Access values in multidimentional Swift array? - ios

I'd like to populate a tableView with results from a Firebase query. I successfully get the results and store them into an array but I'm struggling with how to put those values into the table.
I'm getting back a "userID" and a "title". I'm storing those in an array [[String]]. An example of an array after getting back a value would be [["OYa7U5skUfTqaGBeOOplRLMvvFp1", "manager"],["JQ44skOblqaGBe98ll5FvXzZad", "employee"]]
How would I access an individual value, such as the userID? This is what I have so far in my cellForRowAtIndexPath function:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
let invite = inviteArray[indexPath.row]
print(inviteArray)
print(invite)
return cell
}
Thanks!
EDIT: added function to store snapshot in an array
var dictArray: [Dictionary<String, String>] = []
func getAlerts(){
let invitesRef = self.rootRef.child("invites")
let query = invitesRef.queryOrderedByChild("invitee").queryEqualToValue(currentUser?.uid)
query.observeEventType(.Value, withBlock: { snapshot in
for child in snapshot.children {
guard let invitee = child.value["invitee"] as? String else{
return
}
guard let role = child.value["role"] as? String else{
return
}
self.dictArray.append(child as! Dictionary<String, String>)
print(self.dictArray)
}
})
}

Related

Changing a collectionView cell changes all of them

This is the code that gets the info from Firebase. It changes the cell's imageView image and the label's text. When it runs the code all of the cells have the same image and label text.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "suggestionCollectionViewCell", for: indexPath) as! SuggestionCollectionViewCell
Database.database().reference().child("users").observeSingleEvent(of: .childAdded) { (snapshot: DataSnapshot) in
if let dict = snapshot.value as? [String : Any] {
let imageURL = dict["imageURL"] as! String
let url = URL(string: imageURL)
let username = dict["username"] as! String
cell.imageView!.sd_setImage(with: url, completed: nil)
cell.usernameLabel.text = username
}
}
return cell
}
Actually for every cell rendering, you are fetching all the users from your Firebase database. Every call's last call is the user you are seeing multiple times. It overrides the previous ones.
To fix you problem you can store your users in an array.
var users = [User]()
To populate this array, you call a similar function like this in your viewDidLoad
func fetchUsers() {
Database.database().reference().child("users").observeSingleEvent(of: .childAdded) { (snapshot: DataSnapshot) in
if let dict = snapshot.value as? [String : Any] {
let user = User()
//set user properties here
users.append(user)
}
}
}
When you fetched all the users, you should reload your collectionView
collectionView.reloadData()
In your cellForItemAt function you can now access the users
let user = users[indexPath.row]
Use the user variable to setup you cell
To remove this problem, firstly you should gather all the data from the firebase in array and then use that array for table view accordingly.

Index out of range for only last 2 values?

