I am using the Flickr API to get all albums within a collection and then using the album IDs from to get the primary photo for each of the albums. It works but the photos are not returned to me in order so the primary photo for each album does not match up to the album titles in my collection view.
func getPhotoCollection() {
let collectionURLString = "https://api.flickr.com/services/rest/?method=flickr.collections.getTree&api_key={API_KEY}&collection_id=72157676119666248&user_id={USER_ID}&format=json&nojsoncallback=1"
self.session = URLSession(configuration: .default, delegate: self, delegateQueue: nil)
let task = self.session?.dataTask(with: URL(string: collectionURLString)!, completionHandler: { (data, response, error) in
let json = self.getJSONFrom(urlString: collectionURLString)
let collections = json["collections"]
let collection = collections["collection"].arrayObject as! [[String:AnyObject]]
for collectionObject in collection {
let sets = collectionObject["set"] as! [[String: AnyObject]]
for set in sets {
let albumId = set["id"] as! String
let albumTitle = set["title"] as! String
self.albumIds.append(albumId)
self.albumTitles.append(albumTitle)
}
}
self.getAlbumPrimary()
})
task?.resume()
}
func getAlbumPrimary() {
for albumId in self.albumIds {
let apiURLString = "https://api.flickr.com/services/rest/?method=flickr.photosets.getPhotos&api_key={API_KEY}&photoset_id=\(albumId)&per_page=1&user_id={USER_ID}&format=json&nojsoncallback=1"
self.session = URLSession(configuration: .default, delegate: self, delegateQueue: nil)
let task = self.session?.dataTask(with: URL(string: apiURLString)!, completionHandler: { (data, response, error) in
let json = self.getJSONFrom(urlString: apiURLString)
let photos = json["photoset"]
let photo = photos["photo"].arrayObject as! [[String:AnyObject]]
let primaryPic = photo[0]
let farm = primaryPic["farm"] as! Int
let server = primaryPic["server"] as! String
let picId = primaryPic["id"] as! String
let secret = primaryPic["secret"] as! String
let urlString = String(format: "https://farm%d.static.flickr.com/%#/%#_%#_b.jpg", farm, server, picId, secret)
self.albumPrimaryURLs.append(urlString)
DispatchQueue.main.async {
self.collectionView.reloadData()
self.loaded = true
}
})
task?.resume()
}
}
This is the way multiple asynchronous tasks work ( out of order ) ,you need to create a model instead of seperate arrays then load from the data to fill the last property
class Item {
let id,title:String
var url:String?
init(id:String,title:String){
self.id = id
self.title = title
}
func loadUrl(completion:#escaping () -> () ) {
// here load and set the url
}
}
var items = [Item]() // declare main array
let albumId = set["id"] as! String
let albumTitle = set["title"] as! String
let item = Item(id:albumId,title:albumTitle)
self.items.append(item)
Then to load the collection finally
let g = DispatchGroup()
items.forEach {
g.enter()
$0.loadUrl {
g.leave()
}
}
g.notify(queue:.main) {
self.collectionView.reloadData()
self.loaded = true
}
Related
I want to load all data from firebase, then show the data to the table view. But now, I can't show all the data to the table view. It is because call the finishLoading(realm) method is faster than the for loop get all the data. How can I do some show all data when for loop is finish in swift. I have to use the Closure, however the second of the loop is later than this "self.finishLoading(realm: realm)"
I have to try to add the DispatchGroup(), however, the leave() when having an error of EXC_BAD_INSTRUCTION. Can I put the leave() in the closure? How can I fix it?
