Create dynamic collectionview in one viewcontroller

Question

"I am new one for iOS development now I am working on collection view. Whenever view appears I will load data with the given array, then if user did select the cell again I want to load different data again, if there is no child in the array I want to load the previous data , these all should happen in one controller. The child data can be n number of data. i have a json like this"

func numberOfSections(in collectionView: UICollectionView) -> Int { return 1 }

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return item.count
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellIdentifier, for: indexPath) as! ProofAddressCell
    cell.nameLabel.text = item[indexPath.row]["address_title"] as? String
    return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

 if let childItem = item[indexPath.row]["child"] as? [[String: AnyObject]]  {
        if childItem.count > 1 {
        item = childItem
            let addItems: [[String: AnyObject]]!
           // addItems.append(item)
        collectionView.reloadData()
        }
        else {
             print("There is no option to show")
            let alert = UIAlertController(title: "Welcome", message: "No child available", preferredStyle: .alert)
            alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
            self.present(alert, animated: true, completion:{ () in

                self.moveBack()

            })
        }
    }
    else {
    print("There is no option to show")
    let alert = UIAlertController(title: "Welcome", message: "No child available", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
    self.present(alert, animated: true, completion:{ () in

        self.moveBack()

    })
    }
}

func moveBack() {
    print("have to move back")
    //item = childArray
}

When view appears i loaded the data title and subtitle as "Home" and "Firm" When home tapped i want to load "Home child 1" and "Home child 2" if user again clicks the "Home child 1" cell i want to load next child if child has value.

Please guide me how to implement this ?

Answer 1

First you want to use Decoder

struct Root: Codable {
    let captureMethod, addressTitle, addressSubtitle: String
    let addressRequired: Int
    let poafilename: String
    let child: [Root]
}

let decoder =  JSONDecoder() 
decoder.keyDecodingStrategy = .convertFromSnakeCase
let res = decoder.decode(Root.self,from:data)
item.append(res)

Second you need to keep a stack of previous path

var myStack = [[Root]]()
var item = [Root]()


if item[indexPath.row].child.count > 1  {
  myStack.append(item)
  item = item[indexPath.row].child
}
else {
  print("No more childs")
}

When you want to move back

if let las = myStack.last  {
  myStack = Array(myStack.dropLast())
  item = las
}
else {
  print("No more prevs")
}