I am currently getting index out of range but this only happens after the first 3 items have been displayed successfully. I looked through the code and I still don't know where im going wrong. Index out of range happens only when trying to load text in the cells.
Log when method is called from viewdidload:
Description of indexPath: 0
Description of indexPath: 1
Description of indexPath: 2
Log when I press a button to load the rest of images:
Description of indexPath: 0
Description of indexPath: 1
Description of indexPath: 2
Description of indexPath: 3
Datasource method where indexpath is out of range:
//MARK: - tableview datasource methods
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
if arrayOfImgObj.count > 0 {
cell.imageView?.image = arrayOfImgObj[indexPath.row].imageTempt
print("Description of indexPath: ",indexPath.row)
cell.textLabel?.text = arrayOfUIDs[indexPath.row] // index out of range
} else {
print("\(arrayOfImgObj.count) not over 0 yet")
}
return cell
}
Method that is called when viewDidload:
//testing array
var arrayOfUIDs = User().users
func fetchAllUserFristImage() {
Database.database().reference().child("Posts").observe(.childAdded, with: {(snapshot) in
if (snapshot.value as? [String: AnyObject]) != nil {
let user = User()
user.id = snapshot.key
//testing array
self.arrayOfUIDs.append(snapshot.key)
print("\(String(describing: user.id)) <-- SHUD BE THE USERUID")
self.databaseRef = Database.database().reference()
let usersPostRef2 = self.databaseRef.child("Posts").child(user.id!)
usersPostRef2.observe(.value, with: {(postXSnapshots) in
if let postDictionary2 = postXSnapshots.value as? NSDictionary {
for (p) in postDictionary2 {
let posts = p.value as! NSDictionary
//to get back to where i was delete the below for i
for (i) in posts {
let imageUrlString = i.value as! NSDictionary
guard let postUrl = imageUrlString.value(forKey: "image1") else {return}
//below is ting from below
if postUrl != nil {
self.feedArray.append(Post(fetchedImageURL: postUrl as! String))
let imageUrlString = "\(postUrl)"
let imageUrl = URL(string: imageUrlString)!
print("\(imageUrl) this shud be img url's of posts")
let imageDataL = try! Data(contentsOf: imageUrl)
self.imageObject.img2 = UIImage(data: imageDataL)
let image1ToDisplay: UIImage = self.imageObject.img2!
self.arrayOfImgObj.append(forTable(imageTempt: image1ToDisplay))
} else {print("this user had no posts, was nil")}
}
}
}
})
}
//below shud stay same
DispatchQueue.main.async {
self.tableView.reloadData()
}
})
}
Edit:
I have changed teh code to only use one array of objects:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
if arrayOfImgObj.count > 0 {
cell.imageView?.image = arrayOfImgObj[indexPath.row].imageTempt
print("Description of indexPath: ",indexPath.row)
cell.textLabel?.text = arrayOfImgObj[indexPath.row].users[indexPath.row] // index out of range
} else {
print("\(arrayOfImgObj.count) not over 0 yet")
}
return cell
}
changing one line in the function to this:
self.arrayOfImgObj.append(forTable(imageTempt: image1ToDisplay, users: snapshot.key))
Thanks in advance!
Your problem is that you have two arrays:
arrayOfUIDs which has one entry for each user
arrayOfImgObj which has 0-n entries for each user (So, it is likely that the number of objects in this array will be greater than the number of objects in arrayOfUIDs.
You are basing your row count on the arrayOfImgObj, but then using the row number to index into arrayOfUIDs, which results in an array bounds exception.
It may well be more elegant to have table view section per userid, but if you want to put all of the rows in a single section I would suggest you use a single array of structs as your data model.
Use something like:
struct UserImage {
var userID: String
var image: UIImage
}
var tableData = [UserImage]()
Then as you fetch each image, create a new struct and put it in your array:
func fetchAllUserFristImage() {
Database.database().reference().child("Posts").observe(.childAdded, with: {(snapshot) in
if snapshot.value as? [String: AnyObject] != nil {
let user = snapshot.key
self.databaseRef = Database.database().reference()
let usersPostRef2 = self.databaseRef.child("Posts").child(user)
usersPostRef2.observe(.value, with: {(postXSnapshots) in
if let postDictionary2 = postXSnapshots.value as? [String:AnyObject] {
for (p) in postDictionary2 {
if let posts = p.value as? [String:AnyObject] {
//to get back to where i was delete the below for i
for (i) in posts {
if let imageUrlString = i.value as? [String:AnyObject], let postUrl = imageUrlString.["image1"] as? String {
self.feedArray.append(Post(fetchedImageURL: postUrl))
if let imageUrl = URL(string: postUrl), let imageDataL = try? Data(contentsOf: imageUrl), let image = UIImage(data: imageDataL) {
self.tableData.append(UserImage(userID: user, image: image))
} else {print("this user had no posts, was nil")}
}
}
}
}
}
})
//below shud stay same
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
}
Now, your cellForRow can be:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell.imageView?.image = tableData[indexPath.row].image
cell.textLabel?.text = tableData[indexPath.row].userID
return cell
}

