object nil after the realm.add() operation? Any thoughts?
For all Realm Swift properties (except for List), you need to declare the properties as dynamic. Changing your model definitions to the following should help!
class Company:Object {
dynamic var name:String = ""
dynamic var employee:Employee?
override static func primaryKey() -> String? {
return "name"
}
}
class Employee:Object {
dynamic var name:String = ""
dynamic var age:Int = 0
override static func primaryKey() -> String? {
return "name"
}
}
Related
I'm making an app for airports and I'm getting an array of data from one api, like so:
"data":[
{"id":"001","code":"ABZ","name":"Aberdeen","country":"United Kingdom"},
{"id":"002","code":"AUH","name":"Abu Dhabi","country":"United Arab Emirates"},
.
.
.
]
AND :
"airports":[
{"from":"001",
"to":["1","3","11","13","12","20","23","27","29","31","33"]
},
.
.
.
]
I have created realm model classes:
class AirportsDataRealm: Object {
#objc dynamic var name: String = ""
#objc dynamic var id: Int = 0
#objc dynamic var code: String = ""
#objc dynamic var country: String = ""
override static func primaryKey() -> String? {
return "id"
}
}
class AirportsFromToRealm: Object {
#objc dynamic var fromID: Int = 0
var toID = List<Int>()
override static func primaryKey() -> String? {
return "fromID"
}
}
now I want to save it into realm, I'm using swiftyJSON and I have used for-loop to do it and it is working fine but I think it's taking long time since the array is very long, here is what I've done:
// Airports Data
let countData = json["data"].count
for i in 0...countData - 1{
let airportsDataModel = AirportsDataRealm()
airportsDataModel.code = json["data"][i]["code"].stringValue
airportsDataModel.name = json["data"][i]["name"].stringValue
airportsDataModel.country = json["data"][i]["country"].stringValue
airportsDataModel.id = Int(json["data"][i]["id"].stringValue)!
try! realm.write {
realm.add(airportsDataModel, update: true)
}
}
//Airports FROM-TO
let countFromTo = json["airports"].count
for i in 0...countFromTo - 1{
let fromToDataModel = AirportsFromToRealm()
fromToDataModel.fromID = Int(json["airports"][i]["from"].stringValue)!
let arrayTo = json["airports"][i]["to"].arrayValue.map{ $0.intValue }
fromToDataModel.toID.append(objectsIn: arrayTo)
try! realm.write {
realm.add(fromToDataModel, update: true)
}
}
is there any way to save the whole array in realm in one shot without for-loop?
P.S
"there should be a relation between the two tables because each from 'id' has a list of 'to' id's and the id's are from the data table, for now I managed to create this relations when fetching the data using filters ,, so just ignore this"
Thank you
Simply use map method,
First I needed to add initializers to my object classes and pass json array as a parameter, like so:
class AirportsDataRealm: Object {
#objc dynamic var name: String = ""
#objc dynamic var id: Int = 0
#objc dynamic var code: String = ""
#objc dynamic var country: String = ""
convenience required init(withJSON json : JSON) {
self.init()
self.name = json["name"].stringValue
self.id = json["id"].intValue
self.code = json["code"].stringValue
self.country = json["country"].stringValue
}
override static func primaryKey() -> String? {
return "id"
}
}
class AirportsFromToRealm: Object {
#objc dynamic var fromID: Int = 0
var toID = List<Int>()
convenience required init(withJSON json : JSON) {
self.init()
self.fromID = json["from"].intValue
let toArray = json["to"].arrayValue.map{ $0.intValue }
self.toID.append(objectsIn: toArray)
}
override static func primaryKey() -> String? {
return "fromID"
}
}
Then by using map method the code will look like this:
func updateAirport(json: JSON) {
// Airports Data
let airportsData : [AirportsDataRealm]
let airportsDataJsonArray = json["data"].array
airportsData = airportsDataJsonArray!.map{AirportsDataRealm(withJSON: $0)}
//Airports FROM-TO
let airportsFromTo : [AirportsFromToRealm]
let airportsFromToJsonArray = json["airports"].array
airportsFromTo = airportsFromToJsonArray!.map{AirportsFromToRealm(withJSON: $0)}
//Write To Realm
try! realm.write {
realm.add(airportsData, update: true)
realm.add(airportsFromTo, update: true)
}
}
No for loops anymore ^_^
I am facing an issue where I am unable to keep existing relationships after calling add(_, update: true) function.
