I am working on a core data application and currently I have the methods setup correctly to save the primary object saves the name of the users deck but it doesn't save recall the secondary object even though the method used to save both is identical. The primary does save second though and I am wondering if it matters the order that objects are saved. I know it is a relational but I figured it wouldn't matter if the secondary was called to save prior to the primary. I am still new to core data so just a simple answer is enough. If I need to save the primary entity object first then I will build the app in such a way that such occurs, else I may have to relook at the code to figure out why it isn't recalling.
This is the code that is supposed to save prior to the name being saved in a relational manner:
#IBAction func buttonWarrior(sender: AnyObject) {
let entity = NSEntityDescription.entityForName("ClassSelection", inManagedObjectContext: classMOC!)
let newObject = ClassSelection(entity: entity!,insertIntoManagedObjectContext: classMOC)
newObject.classname = "Warrior"
var error: NSError?
classMOC?.save(&error)
if let err = error {
println(err)
} else {
self.performSegueWithIdentifier("popOver", sender: self)
}
}
This is the code used to store the primary object which is a different viewcontroller.swift file than the other one. This is presented as a popover box over the secondary object. This part works fine and recalls correctly :
#IBAction func enterButton(sender: AnyObject) {
let entityDescription = NSEntityDescription.entityForName("Deck",inManagedObjectContext: managedObjectContext!)
let storeDeck = Deck(entity: entityDescription!,insertIntoManagedObjectContext: managedObjectContext)
storeDeck.deckname = usersDeckName.text
var error: NSError?
managedObjectContext?.save(&error)
if let err = error {
status.text = err.localizedFailureReason
} else {
usersDeckName.text = ""
status.text = "Deck Saved"
self.performSegueWithIdentifier("showCardSelection", sender: self)
}
}
The recall method I am trying to use may not make sense in it's current iteration as I have been trying many different methods :
#IBOutlet weak var decksListed: UITableView!
let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
var savedDecksClass = [ClassSelection]()
var frc: NSFetchedResultsController = NSFetchedResultsController()
var frcClasses: NSFetchedResultsController = NSFetchedResultsController()
func getFetchedResultsController() -> NSFetchedResultsController {
frc = NSFetchedResultsController(fetchRequest: listFetchRequest(), managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil)
return frc
}
func getClassesFetchedResultsController() -> NSFetchedResultsController {
frcClasses = NSFetchedResultsController(fetchRequest: classFetchRequest(), managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil)
return frcClasses
}
func listFetchRequest() -> NSFetchRequest {
let fetchRequest = NSFetchRequest(entityName: "Deck")
let sortDescriptor = NSSortDescriptor(key: "deckname", ascending: true)
fetchRequest.sortDescriptors = [sortDescriptor]
return fetchRequest
}
func classFetchRequest() -> NSFetchRequest {
let fetchRequestClasses = NSFetchRequest(entityName: "Deck")
let classSortDescriptor = NSSortDescriptor(key: "classname", ascending: true)
fetchRequestClasses.sortDescriptors = [classSortDescriptor]
return fetchRequestClasses
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
let numberofRowsInSection = frc.sections?[section].numberOfObjects
return numberofRowsInSection!
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("usersDeck", forIndexPath: indexPath) as! UITableViewCell
let listed = frc.objectAtIndexPath(indexPath) as! Deck
cell.textLabel?.text = listed.deckname
let listedClass = frcClasses.objectAtIndexPath(indexPath) as! ClassSelection
cell.detailTextLabel!.text = listedClass.classname
return cell
}
func controllerDidChangeContent(controller: NSFetchedResultsController) {
decksListed.reloadData()
}
override func viewDidLoad() {
super.viewDidLoad()
frcClasses = getClassesFetchedResultsController()
frcClasses.delegate = self
frc.performFetch(nil)
frc = getFetchedResultsController()
frc.delegate = self
frc.performFetch(nil)
}
I hope this is enough to give you an idea. I checked the relationships out and they all seem to be correct in the model. I apologize in advanced for the way some of the code looks I plan on shrinking it down after all the editing is done and working.
