Picking specific Items from Core Data - ios

I have a an entity in core data that represents a workout model. Each entity has a DayID attribute that represents which day the item falls into as shown in the image.
The code to create and save a specific item is shown below in Swift
#IBAction func doneButtonPressed(sender: AnyObject) {
let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let managedObjectContextCreation = appDelegate.managedObjectContext
let entityDescription = NSEntityDescription.entityForName("ExerciseItemModel", inManagedObjectContext: managedObjectContextCreation)
//Sunday
let exerciseItemtoAdd = ExerciseItemModel(entity: entityDescription!, insertIntoManagedObjectContext: managedObjectContextCreation)
exerciseItemtoAdd.dayID = dayName //DayName could be Wednesday
exerciseItemtoAdd.exerciseType = "Cardio"
exerciseItemtoAdd.exerciseName = self.exerciseNameTextField.text!
exerciseItemtoAdd.durationOrSets = durationLabelTextArea.text!
exerciseItemtoAdd.distanceOrReps = distanceLabelTextArea.text!
exerciseItemtoAdd.weight = ""
exerciseItemtoAdd.date = currentDate
appDelegate.saveContext() //Save the elements I just created.
let request: NSFetchRequest = NSFetchRequest(entityName: "ExerciseItemModel")
do {
_ = try managedObjectContextCreation.executeFetchRequest(request)
// success ...
} catch let error as NSError {
// failure
print("Fetch failed: \(error.localizedDescription)")
}
self.dismissViewControllerAnimated(true, completion: nil)
}
I can fetch items specific to a day e.g. Wednesday in cellForRowAtIndexPath using the following code:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let exerciseItem = fetchedResultController.objectAtIndexPath(indexPath) as! ExerciseItemModel
//Check if the DayID is the same as a specific WeekDay e.g. Wednesday
if exerciseItem.dayID == self.weekDayModel.dayName {
//All the code here
}
return Cell!
}
The problem I am hence facing is how do I specify the numbeOfRows in section function to only return the number of items related to a specific dayName. eg. I want only the number of items whose DayID is Wednesday.
At the moment the function return all the entities including those with other dayID's from Sunday to Saturday and hence distorts the TableView.
Here is my numberOfRowsInSection function:
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//let exerciseItem = fetchedResultController.
//if exerciseItem.dayID == self.weekDayModel.dayName {
//}
numberOfExerciseItems = fetchedResultController.sections![section].numberOfObjects
return fetchedResultController.sections![section].numberOfObjects
}
Any thoughts or help is greatly appreciated. :)

You want to add a predicate to your NSFetchRequest like so:
let request: NSFetchRequest = NSFetchRequest(entityName: "ExerciseItemModel")
request.predicate = NSPredicate("dayID == %#",self.weekDayModel.dayName)

Related

UITableView with core data pushing incorrect index and data

I've been struggling with this for several days already. There are similar problems in this website, but not very the same. And I didn't manage to go forward. I will try to simplify it with one variable.
Problem:
After filtering records in UITableView (records are taken from core data) and trying to push data to another viewcontroller, I get unfiltered index for data, so incorrect data is pushed to new view controller.
My code is below:
I set global variable for core data:
var events : [Event] = []
#objc func textFieldDidChange(_ textField: UITextField) {
if searchField.text == "" {
filterAdded = false
} else {
filterAdded = true
let request:NSFetchRequest<Event> = Event.fetchRequest()
let predicate = NSPredicate(format: "name CONTAINS[c] %# AND nearestDate >= %#", searchField.text!, currentCorrectDate! as CVarArg)
request.predicate = predicate
let sortDescriptor = NSSortDescriptor(key: "nearestDate", ascending: true)
request.sortDescriptors = [sortDescriptor]
do {
events = try DatabaseController.getContext().fetch(request)
}
catch {
print("Error: \(error)")
}
mainListOfDates.reloadData()
}
}
}
It is triggered every time some character is added to search field. UITableView name is "mainListOfDates".
This function works properly and calculated only filtered events:
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return events.count }
This function shows all records from core data in UITableView cells:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "eventCell", for: indexPath) as! EventTableViewCell
let event = events[indexPath.row]
cell.eventNameLabel.text = event.value(forKeyPath: "name") as? String
return cell
}
And with "didSelectRowAt" I would like to push filtered or unfiltered (works perfectly with unfiltered) data to new view controller:
let Storyboard = UIStoryboard(name: "Main", bundle: nil)
let eventStoryboard = Storyboard.instantiateViewController(withIdentifier: "EventViewController") as! EventViewController
let cell = tableView.dequeueReusableCell(withIdentifier: "eventCell", for: indexPath) as! EventTableViewCell
eventStoryboard.getEventName = events[indexPath.row].name ?? "nil"
self.navigationController?.pushViewController(eventStoryboard, animated: false) }
How to solve this issue and send filtered correct data to new view controller?
Thanks in advance.