I wrote a TaskSync class that is responsible for creating/updating Task objects:
class TaskSync: ISync {
typealias Model = Task
func sync(model: Task) {
let realm = try! Realm()
let inWrite = realm.isInWriteTransaction
if !inWrite {
realm.beginWrite()
}
let _task = realm.object(ofType: Task.self, forPrimaryKey: model.id)
// Persist matches as they are not getting fetched with the task
if let _task = _task {
print("matches: \(_task.matches.count)")
model.matches = _task.matches
}
realm.add(model, update: true)
if _task == nil {
var user = realm.object(ofType: User.self, forPrimaryKey: model.getUser().id)
if (user == nil) {
user = model.getUser()
realm.add(user!, update: true)
}
user!.tasks.append(model)
}
if !inWrite {
try! realm.commitWrite()
}
}
func sync(models: List<Task>) {
let realm = try! Realm()
try! realm.write {
models.forEach { task in
sync(model: task)
}
}
}
}
When a model is to be synced, I check if it already exists in the Realm and if so, I fetch it and try to include the matches property as this one is not included in the model.
Right before the call realm.add(model, update: true), model contains list of matches, however right after the realm.add is executed, the matches list is empty.
Here are the two models:
class Task: Object, ElementPreloadable, ElementImagePreloadable, ItemSectionable {
dynamic var id: Int = 0
dynamic var title: String = ""
dynamic var desc: String = ""
dynamic var price: Float = 0.0
dynamic var calculatedPrice: Float = 0.0
dynamic var location: String = ""
dynamic var duration: Int = 0
dynamic var date: String = ""
dynamic var category: Category?
dynamic var currency: Currency?
dynamic var longitude: Double = 0.0
dynamic var latitude: Double = 0.0
dynamic var state: Int = 0
dynamic var userId: Int = 0
// Existing images
var imagesExisting = List<URLImage>()
// New images
var imagesNew = List<Image>()
// Images deleted
var imagesDeleted = List<URLImage>()
private let users = LinkingObjects(fromType: User.self, property: "tasks")
var user: User?
var matches = List<Match>()
dynamic var notification: Notification?
override static func ignoredProperties() -> [String] {
return ["imagesExisting", "imagesNew", "imagesDeleted", "user", "tmpUser"]
}
override static func primaryKey() -> String? {
return "id"
}
func getImageMain() -> URLImage? {
for image in imagesExisting {
if image.main {
return image
}
}
return imagesExisting.first
}
func getSection() -> Int {
return state
}
func getSectionFieldName() -> String? {
return "state"
}
func getId() -> Int {
return id
}
func getURL() -> URL? {
if let image = getImageMain() {
return image.getResizedURL()
}
return nil
}
func getState() -> TaskOwnState {
return TaskOwnState(rawValue: state)!
}
func getUser() -> User {
return (user != nil ? user : users.first)!
}
}
class Match: Object, ElementPreloadable, ElementImagePreloadable, ItemSectionable {
dynamic var id: Int = 0
dynamic var state: Int = -1
dynamic var priorityOwnRaw: Int = 0
dynamic var priorityOtherRaw: Int = 0
dynamic var user: User!
var messages = List<Message>()
private let tasks = LinkingObjects(fromType: Task.self, property: "matches")
var task: Task?
dynamic var notification: Notification?
override static func primaryKey() -> String? {
return "id"
}
override static func ignoredProperties() -> [String] {
return ["task"]
}
func getId() -> Int {
return id
}
func getSection() -> Int {
return 0
}
func getURL() -> URL? {
if let image = user.getImageMain() {
return image.getResizedURL()
}
return nil
}
func getPriorityOwn() -> PriorityType {
if priorityOwnRaw == PriorityType.normal.rawValue {
return PriorityType.normal
}
else {
return PriorityType.favorite
}
}
func getPriorityOther() -> PriorityType {
if priorityOtherRaw == PriorityType.normal.rawValue {
return PriorityType.normal
}
else {
return PriorityType.favorite
}
}
func getSectionFieldName() -> String? {
return nil
}
func getTask() -> Task {
return (task != nil ? task : tasks.first)!
}
}
I spent hours trying to figure out why I am unable to keep the matches relationship when updating the task. Every advice will be highly appreciated!
This question was also asked upon Realm's GitHub issue tracker. For posterity, here is the solution.
List properties should always be declared as let properties, as assigning to them does not do anything useful. The correct way to copy all objects from one List to another is model.tasks.append(objectsIn: _user.tasks).
I'm trying to save my array of objects in Realm, but Realm appears to be saving only the last object.
This is my model class:
class ContactEntry: Entry {
dynamic var contactId: Int = 0
dynamic var email: String? = ""
dynamic var phone: String? = ""
dynamic var building: String? = ""
dynamic var room: String? = ""
dynamic var contactDescription: String? = ""
dynamic var worktime: String? = ""
dynamic var address: String? = ""
dynamic var personEntries: PersonEntry?
