Realm/Swift: compilation error: Missing argument for parameter 'forPrimaryKey' in call - swift

Question

I'm trying to get my head around swift & realm, so I've created some kind of a test pad programme.
My model is defined like so
class RealmRecord: Object {
// properties
dynamic var id: Int = 0;
dynamic var text: String = ""
dynamic var var1: Double = 0.0
dynamic var var2: Int = 0
dynamic var var3: Double = 0.0
dynamic var var4: Int = 0
dynamic var cdate: Date = Date()
dynamic var cusr: String = ""
dynamic var mdate: Date = Date.distantPast
dynamic var musr: String = ""
dynamic var mcnt: Int = 0
// methods
convenience init(id: Int? = 0, text: String? = "", var1: Double? = 0.0,
var2: Int? = 0, var3: Double? = 0.0, var4: Int? = 0,
cusr: String? = "") {
self.init()
self.id = id!
self.text = text!
self.var1 = var1!
self.var2 = var2!
self.var3 = var3!
self.var4 = var4!
self.cdate = Date()
self.cusr = cusr!
self.mdate = Date.distantPast
self.musr = ""
self.mcnt = 0
} // init
override static func primaryKey() -> String? {
return "id"
} // primaryKey
} // RealmRecord
Persisting the data is accomplished by
try recRealm?.write {
recRealm?.add(self.rec, update: true)
} // try
But when adding the data retrieval via
if let inrec = self.recRealm?.object(RealmRecord.self) {
return inrec
} else {
return List<RealmRecord>()
} // if/else
I'm receiving an error message while compiling the code, reading
DataRealmRecord.swift:84:39: Missing argument for parameter 'forPrimaryKey' in call
Looking at the Realm documentation reveals only retrieving all persisted data--apparently without having a primary key defined--, or, alternatively, a single object, specified by the primary key.
Sifting through The Net brings up pretty much the same.
Given the model above, how can I retrieve all persisted data?
-- Sil68
EDIT
I've also defined a class facilitating this Realm model of mine, which basically carries out the following steps:
generate some random data;
persist data via the Realm model;
read data in again;
compare generated with read data.
The code
import Foundation
import RealmSwift
class DataRealmRecord {
// properties
private(set) var recDBPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first!
private(set) var recDBSubPath = "Persistency"
private(set) var recDBFile = "data.realm"
private(set) var recRealm: Realm?
private(set) var recRealmCfg: Realm.Configuration?
private(set) var rec = List<RealmRecord>()
private(set) var startTime = 0.0
private(set) var stopTime = 0.0
private(set) var runTime = 0.0
private(set) var outLog = ""
private(set) var realmOk = false
// methods
init() {
// assemble destination folder/database name
do {
try FileManager.default.createDirectory(atPath: recDBPath + "/" +
recDBSubPath,
withIntermediateDirectories: true,
attributes: nil)
recDBFile = recDBPath + "/" + recDBSubPath + "/" + recDBFile
realmOk = true
} catch let error as NSError {
outLog += error.localizedDescription
realmOk = false
} // do/try/catch
// configure realm database
if (realmOk) {
self.recRealmCfg = Realm.Configuration(fileURL: Foundation.URL(string: self.recDBFile))
do {
self.recRealm = try Realm(configuration: self.recRealmCfg!)
realmOk = true
} catch let error as NSError {
outLog += error.localizedDescription
realmOk = false
} // do/try/catch
} // if
} // init
// generate test data
func generateData(noRecs: Int? = 1000, simDat: SimulateData?) {
for i in 1...noRecs! {
let realmRec = RealmRecord(id: i,
text: String(format: "Record #%04d", i),
var1: simDat?.datnorm[i - 1] ?? 1.1,
var2: simDat?.datpois[i - 1] ?? 2,
var3: simDat?.datunif[i - 1] ?? 3.3,
var4: simDat?.datbern[i - 1] ?? 4,
cusr: "me")
self.rec.append(realmRec)
} // for
} // generateData
// retrieve test data from persistent storage
func loadData() -> List<RealmRecord> {
if let inrec = self.recRealm?.object(RealmRecord.self) {
return inrec
} else {
return List<RealmRecord>()
} // if/else
} // loadData
// save test data to persistent storage
func saveData() {
do {
try recRealm?.write {
recRealm?.add(self.rec, update: true)
} // try
} catch let error as NSError {
outLog += error.localizedDescription
} // do/try/catch
} // saveData
// compare two data sets
func compareData(rec1: List<RealmRecord>, rec2: List<RealmRecord>) -> Bool {
var rc = false
if rec1.count == rec2.count {
rc = true
for i in 0..<rec1.count {
rc = rc && (rec1[i] == rec2[i])
} // for
} // if
return rc
} // compareData
// run a full evaluation cycle
// (1) generate test data;
// (2) save test data to persistant storage;
// (3) retrieve test data from persistant storage;
// (4) compare generated data with retrieved data.
func fullCycle(noRecs: Int? = 1000, simDat: SimulateData?, prnData: Bool? = false) {
// start execution time measurement
self.startTime = Double(CFAbsoluteTimeGetCurrent())
// execute the full cycle
self.generateData(noRecs: noRecs, simDat: simDat) // (1)
self.saveData() // (2)
let rec2 = self.loadData() // (3)
let cmpRec = compareData(rec1: self.rec, rec2: rec2) // (4)
// stop execution time measurement & calculate elapsed time
self.stopTime = Double(CFAbsoluteTimeGetCurrent())
self.runTime = self.stopTime - self.startTime
} // fullCycle
} // DataRealmRecord
Issue at hand is, this code fails to compile due to the error message mentioned above (in method loadData()).

Answer 1

The Swift compiler is telling you that it thinks you're trying to call Realm.object(ofType:forPrimaryKey:), which retrieves a single object based on the value of its primary key. It sounds like you really want to call Realm.objects(_:) to retrieve all objects of a given type. Note that this returns a Results<T>, not a List<T>.