Wait for function to execute first before moving to next line of code

I am using CloudKit in my app and facing problem showing data in table view. In viewDidLoad() I am fetching data from CloudKit database.
Then in table view functions I do CKRecord object count for number of rows.
But count returns 0 to table view and after few seconds returns number of row. Because of this table view does not show the results.
override func viewDidLoad() {
super.viewDidLoad()
loadNewData()
}
func loadNewData() {
self.loadData = [CKRecord]()
let publicData = CKContainer.default().publicCloudDatabase
let qry = CKQuery(recordType: "Transactions", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
qry.sortDescriptors = [NSSortDescriptor(key: "Transaction_ID", ascending: true)]
publicData.perform(qry, inZoneWith: nil) { (results, error) in
if let rcds = results {
self.loadData = rcds
}
if error != nil {
self.showAlert(msg: (error?.localizedDescription)!)
}
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return loadData.count
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell2", for: indexPath) as! ViewAllTransactionsTVCell
let pn = loadData[indexPath.row].value(forKey: "Party_Name") as! String
let amt = loadData[indexPath.row].value(forKey: "Amount") as! String
let nrt = loadData[indexPath.row].value(forKey: "Narattions") as! String
let dt = loadData[indexPath.row].value(forKey: "Trans_Date") as! String
cell.partyNameLabel.text = pn
cell.dateLabel.text = dt
cell.narationLabel.text = nrt
cell.amountLabel.text = amt
return cell
}
You shouldn't wait, but instead trigger the reloading of the data when the perform completion handler is called:
publicData.perform(qry, inZoneWith: nil) { (results, error) in
if let rcds = results {
DispatchQueue.main.async {
self.loadData = rcds
self.tableView.reloadData()
}
}
if error != nil {
self.showAlert(msg: (error?.localizedDescription)!)
}
}
Note, I'm dispatching the reload process to the main queue, because you're not guaranteed to have this run on the main thread. As the documentation says:
Your block must be capable of running on any thread of the app ...
And because UI updates must happen on the main thread (and because you want to synchronize your access to loadData), just dispatch this to the main queue, like above.

How can I sort and show in correct section of a UITableview in swift using CoreData results