Thanks to pbasdf for helping me with this one. The chat he opened actually contained exactly what was needed to be done. I just wasn't saving the relationship and passing the object from one view controller to the next. After showing me exactly how to do so with an example I figured out the rest! Basically it would never have been able to recall the object as it never knew that they were related....foolish me! Thanks again!
Related
I'm not getting any errors, just not the result I am looking for.
Here is where I gather data from the user
(If this is not relevant please let me know so I can declutter the post)
I want my custom cell to display the core data record once it's added, but it keeps displaying placeholder labels instead of updating.
class ViewController: UIViewController,UITableViewDataSource, UITableViewDelegate
{
var parties: [NSManagedObject] = []
#IBOutlet weak var tableView: UITableView!
#IBAction func addParty(_ sender: UIBarButtonItem)
{
/*init alert controller with title, message & .alert style*/
let alert = UIAlertController(title: "New Name",
message: "Add a new name",
preferredStyle: .alert)
/*create a name text field, with placeholder "name"*/
alert.addTextField(configurationHandler: { (textFieldName) in
textFieldName.placeholder = "name"
})
/*create a ssn text field, with placeholder "ssn"*/
alert.addTextField(configurationHandler: { (textFieldSize) in
textFieldSize.placeholder = "size"
})
/*create a ssn text field, with placeholder "ssn"*/
alert.addTextField(configurationHandler: { (textFieldContact) in
textFieldContact.placeholder = "contact"
})
/*create a ssn text field, with placeholder "ssn"*/
alert.addTextField(configurationHandler: { (textFieldLocation) in
textFieldLocation.placeholder = "location"
})
/*create a save action*/
let saveAction = UIAlertAction(title: "Save", style: .default) { [unowned self] action in
/*find textfield's text (name) guard let way to get unwrap value otherwise return early*/
guard let textField = alert.textFields?.first,
let nameToSave = textField.text else {
return
}
/*find textfield's text (ssn) guard let way to get unwrap value otherwise return early*/
guard let textFieldSize = alert.textFields?[1],
let sizeToSave = textFieldSize.text else {
return
}
/*find textfield's text (ssn) guard let way to get unwrap value otherwise return early*/
guard let textFieldContact = alert.textFields?[2],
let contactToSave = textFieldContact.text else {
return
}
/*find textfield's text (ssn) guard let way to get unwrap value otherwise return early*/
guard let textFieldLocation = alert.textFields?[3],
let locationToSave = textFieldLocation.text else {
return
}
/*call save method by passing nameToSave and SSNToSave*/
self.save(name: nameToSave, size: sizeToSave, contact: contactToSave, location: locationToSave)
self.tableView.reloadData()
}
let cancelAction = UIAlertAction(title: "Cancel",
style: .default)
alert.addAction(saveAction)
alert.addAction(cancelAction)
present(alert, animated: true)
}
// Save core data function
func save(name: String, size : String, contact: String, location: String)
{
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
return
}
/*1.
Before you can save or retrieve anything from your Core Data store, you first need to get your hands on an NSManagedObjectContext. You can consider a managed object context as an in-memory “scratchpad” for working with managed objects.
Think of saving a new managed object to Core Data as a two-step process: first, you insert a new managed object into a managed object context; then, after you’re happy with your shiny new managed object, you “commit” the changes in your managed object context to save it to disk.
Xcode has already generated a managed object context as part of the new project’s template. Remember, this only happens if you check the Use Core Data checkbox at the beginning. This default managed object context lives as a property of the NSPersistentContainer in the application delegate. To access it, you first get a reference to the app delegate.
*/
let managedContext = appDelegate.persistentContainer.viewContext
/*
An NSEntityDescription object is associated with a specific class instance
Class
NSEntityDescription
A description of an entity in Core Data.
Retrieving an Entity with a Given Name here person
*/
let entity = NSEntityDescription.entity(forEntityName: "Party",
in: managedContext)!
