The code below checks Parse to see if an email address has been verified. I am able to retrieve the object ID from Core Data (I saved it in a previous view controller) but when it comes to query.getObjectInBackgroundWithId(userID), userID is for some reason nil. I get the error:
Error: no results matched the query (Code: 101, Version: 1.6.0)
import UIKit
import CoreData
class HomePage: UIViewController{
#IBOutlet var emailMessage: UILabel!
//var userID: String!
override func viewDidLoad() {
super.viewDidLoad()
var appDel:AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
var context:NSManagedObjectContext = appDel.managedObjectContext!
var request = NSFetchRequest(entityName: "Users")
request.returnsObjectsAsFaults = false
var results: NSArray = context.executeFetchRequest(request, error: nil)!
var res = results [0] as NSManagedObject
var userID = res.valueForKey("userID") as String
println (userID) //Correct ID is retrieved here
var query = PFQuery(className:"User")
query.getObjectInBackgroundWithId(userID) { //ID becomes nil
(email: PFObject!, error: NSError!) -> Void in
if error == nil {
let checkEmail = email["emailVerified"] as Bool
if (checkEmail != true)
{
self.emailMessage.hidden = false
}
else
{
self.emailMessage.hidden = true
}
}
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
I think the problem lies in the way you're getting a PFQuery for the user. You should use the special user query:
var query = PFUser.query()
See Users - Querying, in the Parse docs.
The User table (as well as all other parse-managed classes) in parse is prefixed by underscore, so you should fix this line:
var query = PFQuery(className:"_User")
Related
I'm trying to load data from the firebase. I successfully load the data like usename and email, but somehow it fails to load the image. I'm attaching my code which I have used to load the data from firebase. Please help. thank you.
code :
import UIKit
import FirebaseDatabase
import Firebase
class ProfileVC: UIViewController {
#IBOutlet weak var currentphoto: UIImageView!
#IBOutlet weak var usernameLabel: UILabel!
#IBOutlet weak var BioOrEmailLabel: UILabel!
var databasereff : DatabaseReference!
override func viewDidLoad() {
super.viewDidLoad()
databasereff = Database.database().reference()
if let userid = Auth.auth().currentUser?.uid
{
databasereff.child("users").child(userid).observeSingleEvent(of: .value, with: { (snapshot) in
let dict = snapshot.value as? [String:Any]
let username = dict?["username"] as? String
let email = dict?["email"] as? String
if let photourl = dict?["profileimageUrl"] as? String
{
let url = URL(string: photourl)
URLSession.shared.dataTask(with: url!, completionHandler: { (data, response, error) in
if error != nil{
print(error?.localizedDescription)
return
}
OperationQueue.main.addOperation {
self.currentphoto.image = UIImage(data: data!)
}
}).resume()
}
self.usernameLabel.text = username
self.BioOrEmailLabel.text = email
})
{
(error) in
print(error.localizedDescription)
}
}
// Do any additional setup after loading the view.
}
}
You need to create FIRStorage reference to retrieve files from Firebase Data Base.
First:
import FirebaseStorage
Second take a storage reference:
var storage: FIRStorage!
Then Initialize it
storage = FIRStorage.storage()
Now:
let dbRef = database.reference().child("myFiles")
dbRef.observeEventType(.ChildAdded, withBlock: { (snapshot) in
// Get download URL from snapshot
let downloadURL = snapshot.value() as! String
// Create a storage reference from the URL
let storageRef = storage.referenceFromURL(downloadURL)
// Download the data, assuming a max size of 1MB (you can change this as necessary)
storageRef.dataWithMaxSize(1 * 1024 * 1024) { (data, error) -> Void in
// Create a UIImage, add it to the array
let pic = UIImage(data: data)
picArray.append(pic)
})
})
In your case path is different so just change the path and Cheers!
Reference: from here
I was just wondering how would I be able to use a searched barcode to fetch using Core Data in Swift. I'm basically passing a barcode to a static func method, but how would I be able to use that to fetch the data from the Core Data?
Here is the barcode when detected:
func barcodeDetected(code: String) {
// Let the user know we've found something.
let alert = UIAlertController(title: "Found a Barcode!", message: code, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Search", style: UIAlertActionStyle.Destructive, handler: { action in
// Remove the spaces.
let trimmedCode = code.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceCharacterSet())
// EAN or UPC?