Attached at very bottom of this question is my inventory controller file. My problem is I'm getting duplicate results in all the sections. I narrowed down the reason to
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
My code in that function does not account for how many rows there are in each section. As such I'm just printing out the same duplicate results every section.
The actual question is listed after the images below...
Refer to images below:
I also have the ability to change the index from my settings menu so it can index by numbers, like 0-9. Refer to image below:
That said, I currently load the data from Core Data. Attached is reference image of the entities I use and there relationships.
The Question:
My question is, how can I get the results from coreData to be sorted into the A,B,C type sections or 1,2,3 sections so that navigating the table will be simple.
My hunch is the line that says let inventoryRecords = try moc.executeFetchRequest(inventoryFetchRequest) as? [Inventory] needs a sort descriptor to sort based on how I like, but how I then take the data and put into the correct array structure to split into the sections I need...I have no idea.
globals.swift
import Foundation
import CoreData
//Array of Inventory & Store Core Data Managed Objects
var g_inventoryItems = [Inventory]()
var g_storeList = [Store]()
var g_appSettings = [AppSettings]()
var g_demoMode = false
InventoryController.swift
import UIKit
import CoreData
class InventoryController: UIViewController, UISearchBarDelegate, UITableViewDataSource, UITableViewDelegate {
#IBOutlet weak var searchBar: UISearchBar!
#IBOutlet weak var inventoryTable: UITableView!
var numberIndex = ["0","1","2","3","4","5","6","7","8","9"]
var letterIndex = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"]
var moc = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext //convinience variable to access managed object context
// Start DEMO Related Code
func createInventoryDummyData(number: Int) -> Inventory{
let tempInventory = NSEntityDescription.insertNewObjectForEntityForName("Inventory", inManagedObjectContext: moc) as! Inventory
tempInventory.name = "Test Item # \(number)"
tempInventory.barcode = "00000000\(number)"
tempInventory.currentCount = 0
tempInventory.id = number
tempInventory.imageLargePath = "http://website.tech//uploads/inventory/7d3fe5bfad38a3545e80c73c1453e380.png"
tempInventory.imageSmallPath = "http://website.tech//uploads/inventory/7d3fe5bfad38a3545e80c73c1453e380.png"
tempInventory.addCount = 0
tempInventory.negativeCount = 0
tempInventory.newCount = 0
tempInventory.store_id = 1 //belongs to same store for now
//Select a random store to belong to 0 through 2 since array starts at 0
let aRandomInt = Int.random(0...2)
tempInventory.setValue(g_storeList[aRandomInt], forKey: "store") //assigns inventory to one of the stores we created.
return tempInventory
}
func createStoreDummyData(number:Int) -> Store{
let tempStore = NSEntityDescription.insertNewObjectForEntityForName("Store", inManagedObjectContext: moc) as! Store
tempStore.address = "100\(number) lane, Miami, FL"
tempStore.email = "store\(number)#centraltire.com"
tempStore.id = number
tempStore.lat = 1.00000007
tempStore.lng = 1.00000008
tempStore.name = "Store #\(number)"
tempStore.phone = "123000000\(number)"
return tempStore
}
// End DEMO Related Code
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
print("InventoryController -> ViewDidLoad -> ... starting inits")
//First check to see if we have entities already. There MUST be entities, even if its DEMO data.
let inventoryFetchRequest = NSFetchRequest(entityName: "Inventory")
let storeFetchRequest = NSFetchRequest(entityName: "Store")
do {
let storeRecords = try moc.executeFetchRequest(storeFetchRequest) as? [Store]
if(storeRecords!.count<=0){
g_demoMode = true
print("No store entities found. Demo mode = True. Creating default store entities...")
var store : Store //define variable as Store type
for index in 1...3 {
store = createStoreDummyData(index)
g_storeList.append(store)
}
}
let inventoryRecords = try moc.executeFetchRequest(inventoryFetchRequest) as? [Inventory]
if(inventoryRecords!.count<=0){
g_demoMode = true
print("No entities found for inventory. Demo mode = True. Creating default entities...")
var entity : Inventory //define variable as Inventory type
for index in 1...20 {
entity = createInventoryDummyData(index)