/*
Initializes a managed object and inserts it into the specified managed object context.
init(entity: NSEntityDescription,
insertInto context: NSManagedObjectContext?)
*/
let party = NSManagedObject(entity: entity,
insertInto: managedContext)
/*
With an NSManagedObject in hand, you set the name attribute using key-value coding. You must spell the KVC key (name in this case) exactly as it appears in your Data Model
*/
party.setValue(name, forKeyPath: "name")
party.setValue(size, forKeyPath: "size")
party.setValue(contact, forKeyPath: "contact")
party.setValue(location, forKeyPath: "location")
/*
You commit your changes to person and save to disk by calling save on the managed object context. Note save can throw an error, which is why you call it using the try keyword within a do-catch block. Finally, insert the new managed object into the people array so it shows up when the table view reloads.
*/
do {
try managedContext.save()
parties.append(party)
tableView.reloadData()
} catch let error as NSError {
print("Could not save. \(error), \(error.userInfo)")
}
}
// TABLE VIEW CODE
func tableView(_ tableView: UITableView,
numberOfRowsInSection section: Int) -> Int
{
return parties.count
}
//NEED TO FIX WHY CUSTOM CELL NOT DISPLAYING INFO
func tableView(_ tableView: UITableView,
cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
(print(tableView.dequeueReusableCell(withIdentifier: "PartyCell", for: indexPath)))
let party = parties[indexPath.row] as NSManagedObject
let cell = tableView.dequeueReusableCell(withIdentifier: "PartyCell",
for: indexPath) as! PartyCell
cell.nameLabel?.text = party.value(forKeyPath: "name") as? String
cell.sizeLabel.text = party.value(forKeyPath: "size") as? String
cell.contactLabel.text = party.value(forKeyPath: "contact") as? String
cell.locationLabel.text = party.value(forKeyPath: "location") as? String
return cell
}
override func viewDidLoad()
{
super.viewDidLoad()
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Below I have my existing query download and cell for table row code...
publicDB.perform(query, inZoneWith: nil)
{
(results, error) -> Void in
if (error != nil)
{
self.present(alert, animated: true, completion: nil)
}
else
{
for result in results!
{
self.restaurantArray.append(result)
}
OperationQueue.main.addOperation( { () -> Void in
self.tableView.reloadData()
}) } }}
downloadRestaurants()
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "restaurantcell") as? RestaurantTableCell
let restaurant: CKRecord = restaurantArray[indexPath.row]
cell?.name?.text = restaurant.value(forKey: "Name") as? String
let asset = restaurant.value(forKey: "Picture") as! CKAsset
let data = try! Data(contentsOf: asset.fileURL)
_ = UIImage(data: data)
cell?.picture?.image = UIImage(data: data)
return cell!
}
When I run this code, the app remains functional but scrolling through the 10 or so table cells is incredibly choppy. I am unsure what is causing this - all records, each containing an image, are downloaded during the query download portion of the top function. However, a problem or concept I'm missing is ever present during runtime. What am I missing here? Lazy loading? cache? something else? Unsure at this point, so any help would be incredibly helpful.
Update 1:
I've updated my code with a large thank you going to Pierce. I've had to update my code ever so slightly from his answer to maintain a ckrecord array to segue over to another controller via - restaurantArray but also create a new array for the NSObject class - tablerestaurantarray to be displayed in the current table controller.
var restaurantArray: Array<CKRecord> = []
var tablerestaurantarray: [Restaurant] = []
for result in results!
{
let tablerestaurant = Restaurant()
if let name = result.value(forKey: "Name") as! String? {
tablerestaurant.name = name
}
// Do same for image
if let imageAsset = result.object(forKey: "Picture") as! CKAsset? {
if let data = try? Data(contentsOf: imageAsset.fileURL) {
tablerestaurant.image = UIImage(data: data)
}
}
self.tablerestaurantarray.append(tablerestaurant)
self.restaurantArray.append(result)
}
OperationQueue.main.addOperation( { () -> Void in
self.tableView.reloadData()
})
}
}
}
downloadRestaurants()
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return restaurantArray.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "restaurantcell") as? RestaurantTableCell
let restaurant: Restaurant = tablerestaurantarray[indexPath.row]
cell?.name?.text = restaurant.name
cell?.picture?.image = restaurant.image
return cell!
