until version 10.7.6 of Realm I could convert to dictionary and then to json with this code below, but the ListBase class no longer exists.
extension Object {
func toDictionary() -> NSDictionary {
let properties = self.objectSchema.properties.map { $0.name }
let dictionary = self.dictionaryWithValues(forKeys: properties)
let mutabledic = NSMutableDictionary()
mutabledic.setValuesForKeys(dictionary)
for prop in self.objectSchema.properties as [Property] {
// find lists
if let nestedObject = self[prop.name] as? Object {
mutabledic.setValue(nestedObject.toDictionary(), forKey: prop.name)
} else if let nestedListObject = self[prop.name] as? ListBase { /*Cannot find type 'ListBase' in scope*/
var objects = [AnyObject]()
for index in 0..<nestedListObject._rlmArray.count {
let object = nestedListObject._rlmArray[index] as! Object
objects.append(object.toDictionary())
}
mutabledic.setObject(objects, forKey: prop.name as NSCopying)
}
}
return mutabledic
}
}
let parameterDictionary = myRealmData.toDictionary()
guard let postData = try? JSONSerialization.data(withJSONObject: parameterDictionary, options: []) else {
return
}
List now inherits from RLMSwiftCollectionBase apparently, so you can check for that instead. Also, this is Swift. Use [String: Any] instead of NSDictionary.
extension Object {
func toDictionary() -> [String: Any] {
let properties = self.objectSchema.properties.map { $0.name }
var mutabledic = self.dictionaryWithValues(forKeys: properties)
for prop in self.objectSchema.properties as [Property] {
// find lists
if let nestedObject = self[prop.name] as? Object {
mutabledic[prop.name] = nestedObject.toDictionary()
} else if let nestedListObject = self[prop.name] as? RLMSwiftCollectionBase {
var objects = [[String: Any]]()
for index in 0..<nestedListObject._rlmCollection.count {
let object = nestedListObject._rlmCollection[index] as! Object
objects.append(object.toDictionary())
}
mutabledic[prop.name] = objects
}
}
return mutabledic
}
}
Thanks to #Eduardo Dos Santos. Just do the following steps. You will be good to go.
Change ListBase to RLMSwiftCollectionBase
Change _rlmArray to _rlmCollection
Import Realm
Related
How can I save my struct with NSCoding so that it doesn´t change even if the user
closes the app? I would appreciate it if you could also show me how to implement the missing code correctly.
UPDATE with two new functions below:
Here is my code:
struct RandomItems: Codable
{
var items : [String]
var seen = 0
init(items:[String], seen: Int)
{
self.items = items
self.seen = seen
}
init(_ items:[String])
{ self.init(items: items, seen: 0) }
mutating func next() -> String
{
let index = Int(arc4random_uniform(UInt32(items.count - seen)))
let item = items.remove(at:index)
items.append(item)
seen = (seen + 1) % items.count
return item
}
func toPropertyList() -> [String: Any] {
return [
"items": items,
"seen": seen
]
}
}
override func viewWillDisappear(_ animated: Bool) {
UserDefaults.standard.set(try? PropertyListEncoder().encode(quotes), forKey:"quote2")
}
override func viewDidAppear(_ animated: Bool) {
if let data = UserDefaults.standard.value(forKey:"quote2") as? Data {
let quote3 = try? PropertyListDecoder().decode(Array<RandomItems>.self, from: data)
}
}
}
extension QuotesViewController.RandomItems {
init?(propertyList: [String: Any]) {
return nil
}
}
How can I make sure the whole Array is covered here?
For structs you should be using the new Codable protocol. It is available since swift 4 and is highly recommended.
struct RandomItems: Codable
{
var items: [String]
var seen = 0
}
extension RandomItems {
init?(propertyList: [String: Any]) {
...
}
}
// Example usage
let a = RandomItems(items: ["hello"], seen: 2)
let data: Data = try! JSONEncoder().encode(a)
UserDefaults.standard.set(data, forKey: "MyKey") // Save data to disk
// some time passes
let data2: Data = UserDefaults.standard.data(forKey: "MyKey")! // fetch data from disk
let b = try! JSONDecoder().decode(RandomItems.self, from: data2)
Update
It looks like the Original Poster is nesting the struct inside of another class. Here is another example where there struct is nested.
class QuotesViewController: UIViewController {
struct RandomItems: Codable
{
var items: [String]
var seen = 0
}
}
extension QuotesViewController.RandomItems {
init(_ items:[String])
{ self.items = items }
init?(propertyList: [String: Any]) {
guard let items = propertyList["items"] as? [String] else { return nil }
guard let seen = propertyList["seen"] as? Int else { return nil }
self.items = items
self.seen = seen
}
}
// example usage
let a = QuotesViewController.RandomItems(items: ["hello"], seen: 2)
let data: Data = try! JSONEncoder().encode(a)
UserDefaults.standard.set(data, forKey: "MyKey") // Save data to disk
// some time passes
let data2: Data = UserDefaults.standard.data(forKey: "MyKey")! // fetch data from disk
let b = try! JSONDecoder().decode(QuotesViewController.RandomItems.self, from: data2)
I am trying to parse the emergency data in into emergency struct but it never statifies the condition and get into else case.Here is my code and structure.Some thing i have written woring in first line.