func loopAllProduct(userId: String, finishLoadWhenErr:Bool, storedClosure: #escaping (DocumentSnapshot) -> Void){
let storage = Storage.storage()
let db = Firestore.firestore()
let userDocRef = db.collection("Users").document(userId).collection("Product")
userDocRef.getDocuments{(document, error) in
if let err = error {
print("Error getting documents: \(err)")
} else {
for document in document!.documents {
storedClosure(document)
}
}
}
}
func downloadData() {
let startTime = Date()
while updating {
let diffTime = Date(timeIntervalSinceReferenceDate: startTime.timeIntervalSinceReferenceDate)
if (diffTime.timeIntervalSinceNow < -5){
self.stopAnimating()
self.refreshControl?.endRefreshing()
print("Update Timeout")
return
}
}
updating = true
let storage = Storage.storage()
let db = Firestore.firestore()
let productLoading = NSMutableArray()
let realm = try! Realm()
print("all posts")
let group = DispatchGroup()
let addPosts: (DocumentSnapshot)->Void = {(document) in
try! realm.write {
if let resuls = self.realmResults {
realm.delete(resuls);
}
}
let product = Product()
product.id = document.documentID
product.userID = document.data()?["UserID"] as? String
product.userName = document.data()?["UserName"] as? String
product.descrition = document.data()?["Descrition"] as? String
product.postTime = document.data()?["PostTime"] as? Date
product.price = document.data()?["Price"] as? Double ?? 0.0
product.stat = (document.data()?["stat"] as? Int)!
product.productName = document.data()?["ProductName"] as? String
let productId = document.documentID
productLoading.add(productId)
try! realm.write {
realm.add(product)
}
group.leave()
}
let userDocRef = db.collection("Users")
userDocRef.getDocuments{(document, error) in
for document in document!.documents {
group.enter()
self.loopAllProduct(userId:document.documentID , finishLoadWhenErr: true, storedClosure: addPosts)
}
}
group.notify(queue: DispatchQueue.main) {
self.finishLoading(realm: realm)
}
}
I have looked at a lot of questions and I do not believe this is a result of reusing a cell as the new cells image is correct, but and existing cells image is incorrect and used to be correct. I'll post the images first so the issue is easier to understand.
I have a collectionView of image cells (similar to Instagrams user page). I'm fetching all of the data from Firebase. I get the first 12 posts on the initial loading of the screen. However, if you scroll down quickly an EXISTING cells image changes to a newly fetched image. I'm not sure why this is happening... Maybe it's a caching issue? The issue only occurs the first time you load the screen. I've tried setting the images to nil like this:
override func prepareForReuse() {
super.prepareForReuse()
self.imageView.image = UIImage()
}
This didn't help the issue though.
Here is my cellForItemAt:
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "imageCell", for: indexPath) as! ImageCell
cell.indexPath = indexPath
cell.imageView.downloadImage(from: currentTablePosts[indexPath.row].pathToImage)
cell.layer.borderWidth = 1
cell.layer.borderColor = UIColor.black.cgColor
return cell
}
Image downloading and caching:
let imageCache = NSCache<NSString, UIImage>()
extension UIImageView {
func downloadImage(from imgURL: String!) {
let url = URLRequest(url: URL(string: imgURL)!)
// set initial image to nil so it doesn't use the image from a reused cell
image = nil
// check if the image is already in the cache
if let imageToCache = imageCache.object(forKey: imgURL! as NSString) {
self.image = imageToCache
return
}
// download the image asynchronously
let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
if error != nil {
// user an alert to display the error
if let topController = UIApplication.topViewController() {
Helper.showAlertMessage(vc: topController, title: "Error Downloading Image", message: error as! String)
}
return
}
DispatchQueue.main.async {
// create UIImage
let imageToCache = UIImage(data: data!)
// add image to cache
imageCache.setObject(imageToCache!, forKey: imgURL! as NSString)
self.image = imageToCache
}
}
task.resume()
}
}
Firebase Queries:
static func getInitialTablesPosts(tableNumber: String) {
tableReference.child(tableNumber).queryLimited(toLast: 12).observeSingleEvent(of: .value, with: { snap in
for child in snap.children {
let child = child as? DataSnapshot
if let post = child?.value as? [String: AnyObject] {
let posst = Post()
if let author = post["author"] as? String, let likes = post["likes"] as? Int, let pathToImage = post["pathToImage"] as? String, let postID = post["postID"] as? String, let postDescription = post["postDescription"] as? String, let timestamp = post["timestamp"] as? Double, let category = post["category"] as? String, let table = post["group"] as? String, let userID = post["userID"] as? String, let numberOfComments = post["numberOfComments"] as? Int, let region = post["region"] as? String {
posst.author = author
posst.likes = likes
posst.pathToImage = pathToImage
posst.postID = postID
posst.userID = userID
posst.fancyPostDescription = Helper.createAttributedString(author: author, postText: postDescription)
posst.postDescription = author + ": " + postDescription
posst.timestamp = timestamp
posst.table = table
posst.region = region
posst.category = category
posst.numberOfComments = numberOfComments
posst.userWhoPostedLabel = Helper.createAttributedPostLabel(username: author, table: table, region: region, category: category)
if let people = post["peopleWhoLike"] as? [String: AnyObject] {
for(_, person) in people {
posst.peopleWhoLike.append(person as! String)
}
}
currentTablePosts.insert(posst, at: 0)
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "reloadTableCollectionView"), object: nil)
} // end of if let
}
}
})
tableReference.removeAllObservers()
}
static func getMoreTablePosts(tableNumber: String, lastVisibleKey: String) {
print("FIRED...")
