How can I pass core data information from a table view to a view controller?

Question

My app has a UITableView that displays brief data about an item, and I'm trying to send the user to another viewController when they press on a cell. That viewController is named detailViewController and I want it to display more details about the selected cell. I'm using core data, and my problem lies here. I do not know how I would pass one specific object stored in cordite to another view controller. Here is my code:

var tasks: Array<AnyObject> = [] //Creating an array that will store fetched data

override func viewWillAppear(animated: Bool) {

let appDel: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
let contexts: NSManagedObjectContext = appDel.managedObjectContext!
let fetchreq = NSFetchRequest(entityName: "toDo")

tasks = contexts.executeFetchRequest(fetchreq, error: nil)!
tableView.reloadData()

}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {


let CellID: NSString = "myCell"

var cell: CustomCell = tableView.dequeueReusableCellWithIdentifier(CellID) as CustomCell

if let indexpth = indexPath as NSIndexPath! {

    var data: NSManagedObject = tasks[indexpth.row] as NSManagedObject
    cell.theTextLabel?.text = data.valueForKeyPath("toDoName") as? String

    cell.theDetailTextLabel?.text = data.valueForKeyPath("toDoNumber") as? String

}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.

    if segue.identifier == "showDetail" {

        var detailVC: DetailViewController = segue.destinationViewController as DetailViewController

        var index: NSIndexPath = self.tableView.indexPathForSelectedRow()!
        var row: NSInteger = index.row

        var myData: NSManagedObject = tasks[row] as NSManagedObject

        var tName: AnyObject? = testData.valueForKeyPath("tName")
        detailVC.detailTasks = myData
        detailVC.detailName = tName

    }

}

I'm not sure how I would pass an object stored in core data to another view controller, I've tried many things but it doesn't seem to work. Thanks guys!

Answer 1

I solved my problem after trying a few things, the code below worked for me. In my DetailViewController I changed the from a label to a text field to display the information. I created a variable detailName of type string and dropped my data in there.Thanks for you help guys!

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {


    if segue.identifier == "showDetail" {

        var detailVC: DetailViewController = segue.destinationViewController as DetailViewController

        var selectedItem: NSManagedObject = tasks[self.tableView.indexPathForSelectedRow()!.row] as NSManagedObject

        detailVC.detailName = selectedItem.valueForKey("tName") as String

    }

Answer 2

Check to make sure that your detailVC has been allocated and initialized before you pass along any data. I'm guessing this is the issue.