I'm using the NSFetchedResultsController, to populate a UITableView, i'm trying to add a category filter, so if the user choose a category a need to reload the data on the UITableView, this is what i'm trying to do.
var categoriaAtual : Int?
var fetchedResultsController: NSFetchedResultsController {
if _fetchedResultsController != nil {
print("Already fetch")
return _fetchedResultsController!
} else {
print("New Fetch")
}
let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let managedContext = appDelegate.managedObjectContext
self.managedObjectContext = managedContext
let fetchRequest = NSFetchRequest()
// Edit the entity name as appropriate.
let entity = NSEntityDescription.entityForName("Frases", inManagedObjectContext: self.managedObjectContext!)
fetchRequest.entity = entity
// Set the batch size to a suitable number.
fetchRequest.fetchBatchSize = 20
// Edit the sort key as appropriate.
let sortDescriptor = NSSortDescriptor(key: "favorita", ascending: false)
fetchRequest.sortDescriptors = [sortDescriptor]
fetchRequest.fetchLimit = 20
if categoriaAtual != nil {
print("Categoria Atual \(categoriaAtual)")
fetchRequest.predicate = NSPredicate(format: "categoria = %d",categoriaAtual!)
fetchRequest.fetchLimit = 2
} else {
print("No predicate");
}
//
// Edit the section name key path and cache name if appropriate.
// nil for section name key path means "no sections".
let aFetchedResultsController = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext: self.managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil)
aFetchedResultsController.delegate = self
_fetchedResultsController = aFetchedResultsController
do {
try _fetchedResultsController!.performFetch()
} catch {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
//print("Unresolved error \(error), \(error.userInfo)")
abort()
}
return _fetchedResultsController!
}
var _fetchedResultsController: NSFetchedResultsController? = nil
func setarCategoria(cat: Int) {
categoriaAtual = cat
_fetchedResultsController = nil
self.tableView.reloadData()
}
Now i have a slide out menu called MenuTableView.swift,i make the call like this: ( I Think the problem is here )
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let homeVC = storyboard.instantiateViewControllerWithIdentifier("HomeViewController") as! HomeTableViewController
homeVC.setarCategoria(indexPath.row)
self.slideMenuController()?.closeLeft()
}
I do get the print saying that this is a new fetch, but the TableView does not change at all.
instantiateViewControllerWithIdentifer creates a new instance of the viewController (and therefore a new instance of the fetchedResultsController), which is how you get the "New Fetch" log but your original table view doesn't change. You probably just need to give MenuTableView a delegate that your HomeViewController can implement.
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