g_inventoryItems.append(entity)
}
print("finished creating entities")
}
}catch{
fatalError("bad things happened \(error)")
}
print("InventoryController -> viewDidload -> ... finished inits!")
}
override func viewWillAppear(animated: Bool) {
print("view appearing")
//When the view appears its important that the table is updated.
//Look at the selected Store & Use the LIST of Inventory Under it.
inventoryTable.reloadData()//this is important to update correctly for changes that might have been made
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
print("inventoryItemControllerPrepareForSegueCalled")
if segue.identifier == "inventoryInfoSegue" {
let vc = segue.destinationViewController as! InventoryItemController
if let cell = sender as? InventoryTableViewCell{
vc.inventoryItem = cell.inventoryItem! //sets the inventory item accordingly, passing its reference along.
}else{
print("sender was something else")
}
}
}
func tableView(tableView: UITableView, sectionForSectionIndexTitle title: String, atIndex index: Int) -> Int {
//This scrolls to correct section based on title of what was pressed.
return letterIndex.indexOf(title)!
}
func sectionIndexTitlesForTableView(tableView: UITableView) -> [String]? {
//Use correct index on the side based on settings desired.
if(g_appSettings[0].indextype=="letter"){
return letterIndex
}else{
return numberIndex
}
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//TODO: Need to figure out how many rows for ...column A,B,C or 1,2,3 based on indexType using~
//To do this we need to organize the inventory results into a section'ed array.
if(g_appSettings[0].selectedStore != nil){
return (g_appSettings[0].selectedStore?.inventories!.count)! //number of rows is equal to the selected stores inventories count
}else{
return g_inventoryItems.count
}
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("InventoryTableCell", forIndexPath: indexPath) as! InventoryTableViewCell
if(g_appSettings[0].selectedStore != nil){
//Get the current Inventory Item & Set to the cell for reference.
cell.inventoryItem = g_appSettings[0].selectedStore?.inventories?.allObjects[indexPath.row] as! Inventory
}else{
//This only happens for DEMO mode or first time.
cell.inventoryItem = g_inventoryItems[indexPath.row]//create reference to particular inventoryItem this represents.
}
cell.drawCell() //uses passed inventoryItem to draw it's self accordingly.
return cell
}
func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
if(g_appSettings[0].indextype == "letter"){
return letterIndex[section]
}else{
return numberIndex[section]
}
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
if(g_appSettings[0].selectedStore != nil){
if(g_appSettings[0].indextype=="letter"){
return letterIndex.count
}else{
return numberIndex.count
}
}else{
return 1//only one section for DEMO mode.
}
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
//dispatch_async(dispatch_get_main_queue()) {
//[unowned self] in
print("didSelectRowAtIndexPath")//does not recognize first time pressed item for some reason?
let selectedCell = self.tableView(tableView, cellForRowAtIndexPath: indexPath) as? InventoryTableViewCell
self.performSegueWithIdentifier("inventoryInfoSegue", sender: selectedCell)
//}
}
#IBAction func BarcodeScanBarItemAction(sender: UIBarButtonItem) {
print("test of baritem")
}
#IBAction func SetStoreBarItemAction(sender: UIBarButtonItem) {
print("change store interface")
}
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
print("text is changing")
}
func searchBarCancelButtonClicked(searchBar: UISearchBar) {
print("ended by cancel")
searchBar.text = ""
searchBar.resignFirstResponder()
}
func searchBarSearchButtonClicked(searchBar: UISearchBar) {
print("ended by search")
searchBar.resignFirstResponder()
}
func searchBarTextDidEndEditing(searchBar: UISearchBar) {
print("ended by end editing")
searchBar.resignFirstResponder()
}
#IBAction func unwindBackToInventory(segue: UIStoryboardSegue) {
print("unwind attempt")
let barcode = (segue.sourceViewController as? ScannerViewController)?.barcode
searchBar.text = barcode!
print("barcode="+barcode!)
inventoryTable.reloadData()//reload the data to be safe.
}
}
//Extention to INT to create random number in range.
extension Int
{
static func random(range: Range<Int> ) -> Int
{
var offset = 0
if range.startIndex < 0 // allow negative ranges
{
offset = abs(range.startIndex)
}
let mini = UInt32(range.startIndex + offset)