let currentNumberOfPosts = currentTablePosts.count
print("Number of posts before fetiching ", currentNumberOfPosts)
print("Oldest post key ", oldestTableKeys[tableNumber] ?? "not set yet", "***********")
tableReference.child(tableNumber).queryOrderedByKey().queryEnding(atValue: lastVisibleKey).queryLimited(toLast: 12).observeSingleEvent(of: .value, with: { snap in
for child in snap.children {
let child = child as? DataSnapshot
if let post = child?.value as? [String: AnyObject] {
if let id = post["postID"] as? String {
if id == lastVisibleKey {
return
}
}
let posst = Post()
if let author = post["author"] as? String, let likes = post["likes"] as? Int, let pathToImage = post["pathToImage"] as? String, let postID = post["postID"] as? String, let postDescription = post["postDescription"] as? String, let timestamp = post["timestamp"] as? Double, let category = post["category"] as? String, let table = post["group"] as? String, let userID = post["userID"] as? String, let numberOfComments = post["numberOfComments"] as? Int, let region = post["region"] as? String {
posst.author = author
posst.likes = likes
posst.pathToImage = pathToImage
posst.postID = postID
posst.userID = userID
posst.fancyPostDescription = Helper.createAttributedString(author: author, postText: postDescription)
posst.postDescription = author + ": " + postDescription
posst.timestamp = timestamp
posst.table = table
posst.region = region
posst.category = category
posst.numberOfComments = numberOfComments
posst.userWhoPostedLabel = Helper.createAttributedPostLabel(username: author, table: table, region: region, category: category)
if let people = post["peopleWhoLike"] as? [String: AnyObject] {
for(_, person) in people {
posst.peopleWhoLike.append(person as! String)
}
}
currentTablePosts.insert(posst, at: currentNumberOfPosts)
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "reloadTableCollectionView"), object: nil)
if let oldestTableKey = oldestTableKeys[tableNumber] {
if postID == oldestTableKey {
print("returning")
print("number of posts on return \(currentTablePosts.count)")
return
}
}
} // end if let
}
}
})
tableReference.removeAllObservers()
}
* UPDATE *
The image caching used here still had some issues in my experience. I have since moved on to using Kingfisher which is extremely easy to setup and use.
* OLD SOLUTION *
Found a solution based on the answer suggested in the comments.
I modified the extension I am using to cache my images. Although in the future I think I will subclass UIImageView. Here is the modified version of my code.
import UIKit
let userImageCache = NSCache<NSString, UIImage>()
let imageCache = NSCache<AnyObject, AnyObject>()
var imageURLString: String?
extension UIImageView {
public func imageFromServerURL(urlString: String, collectionView: UICollectionView, indexpath : IndexPath) {
imageURLString = urlString
if let url = URL(string: urlString) {
image = nil
if let imageFromCache = imageCache.object(forKey: urlString as AnyObject) as? UIImage {
self.image = imageFromCache
return
}
URLSession.shared.dataTask(with: url, completionHandler: { (data, response, error) in
if error != nil{
if let topController = UIApplication.topViewController() {
Helper.showAlertMessage(vc: topController, title: "Error Downloading Image", message: error as! String)
}
return
}
DispatchQueue.main.async(execute: {
if let imgaeToCache = UIImage(data: data!){
if imageURLString == urlString {
self.image = imgaeToCache
}
imageCache.setObject(imgaeToCache, forKey: urlString as AnyObject)// calls when scrolling
collectionView.reloadItems(at: [indexpath])
}
})
}) .resume()
}
}
func downloadImage(from imgURL: String!) {
let url = URLRequest(url: URL(string: imgURL)!)