// Check for added "0" at beginning of code.
let trimmedCodeString = "\(trimmedCode)"
var trimmedCodeNoZero: String
if trimmedCodeString.hasPrefix("0") && trimmedCodeString.characters.count > 1 {
trimmedCodeNoZero = String(trimmedCodeString.characters.dropFirst())
// Send the doctored barcode
ProductDetailsViewController.searchCode(trimmedCodeNoZero)
} else {
// Send the doctored barcode
ProductDetailsViewController.searchCode(trimmedCodeString)
}
self.navigationController?.popViewControllerAnimated(true)
}))
self.presentViewController(alert, animated: true, completion: nil)
}
My Product Class:
import UIKit
import Foundation
import CoreData
class ProductDetailsViewController: UIViewController, NSFetchedResultsControllerDelegate {
#IBOutlet weak var productLabel: UILabel!
#IBOutlet weak var priceLabel: UILabel!
#IBAction func addProduct(sender: AnyObject) {
let AppDel = UIApplication.sharedApplication().delegate as? AppDelegate
let context:NSManagedObjectContext = (AppDel?.managedObjectContext)!
let ent = NSEntityDescription.entityForName("Products", inManagedObjectContext: context)
var newProduct = ProductItem(entity: ent!, insertIntoManagedObjectContext: context)
newProduct.title = productLabel.text
//newProduct.price = priceLabel.text
/*context.save(nil)
print(newProduct)
print("Object Saved")*/
}
private(set) var PRODUCT_NAME = ""
private(set) var PRODUCT_PRICE = ""
private var menuItems:[ProductItem] = []
static func searchCode(codeNumber: String) -> String{
let barcodeNumber = codeNumber
return barcodeNumber
}
deinit{
NSNotificationCenter.defaultCenter().removeObserver(self)
}
override func viewDidLoad() {
super.viewDidLoad()
productLabel.text = "Scan a Product"
priceLabel.text = ""
NSNotificationCenter.defaultCenter().addObserver(self, selector: "setLabels:", name: "ProductNotification", object: nil)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
I already added the items into Core Data successfully and was able to load all items into a table in my app. Now with the barcode scanned I want to be able to just load the products with the barcode and i'm stuck on that part. As you can see my static fun searchCode is receiving the barcode from barcodeDetected but what should I do next to fetch it? Thanks.
EDIT:
Core Data Entity
import Foundation
import CoreData
#objc(ProductItem)
class ProductItem: NSManagedObject{
#NSManaged var barcodeNum:String?
#NSManaged var box_height:NSNumber?
#NSManaged var box_length:NSNumber?
#NSManaged var box_width:NSNumber?
#NSManaged var price:NSNumber?
#NSManaged var sku:String?
#NSManaged var weight:NSNumber?
#NSManaged var title:String?
}
To fetch the correct ProductItem, you need to use a predicate (see the Apple Documentation here). In your case, you could use something like this:
let AppDel = UIApplication.sharedApplication().delegate as? AppDelegate
let context:NSManagedObjectContext = (AppDel?.managedObjectContext)!
let fetchRequest = NSFetchRequest(entityName: "ProductItem")
fetchRequest.predicate = NSPredicate(format: "barcodeNum == %#",codeNumber)
let results = try! context.executeFetchRequest(fetchRequest) as! [ProductItem]
if results.count > 0 { // great, you found (at least one) matching item
let scannedProduct = results[0]
// from here you can access the attributes of the product
// such as title, price, sku, etc.
...
} else { // not found
...
}
Note that I've use try! for brevity, but in practice you should use proper do ... catch syntax and handle any errors.
I'm not clear why you are using a static func in the ProductDetailsViewController; a common approach would be to use the above fetch within your barcodeDetected method, and then to segue to the ProductDetailsViewController passing the relevant ProductItem for display/editing or whatever. Or to display an alert view if the product was not found.
import UIKit
import Parse
class HomePageViewController: UIViewController, UITableViewDelegate {
#IBOutlet weak var homPageTableView: UITableView!
var imageFiles = [PFFile]()
var imageText = [String]()
override func viewDidLoad() {
super.viewDidLoad()
// DO any additional setup after loading the view
var query = PFQuery(className: "Posts")
query.orderByAscending("createdAt")
query.findObjectsInBackgroundWithBlock {
(posts : [AnyObject]?, error : NSError?) -> Void in
if error == nil {
//success fetxhing objects
println(posts?.count)
for post in posts! {
self.imageFiles.append(post["imageFile"] as! PFFile) ---------error here
self.imageText.append(post["imageText"] as! String)
}
println(self.imageFiles.count)
}else{ println(error)
}
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
As a title, It is keep saying "unexpectedly found nil while unwrapping an Optional value" at the line I draw.
There are a lot of questions about this, it is hard to read code for me, And even if I undertood, mine didn't go right.
where should I use optional binding?
And can u explain it with really easy example what is optional binding?