}
The way your code is setup, whenever you scroll in your UITableView, your program is converting a CKAsset into Data, and then converting that into a UIImage, and that's within every cell! That's a rather inefficient process, so try creating an NSObject called something like Restaurant that has an image property, and when you go through all the records returned from your CKQuery, parse each record into a new Restaurant object. To create a new NSObject, go to File -> New -> File -> select 'Swift File' and add something like this:
import UIKit
class Restaurant: NSObject {
// Create a UIImage property
var image: UIImage?
// Add any other properties, i.e. name, address, etc.
var name: String = ""
}
Now for your query:
// Create an empty array of Restaurant objects
var restaurantArray: [Restaurant] = []
publicDB.perform(query, inZoneWith: nil) { (results, error) -> Void in
if (error != nil) {
self.present(alert, animated: true, completion: nil)
} else {
for result in results! {
// Create a new instance of Restaurant
let restaurant = Restaurant()
// Use optional binding to check if value exists
if let name = result.value(forKey: "Name") as! String? {
restaurant.name = name
}
// Do same for image
if let imageAsset = result.object(forKey: "Picture") as! CKAsset? {
if let data = try? Data(contentsOf: imageAsset.fileURL) {
restaurant.image = UIImage(data: data)
}
}
// Append the new Restaurant to the Restaurants array (which is now an array of Restaurant objects, NOT CKRecords)
self.restaurantArray.append(restaurant)
}
OperationQueue.main.addOperation( { () -> Void in
self.tableView.reloadData()
})
}
}
Now your cell setup is much simpler:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "restaurantcell") as? RestaurantTableCell
let restaurant: Restaurant = restaurantArray[indexPath.row]
cell?.name?.text = restaurant.name
cell?.picture?.image = restaurant.image
return cell!
}
You should use CKQueryOperation in order to implements pagination for your UITableView.
You have to set the resultLimit property to a number equals to the cell quantity visiable at one time on you table plus 3 or 4
Set recordFetchedBlock property where you have to implement the code that will apply to one CKRecord
Set queryCompletionBlock property. This is the most important part on your pagination code because this closure receive an Optional CKQueryCursor parameter.
If this CKQueryCursor is nil then you have reach the last record available for you query but if it's a non nil value, then you have more records to fetch using this CKQueryCursor as indicator to your next fetch.
When user scroll on your TableView and reach the last element you should perform another fetch with CKQueryCursor.
Other performance advice is CKAssets should be treated on separated execution queues.
I am a beginner student in Swift 3 and I am currently studying CoreData. I am trying to do an App where I have a first controller that is a list view (tableviewcontroller) where I can see some students. Inside each cell, I have an image (UIImage) and 4 labels (Strings: name, preceptor, note and date) who fetch data from an Array that keeps the information from the entity "AlunosLista", who has one attribute for each item (image is binary data). I can add these information through another view controller (AddDataVC.swift) and list them perfectly. The app until here is fine. What i cannot do, and i have been trying a lot of things, many things, is to send the data from the row selected (clicked) to another viewcontroller for the detailed view (DetailsVC.swift). When i was using a simple Array, without CoreData, worked fine. But now i cannot do it. Now parts of the code:
File (1): TableviewController
class TabelaListagem: UITableViewController {....
import CoreData
import UIKit
var alunos: [NSManagedObject?] = []
var gerenciadorDeDados: NSManagedObjectContext? = nil
override func viewDidLoad() {
super.viewDidLoad()
//CORE DATA
let AppleObject = UIApplication.shared.delegate as! AppDelegate
gerenciadorDeDados = AppleObject.persistentContainer.viewContext
LoadFetch()
}
(.......)