// set initial image to nil so it doesn't use the image from a reused cell
image = nil
// check if the image is already in the cache
if let imageToCache = imageCache.object(forKey: imgURL! as AnyObject) as? UIImage {
self.image = imageToCache
return
}
// download the image asynchronously
let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
if error != nil {
// user an alert to display the error
if let topController = UIApplication.topViewController() {
Helper.showAlertMessage(vc: topController, title: "Error Downloading Image", message: error as! String)
}
return
}
DispatchQueue.main.async {
let imageToCache = UIImage(data: data!)
imageCache.setObject(imageToCache!, forKey: imgURL! as AnyObject)
self.image = imageToCache
}
}
task.resume()
}
func downloadUserImage(from imgURL: String!) {
let url = URLRequest(url: URL(string: imgURL)!)
// set initial image to nil so it doesn't use the image from a reused cell
image = nil
// check if the image is already in the cache
if let imageToCache = userImageCache.object(forKey: imgURL! as NSString) {
self.image = imageToCache
return
}
// download the image asynchronously
let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
if error != nil {
// user an alert to display the error
if let topController = UIApplication.topViewController() {
Helper.showAlertMessage(vc: topController, title: "Error Downloading Image", message: error as! String)
}
return
}
DispatchQueue.main.async {
// create UIImage
let imageToCache = UIImage(data: data!)
// add image to cache
userImageCache.setObject(imageToCache!, forKey: imgURL! as NSString)
self.image = imageToCache
}
}
task.resume()
}
}
I created the first method to cache the images for the collectionView and the other methods are still used for tableViews. The cache was also changed from let imageCache = NSCache<NSString, UIImage>() to let imageCache = NSCache<AnyObject, AnyObject>()
With this code i can show the "result"
var movies: [NSDictionary]?
var dates: NSDictionary?
func fetchNowPlayingMovies(){
let apiKey = "8e3967947a95555f9c430e68d070a0e7"
let url = URL(string: "https://api.themoviedb.org/3/movie/now_playing?api_key=\(apiKey)"+"&language=en-US&page=1")
let request = URLRequest(url: url! as URL, cachePolicy: URLRequest.CachePolicy.reloadIgnoringCacheData, timeoutInterval: 10)
let session = URLSession(configuration: URLSessionConfiguration.default, delegate: nil, delegateQueue: OperationQueue.main)
let task: URLSessionDataTask = session.dataTask(with:request, completionHandler: {(dataOrNil, reponse, error) in
if let data = dataOrNil{
if let responseDictionary = try! JSONSerialization.jsonObject(with: data, options: []) as? NSDictionary {
//print("reponse: \(responseDictionary)")
self.movies = responseDictionary["results"] as? [NSDictionary]
self.dates = responseDictionary["dates"] as? NSDictionary
self.tableView.reloadData()
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
task.resume()
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "MovieCell", for: indexPath) as! MovieTableViewCell
//MARK: - JSON Properties
let movie = movies![indexPath.row]
let date = dates![indexPath.row]
let title = movie["title"] as! String
let vote_average = movie["vote_average"] as! Double
let overview = movie["overview"] as! String
let baseUrl = "http://image.tmdb.org/t/p/w500"
let posterPath = movie["poster_path"] as! String
let imageUrl = URL(string: baseUrl + posterPath)
// Configure the cell...
cell.lblTitle.text = title
cell.lblOverview.text = overview
cell.lblVoteAVG.text = String(vote_average)
cell.imgPosterPath.sd_setImage(with: imageUrl)
return cell
}
Request: https://api.themoviedb.org/3/movie/now_playing?api_key=8e3967947a95555f9c430e68d070a0e7&language=en-US&page=1
How i can get the "page" and the "maximum" in "dates"?