let maxi = UInt32(range.endIndex + offset)
return Int(mini + arc4random_uniform(maxi - mini)) - offset
}
}
Update:: **
So I was looking around and found this article (I implemented it).
https://www.andrewcbancroft.com/2015/03/05/displaying-data-with-nsfetchedresultscontroller-and-swift/
I'm really close now to figuring it out. Only problem is I can get it to auto create the sections, but only on another field, like for example store.name, I can't get it to section it into A,B,C sections or 1,2,3.
This is my code for the fetchedResultsController using the methods described in that article.
//Create fetchedResultsController to handle Inventory Core Data Operations
lazy var fetchedResultsController: NSFetchedResultsController = {
let inventoryFetchRequest = NSFetchRequest(entityName: "Inventory")
let primarySortDescriptor = NSSortDescriptor(key: "name", ascending: true)
let secondarySortDescriptor = NSSortDescriptor(key: "barcode", ascending: true)
inventoryFetchRequest.sortDescriptors = [primarySortDescriptor, secondarySortDescriptor]
let frc = NSFetchedResultsController(
fetchRequest: inventoryFetchRequest,
managedObjectContext: self.moc,
sectionNameKeyPath: "store.name",
cacheName: nil)
frc.delegate = self
return frc
}()
Question is what to put for sectionNameKeyPath: now that will make it section it on A B C and I got this !
Found a stackoverflow post very similar to my issue, but need swift answer.
A-Z Index from NSFetchedResultsController with individual section headers within each letter?
Here is another similar article but all objective-c answers.
NSFetchedResultsController with sections created by first letter of a string
Update::
Found another article I think with my exact issue (How to have a A-Z index with a NSFetchedResultsController)
Ok I figured it out, phew was this confusing and took a lot of research.
Okay, so first thing you have to do is create a transient property on the data model. In my case I called it lettersection. To do this in the entity just create a new attribute and call it lettersection and in graph mode if you select it (double click it), you will see option in inspector for 'transient'. This means it won't be saved to the database and is used more for internal reasons.
You then need to manually set up the variable in the extension area of the model definition. Here is how it looks for me.
import Foundation
import CoreData
extension Inventory {
#NSManaged var addCount: NSNumber?
#NSManaged var barcode: String?
#NSManaged var currentCount: NSNumber?
#NSManaged var id: NSNumber?
#NSManaged var imageLargePath: String?
#NSManaged var imageSmallPath: String?
#NSManaged var name: String?
#NSManaged var negativeCount: NSNumber?
#NSManaged var newCount: NSNumber?
#NSManaged var store_id: NSNumber?
#NSManaged var store: Store?
var lettersection: String? {
let characters = name!.characters.map { String($0) }
return characters[0].uppercaseString
}
}
Once you do this, you simply call this new 'lettersection' with the fetchedResultsController like so...
let frc = NSFetchedResultsController(
fetchRequest: inventoryFetchRequest,
managedObjectContext: self.moc,
sectionNameKeyPath: "lettersection",
cacheName: nil)
and everything will work! It sorts by the name of my inventory items, but groups them by the first letters, for a nice A,B,C type list!
"My question is, how can I get the results from coreData to be sorted into the A,B,C type sections or 1,2,3 sections so that navigating the table will be simple."
Using "Store" as your entity and property "name" to be what you want to sort the records by.
override func viewDidLoad() { super.viewDidLoad()
let fetchRequest = NSFetchRequest()
let entity = NSEntityDescription.entityForName("Store", inManagedObjectContext: managedObjectContext)
fetchRequest.entity = entity
let sortDescriptor = NSSortDescriptor(key: "name", ascending: true)
fetchRequest.sortDescriptors = [sortDescriptor]
do {
let foundObjects = try managedObjectContext.executeFetchRequest(fetchRequest)
locations = foundObjects as! [Location]
} catch {
fatalCoreDataError(error) }
}
You are going to use this function to set the number of sections:
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return letterindex.count // if that is how you want to construct sections
}
I learned this from the Ray Wenderlich e-book "iOS Apprentice". From Lesson 3 - MyLocations. Highly recommend this and their e-book book on CoreData.