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let path = alunos[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "celulaReuso", for: indexPath) as! ListagemCelulas
cell.lblAluno.text = path?.value(forKey: "nome") as? String
cell.lblPreceptor.text = path?.value(forKey: "preceptor") as? String
cell.lblData.text = path?.value(forKey: "dataHoje") as? String
cell.lblNotaAluno.text = path?.value(forKey: "nota") as? String
let caminhodaImagem = path?.value(forKey: "fotoAluno")
cell.imgAluno.image = UIImage(data: (caminhodaImagem as? NSData) as! Data)
return cell
}
Here should place the prepare(for segue), that I have tried many ways. This was the last one, who didn't worked too. "Build succeeded", but crashed.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "segueAluno" {
if let pathC = tableView.indexPathForSelectedRow{
let VCDestino = segue.destination as? DescriAluno
let objeto = FecthResultado?.object(at: pathC)
VCDestino?.alunoD = objeto as! NSManagedObject?
}
}
}
File (2) DetailViewController
import UIKit
import CoreData
class DescriAluno: UIViewController {
#IBOutlet weak var imgFotoAluno: UIImageView!
#IBOutlet weak var nomeAluno: UILabel
#IBOutlet weak var txtPreceptor: UILabel!
#IBOutlet weak var txtNotaAluno: UILabel!
#IBOutlet weak var txtDataHoje: UILabel!
var gerenciadorDeDados: NSManagedObjectContext!
var alunoD: NSManagedObject?
override func viewDidLoad() {
super.viewDidLoad()
//CORE DATA
let AppleObject = UIApplication.shared.delegate as! AppDelegate
gerenciadorDeDados = AppleObject.persistentContainer.viewContext
imgFotoAluno.image = alunoD?.value(forKey: "fotoAluno")
nomeAluno.text = alunoD?.value(forKey: "nome")
txtPreceptor.text = alunoD?.value(forKey: "preceptor")
txtNotaAluno.text = alunoD?.value(forKey: "nota")
txtDataHoje.text = alunoD?.value(forKey: "dataHoje")
}
Error message after crash:
Terminating app due to uncaught exception
'NSInvalidArgumentException', reason: 'executeFetchRequest:error:
is not a valid NSFetchRequest.'
I really don't know how to proceed. I have tried so many things, some of them told about NSFetchedResults, but i could write or understand them. If any one could help here, I appreciate. Thank you.
This is the Fetch request (func):
Ok. This is my fetch request:
func LoadFecth() {
let ordenacaoAZ = NSSortDescriptor(key: "nome", ascending: true)
let ordenacaoAZPrecep = NSSortDescriptor(key: "preceptor", ascending: true)
let recupoerardados = NSFetchRequest<NSFetchRequestResult>(entityName: "AlunosLista")
recupoerardados.sortDescriptors = [ordenacaoAZPrecep, ordenacaoAZ]
do{
let recupera = try gerenciadorDeDados?.fetch(recupoerardados)
self.alunos = recupera as! [NSManagedObject]
self.tableView.reloadData()
}catch let erro as NSError{
print("Erro ao carregar: \(erro.description)")
}
}
Your core data life will get easier in every way if you use NSManagedObject subclasses for your entities. This allows you to use convenience accessors to get typed fetch requests and to skip all this value(forKey: stuff and use properties.
The error is that your fetch request is not valid.
You may have mistyped the entity name ("AlunosLista").
It may be getting upset because the type of the fetch request, without a specific NSManagedObject subclass, is actually NSFetchRequest<NSManagedObject>.
The best thing to do is enter a subclass for the entity in the model editor, generate the subclass files, then use this:
let recupoerardados: NSFetchRequest<AlunosLista> = AlunosLista.fetchRequest()
I'm trying to insert a default record into my core data entity while the tableview first-time loaded and checked there's no data in the entity.