if let emergencyDict = snapshotValue["emergency"] as? [String:[String:Any]]{
for (emerId, emerData) in emergencyDict {
let emer = Emergency.init(emergency: emerData as NSDictionary)
emergency.append(emer)
}
}
else{
let emer = Emergency.init(emerg: "" as AnyObject)
emergency.append(emer)
}
struct Emergency{
var emer_id: String
var emer_name: String
var emer_phoneNo: String
init(emergency: NSDictionary) {
if emergency.object(forKey: "id") != nil {
emer_id = emergency.object(forKey: "id") as! String
}
else{
emer_id = ""
}
}
}
The problem you are having emergency as Array with type [Any] and if you remove the first object then you get Array of type [[String:Any]]. So try like this way.
if let array = snapshotValue["emergency"] as? [Any],
let emergencyArrar = Array(array.dropFirst()) as? [[String:Any]] {
print(emergencyArray)
for emergency in emergencyArray {
print(emergency)
}
}
You have written wrong in this line:
if let emergencyDict = snapshotValue["emergency"] as? [String:[String:Any]]{
It should be:
if let emergencyDict = snapshotValue["emergency"] as? [[String:Any]]{
This question should belong to query from firebase database.
// you have to get the children in emergency,
// then get the value(dictionary) of each child
ref.child("emergency").observeSingleEvent(of: .value, with: { (snapshot) in
let value = snapshot.value as? NSDictionary
let keys = value?.allKeys // [1, 2, 3 ....]
for key in keys {
ref.child("emergency").child(key)..observeSingleEvent(of: .value, with: { (snapshot) in
let value = snapshot.value as? NSDictionary
// Here is your dictionary
}
}
}) { (error) in
print(error.localizedDescription)
}
I have a Realm database called NewsCount. I need to download a new news only if there is a new news (respectively when newsCount change). And I make a comparison with the data parsing. But I can not compare them properly. How do you compare them?
Thi is my code
private func parseJSONData(_ data: Data) {
do {
let temp: NSString = NSString(data: data, encoding: String.Encoding.utf8.rawValue)!
let myNSData = temp.data(using: String.Encoding.utf8.rawValue)!
guard let jsonResult = try JSONSerialization.jsonObject(with: myNSData, options: JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary else {
return
}
guard let jsonNews = jsonResult["categories"] as? [AnyObject] else {
print("Empty array")
return
}
let realm = try Realm()
let category = realm.objects(NewsCount.self)
var array = [Int]()
for i in category {
array.append(i.newsCount)
}
print(array)
print("News COUNT2 \(category)")
for jsonnewes in jsonNews {
let newsJson = NewsCount()
//HERE I COMPARE
if !UserDefaults.standard.bool(forKey: "AppStarted") || jsonnewes["count"] as! Int > array[jsonnewes as! Int]{
newsJson.newsID = jsonnewes["term_id"] as! Int
newsJson.newsCount = jsonnewes["count"] as! Int
//print("News COUNT2 \(newsJson.newsCount)")
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "downloadNew"), object: nil)
} else {
newsJson.newsID = jsonnewes["term_id"] as! Int
newsJson.newsCount = jsonnewes["count"] as! Int
//print("News COUNT3 \(newsJson.newsCount)")
}
insertOrUpdate(newsJson)
}
} catch {
print(error)
}
}
Because Realm uses RealmOptional to use Int values you have to call the value atribute to the RealmOptional
Try change this:
for i in category {
array.append(i.newsCount.value)
}
First off, it's probably more appropriate to use Int(string) instead of as! Int force-casting to convert your JSON data to integers.
From the looks of it, jsonnewes is a dictionary full of JSON data, but you're casting it as an array index in array[jsonnewes as! Int] which (given array is an array and not a dictionary) shouldn't work.
Instead, in order to make sure you're explicitly retrieving the item you want, I'd recommend using Realm's primary key query method in order to retrieve the item you want.