How to get data from CloudKit before loading TableData

I'm writing an app in Swift where the first scene has a TableView, I have it setup to display the title and it works fine, I also have it setup to count occurrences in a CloudKit database(or whatever its called) but it performs the count in async so the table defaults to show 0 in the detail pane.
I need to know how to make the app wait before it sets the value for the right detail until the count is completed or how to change them afterwards.
I have attached the code I used to perform the count etc, if I am doing this wrong or inefficiently please let me know
override func viewDidLoad() {
super.viewDidLoad()
self.navigationItem.hidesBackButton = true;
self.textArray.addObject("Link 300")
self.textArray.addObject("Link 410")
self.textArray.addObject("Link 510")
let container = CKContainer.defaultContainer()
let publicData = container.publicCloudDatabase
let query = CKQuery(recordType: "Inventory", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
publicData.performQuery(query, inZoneWithID: nil){results, error in
if error == nil {
for res in results {
let record: CKRecord = res as! CKRecord
if(record.objectForKey(("TrackerModel")) as! String == "Link 300"){
self.count300 = self.count300++
}else if(record.objectForKey(("TrackerModel")) as! String == "Link 410"){
self.count410 = self.count410++
}else if(record.objectForKey(("TrackerModel")) as! String == "Link 510"){
self.count510 = self.count510++
}
}
}else{
println(error)
}
}
self.detailArray.addObject(self.count300.description)
self.detailArray.addObject(self.count410.description)
self.detailArray.addObject(self.count510.description)
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.textArray.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) ->UITableViewCell {
var cell: UITableViewCell = self.tableView.dequeueReusableCellWithIdentifier("cell") as! UITableViewCell
cell.textLabel?.text = self.textArray.objectAtIndex(indexPath.row) as? String
cell.detailTextLabel?.text = self.detailArray.objectAtIndex(indexPath.row) as? String
return cell
}
Many thanks - Robbie
The closure associated with the performQuery will complete asynchronously - that is after viewDidLoad has finished. You need to make sure that you reload your table view once the query has completed and you have the data. You also have a problem because you are updating your totals outside the closure - this code will also execute before the data has loaded.
Finally, make sure that any update to the UI (such as reloading the table view) is dispatched on the main queue
override func viewDidLoad() {
super.viewDidLoad()
self.navigationItem.hidesBackButton = true;
self.textArray.addObject("Link 300")
self.textArray.addObject("Link 410")
self.textArray.addObject("Link 510")
let container = CKContainer.defaultContainer()
let publicData = container.publicCloudDatabase
let query = CKQuery(recordType: "Inventory", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
publicData.performQuery(query, inZoneWithID: nil){results, error in
if error == nil {
for res in results {
let record: CKRecord = res as! CKRecord
if(record.objectForKey(("TrackerModel")) as! String == "Link 300"){
self.count300++
}else if(record.objectForKey(("TrackerModel")) as! String == "Link 410"){
self.count410++
}else if(record.objectForKey(("TrackerModel")) as! String == "Link 510"){
self.count510++
}
}
self.detailArray.addObject(self.count300.description)
self.detailArray.addObject(self.count410.description)
self.detailArray.addObject(self.count510.description)
dispatch_async(dispatch_get_main_queue(), { () -> Void in
self.tableView.reloadData()
})
}else{
println(error)
}
}
}

iOS Swift - How to store array with Core Data?