The data inserted just fine , but the reloadData() didn't work, after navigate to other view and navigate back to the view the data appears. no matter the reloadData() in or out of the .save() method.
override func viewDidLoad() {
let cateContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
let categoryRequest = NSFetchRequest(entityName: "Category")
categoryArray = (try! cateContext.executeFetchRequest(categoryRequest)) as! [Category]
if categoryArray.count == 0 {
let category = NSEntityDescription.insertNewObjectForEntityForName("Category", inManagedObjectContext: cateContext) as! Category
category.sno = "1"
category.category = "General"
category.locate = false
do {
try cateContext.save()
self.categoryTableView.reloadData()
} catch let saveError as NSError {
print("Saving Error : \(saveError.localizedDescription)")
}
}
//self.categoryTableView.reloadData()
}
If your are calling self.categoryTableView.reloadData() in viewDidLoad() method it will not reload your tableView twice. You need to call self.categoryTableView.reloadData() after you have checked if entity existed again.
I have a UISearchBar thats hooked up to a table view thats populated by Core Data. I've been having a lot of trouble getting filtering to work. Most tutorials on this are extremely old and haven't worked for me. I was thinking about converting the entity to an array and doing the filtering on the array but I've read that that's inefficient. I'm thinking I should use NSPredicate, but I honestly don't know what to do. Any ideas? Thanks.
I've actually been working on a demo of this and I have just put it up on GitHub. It can be found here. As far as the implementation of it goes, you have to set up UITableViewController, NSFetchedResultsController, and UISearchDisplayDelegate for your class:
class ContactsViewController: UITableViewController, NSFetchedResultsController, UISearchDisplayDelegate {
}
And with this there will be two table views:
Your tableView from the tableViewController (self.tableView)
Your tableView from searchDisplayController (searchDisplayController?.searchResultsTableView)
You also make class variables for fetchedResultsController, searchResultsController, appDelegate, and managedObjectContext:
let appDelegate = UIApplication.sharedApplication().delegate as? AppDelegate
var managedObjectContext: NSManagedObjectContext? {
get {
if let delegate = appDelegate {
return delegate.managedObjectContext
}
return nil
}
}
var fetchedResultsController: NSFetchedResultsController?
var searchResultsController: NSFetchedResultsController?
In the viewDidLoad() you must register your cell for your searchResultsTableView because it does not exist in interface:
searchDisplayController?.searchResultsTableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "CellID")
It is also here that you setup your fetchRequest:
fetchedResultsController = NSFetchedResultsController(fetchRequest: someFetchRequest, managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil)
fetchedResultsController?.delegate = self
fetchedResultsController?.performFetch(nil)
You will need a function that returns which FRC you will need depending on the tableView. You make this function return a NSFetchedResultsController and you will use this in all of the table view functions where you pull data from the FRC such as cellForRowAtIndexPath: because it will get you the correct set of data
func fetchedResultsControllerForTableView(tableView: UITableView) -> NSFetchedResultsController? {
return tableView == searchDisplayController?.searchResultsTableView ? searchResultsController? : fetchedResultsController?
}
Finally, you need to implement searchDisplayControllerWillUnloadSearchResults and searchDisplayControllerShouldReloadTableForSearchString:
func searchDisplayController(controller: UISearchDisplayController, willUnloadSearchResultsTableView tableView: UITableView) {
searchResultsController?.delegate = nil
searchResultsController = nil
}
func searchDisplayController(controller: UISearchDisplayController!, shouldReloadTableForSearchString searchString: String!) -> Bool {
let firstNamePredicate = NSPredicate(format: "nameFirst CONTAINS[cd] %#", searchString.lowercaseString)
let lastNamePredicate = NSPredicate(format: "nameLast CONTAINS[cd] %#", searchString.lowercaseString)
let predicate = NSCompoundPredicate.orPredicateWithSubpredicates([firstNamePredicate!, lastNamePredicate!])
searchResultsController = NSFetchedResultsController(fetchRequest: someOtherFetchRequestWithPredicate(predicate), managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil)
searchResultsController?.performFetch(nil)
return true
}
If you have any trouble filling in the other stuff, such as the data model or the NSFetchedResultsControllerDelegate methods, check out the demo!
As of iOS 8, the searchDisplayController is deprecated.