CODEWITHSUNDEEP
iosswiftuitableviewcore-dataswift3
Danil Mihnevich
Danil Mihnevich

Reputation: 45

CoreData seems to save wrong variable

I am trying to debug the below code.

1) CellClass has IBAction to change Bool value, the value declared as value: Bool

@IBAction func dashBrnPressed(_ sender: AnyObject) {
  value == true ? (value = false) : (value = true)
  NotificationCenter.default.post(name: .reload, object: nil)
                                      // reloads the TableView
 }

2) I use UITableView controller with dequeueReusableCell and fetching CoreData. There is these lines only responcible for cell. "switchAction" is a value from CoreData

 if cell.value == true{
     switchAction.isOn = true

  }else{
     switchAction.isOn = false

  }

  DataBaseController.saveContext()
  cell.value = switchAction.isOn

  return cell

3) it seems to be working unless I restart the app. No crashes but it returns FALSE for value by default. I need store the value back to CoreData depending on what statement the button is.

The code is simplified of course.

Upvotes: 2

Views: 109

Answers (2)

Danil Mihnevich
Danil Mihnevich

Reputation: 45

The reason is still unknowm but this code works

1) cell.value now is optional and equals nil while restarting the app

2) This code in cellForRow now firstly assigns optional value and only if the value exist stores the new value 3) function willDisplay doesnt return UITableViewCell and not required

 switch cell.value {  
    case nil:

        if switchAction.dashboard == true{
            cell.dashBtn.tintColor = .white
            cell.value = true

        } else {

            cell.dashBtn.tintColor = myColors.opaceGrayColor
            cell.value = false
        }

    case true?:

    switchAction.dashboard = true
    cell.dashBtn.tintColor = .white
    DataBaseController.saveContext()


    case false?:

    switchAction.dashboard = false
    cell.dashBtn.tintColor = myColors.opaceGrayColor
    DataBaseController.saveContext()
}

I am happy and thank you for help! :)

Upvotes: 0

Robert
Robert

Reputation: 6810

I think I see the problem. In the block of code under part 2, here's what you're doing:

  1. Set switchAction.isOn to the value of cell.value
  2. Save switchAction.isOn to CoreData
  3. Set cell.value to the value of switchAction.isOn

When you restart your app, cell.value defaults to false, and then you overwrite that false onto switchAction.isOn and save it back to CoreData. So even though switchAction.isOn might be loading with the correct value, you're overwriting it before you ever see it.

What you need is an assignment that goes the other way:

cell.value = switchAction.isOn

Since cell is a reusable table view cell, you can put that line in your tableView(UITableView, willDisplay: UITableViewCell, forRowAt: IndexPath) delegate function, which is called right before the cell is displayed.

Upvotes: 1

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