Swift 3.0 multiple selection with select all cell

I have added data in table view and I have manually added "select all" option to the list at first position, now when the user selects the first option which is 'select all' then the person manually option "Select all" is not selected. Select all, click then work all person or deselect working but signal selection all the person not working "Select all" I have tried the code below but it's not working so can any one help me to solve this?

var unchecked:Bool = true
        func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
            // create a new cell if needed or reuse an old one
            let cell = ObjTableview.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! SelectUserCell
            // set the text from the data model
             cell.selectionStyle = UITableViewCellSelectionStyle.none
            cell.lblStudentName.text = getStudentName[indexPath.row]

            if UnAll == "unselect" {
                if indexPath.row == 0 {
                    cell.btnCheckbox.setImage(UIImage(named: "unSelectedItem"), for: .normal)

                }
                if indexPath.row == Int(selectedNumber) {
                    cell.btnCheckbox.setImage(UIImage(named: "unSelectedItem"), for: .normal)

                }
                if indexPath.row == Int(unSelectNumber) {
                    //var j = "\(i)"

                    cell.btnCheckbox.setImage(UIImage(named: "selectedItem"), for: .normal)

                }

            }else
            {
            if(unchecked){

                cell.btnCheckbox.setImage(UIImage(named: "unSelectedItem"), for: .normal)

            }
            else{

                cell.btnCheckbox.setImage(UIImage(named: "selectedItem"), for: .normal)

              }
            }

            return cell
        }
        var UnAll = ""
        var selectedNumber = ""
        var unSelectNumber = ""
        var checkselect:Bool = true

        func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

            UnAll.removeAll()
            selectedNumber.removeAll()
            unSelectNumber.removeAll()
            if(indexPath.row == 0){

                btnCheckBoxClick(sender: UIButton())

            }else
            {
            UnAll = "unselect"
                btnCheckBoxClick(sender: UIButton())
                if checkselect {
                    selectedNumber = "\(indexPath.row)"
                    checkselect = false
                }else
                {
                  unSelectNumber = "\(indexPath.row)"
                    checkselect = true
                }

                print("the selected index is : \(indexPath.row)")
            }

        }

        @IBAction func btnCheckBoxClick(_ sender: Any) {   

            if(unchecked){

                unchecked = false
            }
            else{              
                unchecked = true
            }
            ObjTableview.reloadData()
         }

Solution

Create a struct for model data with a Bool property. You can modify this property by cell selection.

class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

  var allCharacters:[Character] = []

  override func viewDidLoad() {
    super.viewDidLoad()
        allCharacters = [Character(name: "All"),Character(name: "Luke Skywalker"),Character(name: "Leia Organa"),Character(name: "Advik Shah"),Character(name: "Aarav Modi")]

  }
  func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return allCharacters.count
  }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    var cell = tableView.dequeueReusableCell(withIdentifier: "Cell")
    if cell == nil{
      cell = UITableViewCell(style: .subtitle, reuseIdentifier: "Cell")
    }
      cell?.textLabel?.text = allCharacters[indexPath.row].name
      if allCharacters[indexPath.row].isSelected
      {
        cell?.accessoryType = .checkmark
      }
      else
      {
        cell?.accessoryType = .none
      }
      cell?.selectionStyle = .none
    return cell!
  }
  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    if indexPath.row == 0
    {
      allCharacters[indexPath.row].isSelected = !allCharacters[indexPath.row].isSelected
      for index in allCharacters.indices
      {
        allCharacters[index].isSelected = allCharacters[indexPath.row].isSelected
      }
    }
    else
    {
      allCharacters[indexPath.row].isSelected = !allCharacters[indexPath.row].isSelected
      if allCharacters.dropFirst().filter({ $0.isSelected }).count == allCharacters.dropFirst().count
      {
        allCharacters[0].isSelected = true
      }
      else
      {
        allCharacters[0].isSelected = false
      }
    }
    tableView.reloadData()
  }




}

struct Character
{
  var name:String
  //  var otherDetails
  var isSelected:Bool! = false
  init(name:String) {
    self.name = name
  }
}

Creating Array of Struct objects from array of dictionary

let SubjectArray = json["students"] as! [[String:Any]]
allCharacters = SubjectArray.map({ Character(name: $0["studentName"] as! String) })
allCharacters.insert(Character(name:"All"), at: 0)