Can't pass value? (CoreData and API-call) - swift

Question

I have some trouble with part of my Swift Application. I am trying to make two requests to a REST API (Spark's API) and save the requested variables as CoreData. However, I can not get the values passed propably from one function to the other, even though it's all within the same class.
So here is how it should work.
The function startTimer calls a series of functions every 60 seconds.
var timer: dispatch_source_t!
//Calls the getData function twice every 60 seconds. First to get the Posturevalue and then to get the Time value.
func startTimer() {
let queue = dispatch_queue_create("que", nil)
timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue)
dispatch_source_set_timer(timer, DISPATCH_TIME_NOW, 60 * NSEC_PER_SEC, 1 * NSEC_PER_SEC)
dispatch_source_set_event_handler(timer) {
self.getData("Posturevalue")
let Posturevalue:Int = self.GSValHolder
self.getData("Time")
let Time:Int = self.GSValHolder
let CoreID:String = self.GSCoreID
self.saveCoreData(Time, PostureVal: Posturevalue, CoreID: CoreID)
}
dispatch_resume(timer)
}
First call is to the getData function, which sends an handles the JSON response. I know this is working, cause I can print the variables and call the set funtion.
//Sends a request to the URL to receive JSON data.
func getData(Variblename:String)
{
let dataurl:String = "https://api.spark.io/v1/devices/"+DeviceID+"/"+Variblename+"/?access_token="+Accesstoken
if let url = NSURL(string: dataurl) {
let request = NSURLRequest(URL: url)
initialiseTaskForGettingData(request, element: "results")
}
}
//Handles the JSON data. Get the DeviceID and Variblevalue (Posture Value and Time value)
func initialiseTaskForGettingData(request: NSURLRequest, element:String)
{
let task = session.dataTaskWithRequest(request) {data, response, downloadError in
if let error = downloadError
{
}
else
{
var parsingError: NSError?
let parsedResult: AnyObject! = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.AllowFragments, error: &parsingError)
if let coreData = parsedResult as? NSDictionary {
if let VariableVal = (coreData as NSDictionary)["result"] as? Int {
if let coreInfo = coreData["coreInfo"] as? NSDictionary {
if let deviceID = (coreInfo as NSDictionary)["deviceID"] as? String {
println(deviceID)
println(VariableVal)
self.GSValHolder = VariableVal
}
}
}
}
}
}
task.resume()
}
Then do I try to get the variable and assign it to a new variable. This part keep causing me trouble and won't work.
//Get/Set functions to pass AccessToken and CoreID from CoreInfoView to the Model.
var AccessToken:String!
var CoreID:String!
var GSAccessToken:String {
set (newAccessToken) {
self.AccessToken = newAccessToken
}
get {
return AccessToken
}
}
var GSCoreID:String {
set (newCoreID) {
self.CoreID = newCoreID
}
get {
return CoreID
}
}
var ValHolder:Int!
var GSValHolder:Int {
set (newVal) {
self.ValHolder = newVal
}
get {
return ValHolder
}
}
If it worked, the startTimer function would do the same over again in order to get the other variable. Finally I wan't to call the saveCoreData function and save the variables.
func saveCoreData(Time:Int, PostureVal:Int, CoreID:String) {
var appDel:AppDelegate = (UIApplication.sharedApplication().delegate as! AppDelegate)
var context:NSManagedObjectContext = appDel.managedObjectContext!
var request = NSFetchRequest(entityName: "Coredata")
var newCore = NSEntityDescription.insertNewObjectForEntityForName("Coredata", inManagedObjectContext: context) as! NSManagedObject
newCore.setValue(Time, forKey: "time")
newCore.setValue(PostureVal, forKey: "posturevalue")
context.save(nil)
println(newCore)
}
Hope it all makes sense and you are able to help me out.
Regards Mads R. Svendsen,
________________________________UPDATE_________________________________________
So I did a bit of reading and watched some tutorials on completionHandling and asynchronous, which helped a lot. My code now looks like this and works.
var timer: dispatch_source_t!
//Calls the getData function twice every 60 seconds. First to get the Posturevalue and then to get the Time value.
func startTimer() {
let queue = dispatch_queue_create("que", nil)
timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue)
dispatch_source_set_timer(timer, DISPATCH_TIME_NOW, 60 * NSEC_PER_SEC, 1 * NSEC_PER_SEC)
dispatch_source_set_event_handler(timer) {
var Time:Int!
var Posturevalue:Int!
var CoreID:String!
self.getData("Posturevalue", completionHandler: { (result) -> Void in
if (result == true) {
Posturevalue = self.GSValHolder
self.getData("Time", completionHandler: { (result) -> Void in
if (result == true) {
Time = self.GSValHolder
CoreID = self.GSCoreID
self.saveCoreData(Time, PostureVal: Posturevalue, CoreID: CoreID)
}
})
}
})
}
dispatch_resume(timer)
}
// Temporary constants to compose the URL. Has to be replaced with the values passed on from the CoreInfoView.
let DeviceID:String = "51ff72065082554944270887"
let Accesstoken:String = "09f54420e11539de00c13284f9fec31d3fba410d"
let session = NSURLSession.sharedSession()
//Sends a request to the URL to receive JSON data.
func getData(Variblename:String, completionHandler: (result:Bool!) -> Void)
{
let dataurl:String = "https://api.spark.io/v1/devices/"+DeviceID+"/"+Variblename+"/?access_token="+Accesstoken
if let url = NSURL(string: dataurl) {
let request = NSURLRequest(URL: url)
initialiseTaskForGettingData(request, element: "results", completionHandler: { (result) -> Void in
if (result == true) {
completionHandler(result: true)
}
else {
completionHandler(result: false)
}
})
}
}
//Handles the JSON data. Get the DeviceID and Variblevalue (Posture Value and Time value)
func initialiseTaskForGettingData(request: NSURLRequest, element:String, completionHandler: (result:Bool!) -> Void)
{
let task = session.dataTaskWithRequest(request) {data, response, downloadError in
if let error = downloadError
{
completionHandler(result: false)
}
else
{
var parsingError: NSError?
let parsedResult: AnyObject! = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.AllowFragments, error: &parsingError)
if let coreData = parsedResult as? NSDictionary {
if let VariableVal = (coreData as NSDictionary)["result"] as? Int {
if let coreInfo = coreData["coreInfo"] as? NSDictionary {
if let deviceID = (coreInfo as NSDictionary)["deviceID"] as? String {
println(deviceID)
println(VariableVal)
self.GSValHolder = VariableVal
completionHandler(result: true)
}
}
}
}
}
}
task.resume()
}
However, I figured out that the dataTaskWithRequest can be written with a completionHandler, but I could not make it work. I was wondering if that might make the code a bit more simple?