I'm new to iOS development and was wanting to know which data type I should specify to store multiple strings (array). The app is to do with food and I need to store multiple ingredients as one attribute.
I was thinking of making ingredient as entity, but I just want to make it easy for a starter.
I have read about transformable type but people don't seem to recommend using it to store arrays.
Warning: opinionated answer ahead.
You don't.
Storing things in an array does not make anything easier for you. On the contrary, it will make things much harder just an hour in. Imagine you want to show all Recipes that contain a selected Ingredient. That wouldn't be easy with your array hack, with a proper model it's only a couple line of code.
I would recommend to use a good old relationship with a "Join-entity".
Yes, this is more complicated than hacking something together that barely works. But it's the correct way.
What you was thinking of is exactly what you should do. Core Data is made to store values in array like structure. You should create entity Ingredients and connect your Food entity (or whatever you would like to call it) with relationship with Ingredients entity.
there is a way. You can do each element manually e.g.
You have your array:
let employee: NSMutableArray = []
employee.addObject(["name":"Bill","LastName":"Hanks"])
employee.addObject(["name":"Rolex","LastName":"Swarzer"])
employee.addObject(["name":"Clive","LastName":"Martin"])
employee.addObject(["name":"Jimi","LastName":"Hendrix"])
Assuming you have created your coreData with Entity "Employee" and Attributes "name" and "lastname" you do the following to add it in...
let appDel = UIApplication.sharedApplication().delegate as! AppDelegate
let context = appDel.managedObjectContext
for item in employee {
do {
let newUser = NSEntityDescription.insertNewObjectForEntityForName("Employee", inManagedObjectContext: context)
newUser.setValue(item["name"], forKey: "name")
newUser.setValue(item["LastName"], forKey: "lastname")
try context.save()
} catch {
//do nothing
}
You can then fetch all elements using your fetch request or the NSFetched Results Controller
I have done in Swift 4,
Storing more Arrays into allDataArray (One Array). Fetching array objects from CoreData (AllData) and Displaying in TableView
import UIKit
import Foundation
import CoreData
class ViewController: UIViewController {
var allTableDataArray : [AllData] = [AllData]()
let allDataArray : NSMutableArray = []
var listOfArray1 = ["#849578", "#849302"]
var listOfArray2 = ["Vasuki Shiv", "Prathap Dusi"]
override func viewDidLoad() {
super.viewDidLoad()
saveAllDataToCoredata()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(true)
fetchAllDataFromCoredata()
}
func saveAllDataToCoredata() {
deleteAllData(entity: "AllData")
let context = PersistenceSerivce.context
allDataArray.add(["requestNo" : listOfArray1[0], "vendorName" : listOfArray2[0]])
allDataArray.add(["requestNo" : listOfArray1[1] , "vendorName" : listOfArray2[1]])
for item in (allDataArray){
do {
let newUser = NSEntityDescription.insertNewObject(forEntityName: "AllData", into: context)
guard let requestNoNew = item as? [String:Any] else {
return
}
let requestNoStr = requestNoNew["requestNo"] as! String
newUser.setValue(requestNoStr, forKey: "requestNo")
guard let vendorNameNew = item as? [String:Any] else {
return
}
let vendorNameStr = vendorNameNew["vendorName"] as! String
newUser.setValue(vendorNameStr, forKey: "vendorName")
PersistenceSerivce.saveContext()
try context.save()
} catch {
//do nothing
}
}
}
func fetchAllDataFromCoredata(){
let context = PersistenceSerivce.context
let fetchRequest = NSFetchRequest<AllData>(entityName: "AllData")
allTableDataArray.removeAll()
do {
allTableDataArray = try context.fetch(fetchRequest)
} catch {
print("Unable to fetch from Coredata", error)
}
}
func deleteAllData(entity: String) {
let managedContext = PersistenceSerivce.context
let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: entity)
fetchRequest.returnsObjectsAsFaults = false
do
{
let results = try managedContext.fetch(fetchRequest)
for managedObject in results
{
let managedObjectData:NSManagedObject = managedObject as! NSManagedObject
managedContext.delete(managedObjectData)
}
} catch let error as NSError {
print("Delete all data in \(entity) error : \(error) \(error.userInfo)")
}
}
}
//MARK:- UITableView
extension ViewController : UITableViewDelegate, UITableViewDataSource {
func tableView(_ tableView: UITableView,
heightForRowAt indexPath: IndexPath) -> CGFloat {
return 44
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return (allTableDataArray.count)
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: “TableViewCellID”) as? TableViewCell
let allData = allTableDataArray[indexPath.row]
cell?.requestNoLabel.text = allData.requestNo
cell?.vendorNameLabel.text = allData.vendorName
return cell!
}
}

Resources