Reloading UICollection view after data parse - ios

Question

I am trying to dynamically update a uicollectionview. I used this amazing tutorial on how to create a simple uicollection.
It works great when using a static array of items. My issue - I would like to have the uicollection populate with data I parsed into a new array from my db. I am not sure how to reload the uicollection after parsing my json data.
UPDATED CODE WITH ANSWER:
import UIKit
class Books: UIViewController, UICollectionViewDelegate {
#IBOutlet weak var bookscollection: UICollectionView!
var user_id: Int = 0;
//------------ init ---------------//
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
showtutorial()
getuserid()
}
//------------ show books ---------------//
var booknames = [String]()
var bookcolor = [String]()
var bookdescription = [String]()
var bookid = [Int]()
func posttoapi(){
//show loading
LoadingOverlay.shared.showOverlay(view: self.view)
//send
let url:URL = URL(string: "http://www.url.com")!
let session = URLSession.shared
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.cachePolicy = NSURLRequest.CachePolicy.reloadIgnoringCacheData
let paramString = "user_id=\(user_id)"
request.httpBody = paramString.data(using: String.Encoding.utf8)
let task = session.dataTask(with: request as URLRequest) {(data, response, error) in
//hide loading
LoadingOverlay.shared.hideOverlayView()
//no response
guard let data = data, let _:URLResponse = response, error == nil else {
print("response error")
return
}
//response, parse and send to build
let json = String(data: data, encoding: String.Encoding.utf8);
if let data = json?.data(using: String.Encoding.utf8){
let json = try! JSON(data: data)
for item in json["rows"].arrayValue {
//push data to arrays
self.booknames.append(item["name"].stringValue)
self.bookcolor.append(item["color"].stringValue)
self.bookdescription.append(item["description"].stringValue)
self.bookid.append(item["id"].int!)
//reload uicollection
DispatchQueue.main.sync(execute: {
self. bookscollection.reloadData()
})
}
}
}
task.resume()
}
//------------ collection -------------//
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
print("collection view code called")
return self.booknames.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = bookscollection.dequeueReusableCell(withReuseIdentifier: reuseIdentifier, for: indexPath as IndexPath) as! BooksCell
cell.myLabel.text = self.booknames[indexPath.item]
cell.backgroundColor = UIColor.cyan // make cell more visible in our example project
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("You selected cell #\(indexPath.item)!")
}
//------------ end ---------------//
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
Thank you for any help!

Answer 1

Same problem i faced..your url having many images means reload t
dispatch_async(dispatch_get_main_queue(), {
self.collectionView.reloadData()
})