let realm = try! Realm()
for newsItem in jsonNews {
let newsPrimaryKey = Int(newsItem)
let realmNews = realm.object(ofType: NewsCount.self, forPrimaryKey: newsPrimaryKey)
// Don't continue if a Realm object couldn't be found
guard let realmNews = realmNews else {
continue
}
// Perform comparison
if Int(newsItem["count"]) > realmNews.newsCount {
// Perform the update
}
}
I am trying to check the id of a record before I put it into the array, using xcode swift
here is the code. But, i get the following error
Notifications.swift:50:46: Cannot convert value of type 'String?!' to expected argument type 'Notifications'
on this line
*if (readRecordCoreData(result["MessageID"])==false)*
Please can some one help to explain this error
import CoreData
struct Notifications{
var NotifyID = [NSManagedObject]()
let MessageDesc: String
let Messageid: String
init(MessageDesc: String, Messageid:String) {
self.MessageDesc = MessageDesc
self.Messageid = Messageid
// self.MessageDate = MessageDate
}
static func MessagesWithJSON(results: NSArray) -> [Notifications] {
// Create an empty array of Albums to append to from this list
var Notification = [Notifications]()
// Store the results in our table data array
if results.count>0 {
for result in results {
//get fields from json
let Messageid = result["MessageID"] as! String
let MessageDesc = result["MessageDesc"] as? String
let newMessages = Notifications(MessageDesc: MessageDesc!, Messageid:Messageid)
//check with id's from core data
if (readRecordCoreData(result["MessageID"])==false)
{
Notification.append(newMessages)
}
}
}
return Notification
}
//check id
func readRecordCoreData(Jsonid: String) -> Bool {
var idStaus = false
let appDelegate =
UIApplication.sharedApplication().delegate as! AppDelegate
let managedContext = appDelegate.managedObjectContext
//2
let fetchRequest = NSFetchRequest(entityName: "ItemLog")
//3
do {
let resultsCD = try! managedContext.executeFetchRequest(fetchRequest)
if (resultsCD.count > 0) {
for i in 0 ..< resultsCD.count {
let match = resultsCD[i] as! NSManagedObject
let id = match.valueForKey("notificationID") as! String
if (Jsonid as String! == id)
{
idStaus = true
}
else{
idStaus = false
}
}
}
} catch let error as NSError {
print("Could not fetch \(error), \(error.userInfo)")
}
return idStaus
}
One of your methods is static and the other one is not :
func readRecordCoreData(Jsonid: String) -> Bool
static func MessagesWithJSON(results: NSArray) -> [Notifications]
Depending on what you want to accomplish you could declare both static, none, or replace
//check with id's from core data
if (readRecordCoreData(result["MessageID"])==false)
{
Notification.append(newMessages)
}
By
//check with id's from core data
if (Notifications.readRecordCoreData(Messageid)==false)
{
Notification.append(newMessages)
}
Not sure if the code will work past compilation however as there are many readability issues
I want to safely search through values in a swift Dictionary using if lets and making sure it is type safe as I get deeper and deeper into the dictionary. The dictionary contains dictionaries that contains NSArray that contains more dictionary.
At first attempt my code looks like this:
if let kkbox = ticket["KKBOX"] as? Dictionary<String, AnyObject> {
if let kkboxDlUrlDict = kkbox["kkbox_dl_url_list"] as? Dictionary<String, AnyObject> {
if let kkboxDlUrlArray = kkboxDlUrlDict["kkbox_dl_url"] as? NSArray {
for dict in kkboxDlUrlArray {
if let name = dict["name"] as? String {
if name == mediaType.rawValue {
urlStr = dict["url"] as String
}
}
}
} else { return nil }
} else { return nil }
} else { return nil }
How do I shorten it to perhaps one or 2 line?
I realised I can chain it if it is 2 layers. This works:
if let kkboxDlUrlArray = ticket["KKBOX"]?["kkbox_dl_url_list"] as? NSArray {
}
But any chain longer than that, will not compile.
Is there a way to chain through a dictionary more than once?
Thank you
You can chain, but with proper downcast at each step:
if let kkboxDlUrlArray = ((((ticket["KKBOX"] as? Dictionary<String, AnyObject>)?["kkbox_dl_url_list"]) as? Dictionary<String, AnyObject>)?["kkbox_dl_url"]) as? NSArray {
for dict in kkboxDlUrlArray {
println(dict)
}
}
That doesn't look good though - it's one line, but not readable.
Personally, without using any fancy functional way to do it, I would make the chain more explicit with just one optional binding:
let kkbox = ticket["KKBOX"] as? Dictionary<String, AnyObject>
let kkboxDlUrlDict = kkbox?["kkbox_dl_url_list"] as? Dictionary<String, AnyObject>
if let kkboxDlUrlArray = kkboxDlUrlDict?["kkbox_dl_url"] as? NSArray {
for dict in kkboxDlUrlArray {
println(dict)
}
}
In my opinion much easier to read, and with no unneeded indentation
Alternatively, you could use this extension, which mimics the original valueForKeyPath method that used to exist in NSDictionary but got axed for whatever reason:
Swift 4.1
extension Dictionary where Key: ExpressibleByStringLiteral {
func valueFor(keyPath: String) -> Any? {
var keys = keyPath.components(separatedBy: ".")
var val : Any = self
while keys.count > 0 {
if let key = keys[0] as? Key {
keys.remove(at: 0)
if let dic = val as? Dictionary<Key, Value> {
if let leaf = dic[key] {
val = leaf
} else {
return nil
}
} else {
return nil
}
} else {
return nil
}
}
return val
}
Your code would then read:
if let array = ticket.valueFor("KKBOX.kkbox_dl_url_list.kkbox_dl_url") as? [] {
// do something with array
}
Seems like swift 1.2 has added this feature.
"More powerful optional unwrapping with if let — The if let construct can now unwrap multiple optionals at once, as well as include intervening boolean conditions. This lets you express conditional control flow without unnecessary nesting."
https://developer.apple.com/swift/blog/