Thank you!
var movies: [NSDictionary]?
var dates: NSDictionary?
var page: Int? // var for page
var maximum: String? // var for maximum in dates
func fetchNowPlayingMovies(){
let apiKey = "8e3967947a95555f9c430e68d070a0e7"
let url = URL(string: "https://api.themoviedb.org/3/movie/now_playing?api_key=\(apiKey)"+"&language=en-US&page=1")
let request = URLRequest(url: url! as URL, cachePolicy: URLRequest.CachePolicy.reloadIgnoringCacheData, timeoutInterval: 10)
let session = URLSession(configuration: URLSessionConfiguration.default, delegate: nil, delegateQueue: OperationQueue.main)
let task: URLSessionDataTask = session.dataTask(with:request, completionHandler: {(dataOrNil, reponse, error) in
if let data = dataOrNil{
if let responseDictionary = try! JSONSerialization.jsonObject(with: data, options: []) as? NSDictionary {
//print("reponse: \(responseDictionary)")
self.movies = responseDictionary["results"] as? [NSDictionary]
self.dates = responseDictionary["dates"] as? NSDictionary
// This is how you get to page
print("page: \(responseDictionary["page"]!)")
self.page = responseDictionary["page"] as? Int
print("page: \(self.page!)")
// This is how you get to maximum in dates
self.maximum = self.dates?["maximum"] as? String
print("maximum: \(self.maximum!)")
self.tableView.reloadData()
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
task.resume()
}
I hope it helped
My problem arises when I want to populate data from my mysql database into a class object. I am trying to return an array of objects and it returns nil and then it fills itself somehow. How can I make it fill before returning the blank array?
Here is my code and a screenshot of code output
import Foundation
class Research
{
var mainResearchImageURL:String = ""
var userProfileImageURL:String = ""
var caption:String = ""
var shortDescription:String = ""
init(mainResearchImageURL :String, userProfileImageURL:String, caption:String, shortDescription:String)
{
self.mainResearchImageURL = mainResearchImageURL
self.userProfileImageURL = userProfileImageURL
self.caption = caption
self.shortDescription = shortDescription
}
class func downloadAllResearches()->[Research]
{
var researches = [Research]()
let urlString = "http://localhost/test/index.php"
let request = NSMutableURLRequest(URL: NSURL(string: urlString)!)
request.HTTPMethod = "POST"
let postString = "action=listresearches"
request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request, completionHandler: {data, response, error in
if (error == nil) {
do {
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as? NSArray
//let dictionary = json!.firstObject as? NSDictionary
var counter:Int = 0;
for line in json!{
let researchData = line as! NSDictionary
let researchLineFromData = Research(mainResearchImageURL: researchData["research_mainImageURL"] as! String, userProfileImageURL: researchData["research_creatorProfileImageURL"] as! String, caption: researchData["research_caption"] as! String, shortDescription: researchData["research_shortDescription"] as! String)
researches.append(researchLineFromData) //researches bir dizi ve elemanları Research türünde bir sınıftan oluşuyor.
counter += 1
print ("counter value \(counter)")
print("array count in loop is = \(researches.count)")
}
}catch let error as NSError{
print(error)
}
} else {
print(error)
}})
task.resume()
print("array count in return is = \(researches.count)")
return researches
}
}
And this is the output:
add this on you completionHandler ( it works if you update a view)
dispatch_async(dispatch_get_main_queue(), {
if (error == nil) { ...... }
})
Advice 1:
return the task and use a completion param in your method,
you can cancel the task if it's too slow.
Advice 2 :
Use alamofire and swiftyJson framework
What happen here is that you are returning the value before finish (remember that the call is Asynchronous), you can make something like this:
class func downloadAllResearches(success:([Research])->Void,failure:(String)->Void)
{
var researches = [Research]()
let urlString = "http://localhost/test/index.php"
let request = NSMutableURLRequest(URL: NSURL(string: urlString)!)
request.HTTPMethod = "POST"
let postString = "action=listresearches"
request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request, completionHandler: {data, response, error in
if (error == nil) {
do {
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as? NSArray
//let dictionary = json!.firstObject as? NSDictionary
var counter:Int = 0;
for line in json!{
let researchData = line as! NSDictionary
let researchLineFromData = Research(mainResearchImageURL: researchData["research_mainImageURL"] as! String, userProfileImageURL: researchData["research_creatorProfileImageURL"] as! String, caption: researchData["research_caption"] as! String, shortDescription: researchData["research_shortDescription"] as! String)
researches.append(researchLineFromData) //researches bir dizi ve elemanları Research türünde bir sınıftan oluşuyor.