}
This is the base class:
class Entry: Object {
dynamic var id: Int = 0
override static func primaryKey() -> String? { return "id" }
}
This is code I'm using for saving:
func createOrUpdate(entities: [Entity]) {
let entries = toEntries(entities)
let realm = try! Realm()
try! realm.write {
realm.add(entries, update: true)
}
}
func toEntry(entity: Contact) -> ContactEntry {
let entry = ContactEntry()
entry.contactId = entity.id
entry.email = entity.email
entry.phone = entity.phone
entry.building = entity.building
entry.room = entity.room
entry.contactDescription = entity.description
entry.worktime = entity.worktime
entry.address = entity.address
entry.personEntries = personDAO.toEntry(entity.person)
return entry
}
func toEntry(entity: Person) -> PersonEntry {
let entry = PersonEntry()
entry.personId = entity.id
entry.firstname = entity.firstname
entry.middlename = entity.middlename
entry.lastname = entity.lastname
entry.photo = entity.photo
return entry
}
I think that it may be because I have relationship in my model, but I'm not sure why they'd be a problem.
I'm using them as described in the Realm documentation.
I have a database of tables Subject, Grade, Chapter and Question. A Subject has many Grade, a Grade and many Chapter, a Chapter has many Question. If I want to perform search all the questions of Subject = Biology, Grade = 4, Chapter = 1, how should I build the query?
My Classes
class Subject:Object {
dynamic var subject_id = 0
dynamic var subject_name = ""
let grades = List<Grade>()
override static func primaryKey() -> String? {
return "subject_id"
}
}
class Grade:Object {
dynamic var grade_id = 0
dynamic var grade_num = 0
let chapters = List<Chapter>()
override static func primaryKey() -> String? {
return "grade_id"
}
}
class Chapter:Object {
dynamic var chapter_id = 0
dynamic var chapter_num = 0
let questions = List<Question>()
override static func primaryKey() -> String? {
return "chapter_id"
}
}
class Question:Object {
dynamic var question_id = 0
dynamic var question_desc = ""
dynamic var question_ans = ""
override static func primaryKey() -> String? {
return "question_id"
}
}
So far the only way that I can think of to achieve this is as follows, which I feel that there are way to many nested loops and if else.
let realm = try! Realm()
let subjects = realm.objects(Subject).filter(NSPredicate(format: "subject_name = %#", "Biology"))
var searched:List<Question>?
for subject in subjects {
if subject.subject_name == "Biology" {
for grade in subject.grades {
if grade.grade_num == 4 {
for chapter in grade.chapters {
if chapter.chapter_num == 1 {
searched = chapter.questions
}
}
}
}
}
}
After Realm 0.100 it's possible to use inverse relationships in queries.
So, my suggestion would be to add inverse relationships to your model like this :
class Grade:Object {
dynamic var grade_id = 0
dynamic var grade_num = 0
let chapters = List<Chapter>()
let subjects = LinkingObjects(fromType: Subject.self, property: "grades")
override static func primaryKey() -> String? {
return "grade_id"
}
}
class Chapter:Object {
dynamic var subject_id = 0
dynamic var chapter_num = 0
let questions = List<Question>()
let grades = LinkingObjects(fromType: Grade.self, property: "chapters")
override static func primaryKey() -> String? {
return "subject_id"
}
}
class Question:Object {
dynamic var question_id = 0
dynamic var question_desc = ""
dynamic var question_ans = ""
let chapters = LinkingObjects(fromType: Chapter.self, property: "questions")
override static func primaryKey() -> String? {
return "question_id"
}
}
Then you can query your model similar to this:
let questionsIWant = realm.objects(Question.self)
.filter("ANY chapters.chapter_num == 3")
.filter("ANY chapters.grades.grade_num == 1")
.filter("ANY chapters.grades.subjects.subject_name == 'Biology'")
I've got an Article and a Category model linked by a many-to-one relationship. However, the Category model has a unique constraint on the id property because it's the primary key as you can see below.
class Article: Object
{
dynamic var id: String = ""
dynamic var title: String = ""
dynamic var category: Category()
override static func primaryKey() -> String? {
return "id"
}
}
class Category: Object
{
dynamic var id: String = ""
dynamic var title: String = ""
override static func primaryKey() -> String? {
return "id"
}
}
This will work until an Article got the same Category and throw an exception because of the unique constraint.
How am I supposed to implement this kind of relationship ? Is there any built-in way to persist only the Category id and retrieve the corresponding Category ?
Thanks
As you can read in Realm doc (0.92.1), you have to use a List<Object> for a many-to-one relationship.
See this link :
http://realm.io/docs/swift/latest/
class Dog: Object {
dynamic var name = ""
dynamic var owner: Person? // Can be optional
}
class Person: Object {
... // other property declarations
let dogs = List<Dog>()
}
let someDogs = Realm().objects(Dog).filter("name contains 'Fido'")
jim.dogs.extend(someDogs)
jim.dogs.append(rex)
So in your case, I guess it should be something like that :
class Article: Object
{
dynamic var id: String = ""
dynamic var title: String = ""
override static func primaryKey() -> String? {
return "id"
}
}
class Category: Object
{
dynamic var id: String = ""
dynamic var title: String = ""
dynamic var articles = List<Article>()
override static func primaryKey() -> String? {
return "id"
}
}
If your Realm version is older :
class Category: Object
{
...
dynamic var categories = RLMArray(objectClassName: Article.className())
}