Thank you
Your post dictionary does not contain an imageFile key. When you access a dictionary using post["imageFile"] the result is the value (if the key exists) and nil (if the key does not exist). You can distinguish between these cases using
if let imageFile = post["imageFile"],
let imageText = post["imageText"] {
self.imageFiles.append(imageFile as! PFFile)
self.imageText.append(imageText as! String)
} else {
print("imageFile and/or imageText missing from \(post)")
}
You need to unwrap your posts before looping through them because posts: [AnyObject]? is optional.
if error == nil {
if let postData = posts{
//success fetxhing objects
println(postData?.count)
for post in postData! {
self.imageFiles.append(post["imageFile"] as! PFFile)
self.imageText.append(post["imageText"] as! String)
}
println(self.imageFiles.count)
}
}else{
println(error)
}
I am making a tiny quiz app to help my students study for tests. I have the questions on parse.com and successfully can query objects by their ID one at a time, but I end up having to hard code all the objectIds, and what I would like to do is grab the objectIds, put them into an array, and then pull a random question/objectID from that array as the students click through the questions.
I'm a novice, so ... while I may be able to understand the logic, I'm not sure how to write the code.
Here is the code I'm currently using ... but it doesn't include my failed attempts to put the object IDs in an array. I've been trying to add a function CallIDs() with a parse query to get them all, but so far ... no luck. Any ideas?
import UIKit
import Parse
class ViewController: UIViewController {
var ObjectIDs : [String]!
var Question : String!
var Answers : [String]!
var Answer : String!
#IBOutlet var QuestionLabel: UILabel!
#IBOutlet var Button1: UIButton!
#IBOutlet var Button2: UIButton!
#IBOutlet var Button3: UIButton!
#IBOutlet var Button4: UIButton!
#IBOutlet var AnswerResult: UILabel!
#IBOutlet var Next: UIButton!
#IBOutlet var QuizInstructions: UILabel!
var RandomID = 0
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
Hide()
CallData()
}
func GetRandomObjectID() {
ObjectIDs = ["jr92lfjbQc","r0C8oC4aJ6","XbTTX8xBRf","cjV2z4PSvV","wATbbu0JoX","9Y6HzfeeoD","mNHCMaao41","5qRcqyyXOL","JaLCoeyA1T","nrnifGOP1T","aDAQ6t3saJ","jKF0ZhmPxh"]
RandomID = Int (arc4random_uniform(UInt32(ObjectIDs.count)))
}
func CallData() {
GetRandomObjectID()
var query : PFQuery = PFQuery(className: "QuestionsandAnswers")
query.getObjectInBackgroundWithId(ObjectIDs[RandomID]) {
(ObjectHolder : PFObject!, error : NSError!) -> Void in
if (error == nil) {
self.Question = ObjectHolder ["Question"] as String!
self.Answers = ObjectHolder ["Answers"] as Array!
self.Answer = ObjectHolder ["Answer"] as String!
if (self.Answers.count > 0) {
self.QuestionLabel.text = self.Question
self.Button1.setTitle(self.Answers[0], forState: UIControlState.Normal)
self.Button2.setTitle(self.Answers[1], forState: UIControlState.Normal)
self.Button3.setTitle(self.Answers[2], forState: UIControlState.Normal)
self.Button4.setTitle(self.Answers[3], forState: UIControlState.Normal)
}
} else {
NSLog("Something is wrong, dude. Sorry.")
}
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func Hide() {
AnswerResult.hidden = true
Next.hidden = true
}
func UnHide() {
AnswerResult.hidden = false
Next.hidden = false
}
#IBAction func Button1Action(sender: AnyObject) {
UnHide()
if (Answer == "0") {
AnswerResult.text = "Woot! That's correct!"
} else {
AnswerResult.text = "Nope. Try Again."
}
}
#IBAction func Button2Action(sender: AnyObject) {
UnHide()
if (Answer == "1") {
AnswerResult.text = "Woot! That's correct!"
} else {
AnswerResult.text = "Nope. Try Again."
}
}
#IBAction func Button3Action(sender: AnyObject) {
UnHide()
if (Answer == "2") {
AnswerResult.text = "Woot! That's correct!"
} else {
AnswerResult.text = "Nope. Try Again."
}
}
#IBAction func Button4Action(sender: AnyObject) {
UnHide()
if (Answer == "3") {
AnswerResult.text = "Woot! That's correct!"
} else {
AnswerResult.text = "Nope. Try Again."