counter += 1
print ("counter value \(counter)")
print("array count in loop is = \(researches.count)")
}
success(researches)
}catch let error as NSError{
print(error)
failure("Can be extract from NSERROR")
}
} else {
print(error)
failure("Error - Can be extract for NSERROR")
}})
task.resume()
}
And for call this Fuction use something like this:
Research.downloadAllResearches({ (objects:[Research]) -> Void in
dispatch_async(dispatch_get_main_queue(), { () -> Void in
//Do whatever you like with the content
})
}) { (failureLiteral:String) -> Void in
}
So I'm fetching data from a url which is in a json format. I'm trying to display the data in my tableview but, even though it feels simple, I can't figure out how to do it.
class CompanyModel {
func getJSON() {
let companyArray: NSMutableArray = NSMutableArray()
let requestURL: NSURL = NSURL(string: "http://localhost/Companies/JSON.php")!
let urlRequest: NSMutableURLRequest = NSMutableURLRequest(URL: requestURL)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithRequest(urlRequest) {
(data, response, error) -> Void in
let httpResponse = response as! NSHTTPURLResponse
let statusCode = httpResponse.statusCode
if (statusCode == 200) {
print("Everyone is fine, file downloaded successfully.")
do{
let json = try NSJSONSerialization.JSONObjectWithData(data!, options:.AllowFragments)
if let companies = json["companies"] as? [[String: AnyObject]] {
for company in companies {
if let name = company["name"] as? String,
let phoneNumber = company["phone_number"] as? String,
let website = company["website"] as? String,
let email = company["email"] as? String,
let address = company["address"] as? String
{
let company = CompanyModel()
company.name = name
company.phoneNumber = phoneNumber
company.website = website
company.email = email
company.address = address
}
companyArray.addObject(company)
print(companyArray)
}
}
} catch {
print("Error with Json: \(error)")
}
}
print(companyArray) <- array is populated
}
print(companyArray) <- array is empty
task.resume()
}
}
I know i've done it before....I'm guessing in viewDidLoad() I'd call CompanyModel().getJSON() which would fetch the data, then store it in an empty array but my mind feels blank on how to do it.
I can't declare a variable of NSarray and store the data of it the variable directly for me to then populate the tableview. Nevertheless, I hope this explains what I'm trying to acheive.
Well first change the function to return your company array :
func getJSON() -> NSMutableArray {
}
By the end of the for loop return the company array
for company in companies {
}
After your array is populated, return the array inside this block:
dispatch_async(dispatch_get_main_queue(), {
return companyArray
})
And after task.resume() return the array:
return companyArray
From anywhere you wanna call this class and get the array :
Get a reference of the class
Let companyModal = CompanyModel()
And in anywhere you have your table view and the class let's say in viewDidLoad, you should first have NSMutableArray.
var arraySource = NSMutableArray()
And in viewDidLoad :
arraySource = companyModal.getJSON()
And to show the data in tableView do :
Mytableview.reloadData()
You can't use return within the closure of an asynchronous network request, you have to use a callback instead.
You need a NSMutableArray from the request, so first, let's make a callback for this:
completion: (array: NSMutableArray)->()
We add this callback to the method signature:
func getJSON(completion: (array: NSMutableArray)->())
And then at the location where the array will be available, we place this completion handler:
class CompanyModel {
func getJSON(completion: (array: NSMutableArray)->()) {
let companyArray: NSMutableArray = NSMutableArray()
let requestURL: NSURL = NSURL(string: "http://localhost/Companies/JSON.php")!
let urlRequest: NSMutableURLRequest = NSMutableURLRequest(URL: requestURL)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithRequest(urlRequest) {
(data, response, error) -> Void in
let httpResponse = response as! NSHTTPURLResponse
let statusCode = httpResponse.statusCode
if (statusCode == 200) {
do{
let json = try NSJSONSerialization.JSONObjectWithData(data!, options:.AllowFragments)
if let companies = json["companies"] as? [[String: AnyObject]] {
for company in companies {
if let name = company["name"] as? String,
let phoneNumber = company["phone_number"] as? String,
let website = company["website"] as? String,
let email = company["email"] as? String,
let address = company["address"] as? String {
let company = CompanyModel()
company.name = name
company.phoneNumber = phoneNumber
company.website = website
company.email = email
company.address = address
companyArray.addObject(company)
}
}
// CALLBACK HERE
completion(array: companyArray)
}
} catch {
print("Error with Json: \(error)")
}
}
}
task.resume()
}
}
Now to get the array from the network we use a trailing closure like this:
getJSON { (array) in
print(array)
}