}
}
#IBAction func Next(sender: AnyObject) {
CallData()
Hide()
}
}
///// well ... here is the function I attempted to code, but it isn't working:
func CallIDs() {
var query = PFQuery(className: “QuestionsandAnswers”)
query.findObjectsInBackgroundWithBlock {
(objects: [AnyObject]!, error: NSError!) -> Void in
for object in objects {
self.objectIdsArray.append(object.objectId)
}
}
}
I think the underlying misunderstanding in this question is that objects are to be retrieved using their ids. The requirement is for a random object, and that can be achieved better by knowing only the count of the objects stored on the server.
Getting the count we can select a random object by setting a random skip for a query. So, in the completion block of countObjectsInBackgroundWithBlock, get a random number up to that count like this:
let randomSkip = arc4random_uniform(count)
Now we're ready to do a query with no object id, setting query.skip = randomSkip, and query.limit = 1.
EDIT - If I were to build this in Objective-C, I would do it as follows:
- (void)randomQuestion:(void (^)(NSString *question, NSArray *answers))completion {
PFQuery *countQuery = [PFQuery queryWithClassName:#"QuestionsandAnswers"];
[countQuery countObjectsInBackgroundWithBlock:^(int count, NSError *error) {
NSInteger randomSkip = arc4random_uniform(count);
PFQuery *query = [PFQuery queryWithClassName:#"QuestionsandAnswers"];
query.skip = randomSkip;
query.limit = 1;
[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
if (!error) {
if (objects.count) {
PFObject *questionAndAnswerObject = objects[0];
NSString *question = questionAndAnswerObject[#"Question"];
NSArray *answers = questionAndAnswerObject[#"Answers"];
completion(question, answers);
} else {
NSLog(#"no error, but no Q&A objects found");
}
} else {
NSLog(#"there was an error %#", error);
completion(nil, nil);
}
}];
}];
}
I am not sure where you declare the array objectIdsArray. I was unable to find it. However the reason you may be having trouble replacing an existing array is because the function you are calling, findObjectsInBackgroundWithBlock does not run on the main thread. The code will continue to execute rather then waiting for the objectIds to download.
In order to make sure that you have downloaded the objectIds first before you try to use them, you may want to use the following code:
func CallIDs() {
var query = PFQuery(className: “QuestionsandAnswers”)
query.selectKeys(["objectId"])
self.objectIdsArray = query.findObjects()
}
Note: When run, you should see the following message:
Warning: A long-running operation is being executed on the main thread.
However I have not yet found this to be a problem. If the download is quick, it should not be noticeable. If it is taking a considerable amount of time, you can add in a UIActivityIndicatorView.
I know this is a duplicate of other questions but I've followed the answers to those questions and I still get the same error.
I think the error is coming from the fact that the code is trying to fetch the data when it has not even been saved (there is a delay in saving the data because I am getting it from Parse). Any ideas?
The exact error I get is:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'NSFetchRequest could not locate an NSEntityDescription for entity name 'emailStatus''
-
import UIKit
import CoreData
class RegisterEmail: UIViewController {
var test1: Bool?
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func shouldPerformSegueWithIdentifier(identifier: String!, sender: AnyObject!) -> Bool {
if identifier == "passEmail" {
var query = PFUser.query()
query.getObjectInBackgroundWithId("vFu93HatwL") {
(User: PFObject!, error: NSError!) -> Void in
if error == nil {
NSLog("%#", User)
var checkEmail = User["emailVerified"] as Bool
println(checkEmail)
var appDel:AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
var context:NSManagedObjectContext = appDel.managedObjectContext!
var newEmail = NSEntityDescription.insertNewObjectForEntityForName("Email", inManagedObjectContext: context) as NSManagedObject
newEmail.setValue(checkEmail, forKey: "emailStatus")
context.save(nil)
println (newEmail)
println("Object Saved")
} else {
NSLog("%#", error)
}
}
var appDel:AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
var context:NSManagedObjectContext = appDel.managedObjectContext!
var request = NSFetchRequest(entityName: "emailStatus")
request.returnsObjectsAsFaults = false
var results: NSArray = context.executeFetchRequest(request, error: nil)!
if(results.count > 0)
{
var res = results [0] as NSManagedObject
test1 = res.valueForKey("emailStatus") as Bool
}
if (test1 == false) {
let alert = UIAlertView()
alert.title = "Error"
alert.message = "The email you have provided has not been verified."
alert.addButtonWithTitle("Dismiss")
alert.show()
return false
}
else {
return true
}
}
// by default, transition
return false
}
}
from op: "...everything is set up in the database file. Entity is called email and the attribute is emailStatus"
yet you try to fetch an entity emailStatus, where you likely want emails.
var request = NSFetchRequest(entityName: "emailStatus")
'typo'
fetch the right entity then: 'email'
var request = NSFetchRequest(entityName: "email")