swift table view cells does not let me use indexPath.row

i am trying to populate data into cells inside of a table view. I created a chosenPlanData var which is initialized to an object with the data inside of it.. The object has properties such as "name" and "event location". An issue occurs when inside of 'cellForRowAt'. It does not let me add [indexPath.row] to the cell i am creating, which in turn does not populate the cells correctly.
For instance - i removed indexPath.row from the first cell.nameLbl.text call - and in turn every single name label in the table view was the same. here is piece of the code
var chosenPlanData = ChosenPlan()
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell = tableView.dequeueReusableCell(withIdentifier: "individualPlansCell") as? PlanitsHomeViewCell else { return UITableViewCell() }
cell.nameLbl.text = chosenPlanData.nameOfEvent[indexPath.row] // error Cannot assign value of type 'Character' to type 'String?'
cell.dateAndTimeLbl.text = chosenPlanData.eventStartsAt[indexPath.row] as? String // error 'subscript' is unavailable: cannot subscript String with an Int, see the documentation comment for discussion
cell.nameLbl.text = chosenPlanData.nameOfEvent // This works - but every single cell has the same nameLbl though
return cell
}
// Here is the call back where i initialize the value for chosenPlanData
let EventbriteTVC = segue.destination as! EventbriteTableView
EventbriteTVC.callbackChosePlan = { result in
DispatchQueue.main.async {
self.individualPlanitsTableView.reloadData()
}
self.chosenPlanData = result
}
import Foundation
import UIKit
class ChosenPlan {
var nameOfEvent : String = ""
var eventStartsAt : String = ""
var eventLocationIs : String = ""
var eventURL : String = ""
var imageForPlan : String?
convenience init( eventName: String, eventTime: String, eventLocation: String, eventImage: String){
self.init()
self.nameOfEvent = eventName
self.eventStartsAt = eventTime
self.eventLocationIs = eventLocation
//self.eventURL = eventLink
self.imageForPlan = eventImage
//eventLink: String,
}
}
Your chosenPlanData variable is a single instance of ChosenPlan - You cannot subscript a single instance.
It needs to be an array of ChosenPlan:
var chosenPlanData = [ChosenPlan]()
Then you can index into this array:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell = tableView.dequeueReusableCell(withIdentifier: "individualPlansCell") as? PlanitsHomeViewCell else { return UITableViewCell() }
cell.nameLbl.text = chosenPlanData[indexPath.row].nameOfEvent
cell.dateAndTimeLbl.text = chosenPlanData[indexPath.row].eventStartsAt
extending my comment
var chosenPlanData = ChosenPlan()
chosenPlanData is object of ChosenPlan
Now in cellForRow you writing chosenPlanData.nameOfEvent[indexPath.row] but nameOfEvent is String as per your ChosenPlan that you mentioned in question.
For more info,
chosenPlanData.nameOfEvent[indexPath.row] this line represents you using the n th (indexPath.row) object of nameOfEvent which is object of chosenPlanData
Hope now will be more cleared.
Solution
var chosenPlanData = [ChosenPlan]() <- create array
In cellForRow chosenPlanData[indexPath.row].nameOfEvent that means you'r using nameOfEvent of nth object of chosenPlanData.
Type handling is very important in Swift. Try this.
cell.nameLbl.text = String(chosenPlanData.nameOfEvent[indexPath.row])
let index = chosenPlanData.eventStartsAt.index(chosenPlanData.eventStartsAt.startIndex, offsetBy: 3)
cell.dateAndTimeLbl.text = String(chosenPlanData.eventStartsAt[index])
if
var chosenPlanData = [ChosenPlan]()
Try this:-
cell.nameLbl.text = "\(chosenPlanData[indexPath.row].nameOfEvent)"
or
cell.nameLbl.text = "\(chosenPlanData[indexPath.row].nameOfEvent ?? "")"

How to retrieve UserDefaults because cells are empty

I made a struct dictionary to get the user title and URL, and then I store them on the phone but when I come to retrieve the data in cellForRow method the cell label is empty, what should appear is the title.(tableView starts off empty until user starts to populate it with the AddArticle action)
So my question is if I'm doing it right because the cell label just turns out nil?
Struct Dictionary:
struct AddMagazine {
let rssUrl: String
let title: String
init(dict: [String : String]){
title = dict["title"] ?? ""
rssUrl = dict["rssUrl"] ?? ""
}
}
var userMagazineTitle = [AddMagazine]()
Getting values from textField:
#IBAction func AddArticle(_ sender: Any) {
animateIn()
tableView.isScrollEnabled = false
}
func addArticleTitle() {
let UserMagazines = AddMagazine.init(dict: ["title": RssTitle.text!, "rssUrl": RssText.text!])
let storedRssUrl = UserMagazines.rssUrl
self.dataString = storedRssUrl
//setting
defaults.set(dataString, forKey: "storedArray")
userMagazineTitle.append(UserMagazines)
tableView.reloadData()
}
Trying to retrieve title here:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "myCell", for: indexPath) as! MyFeedTableViewCell
let headlineName = defaults.object(forKey: "storedArray") as? AddMagazine
cell.myHeadline.text = headlineName?.title
cell.indentationLevel = 3
return cell
}
You’re storing a String object in defaults for “storedArray” but then you typecast it to an AddMagazine when you read it from defaults. Change what you store or read it as a string.
I agree with #Joakim Danielson. You are storing storedRssUrl which is a string into userdefaults and while retrieving you are type casting as AddMagazine hence it will be nil.
self.dataString = storedRssUrl
//setting
defaults.set(dataString, forKey: "storedArray") --> Here you are storing string
let headlineName = defaults.object(forKey: "storedArray") as? AddMagazine --> Here you are fetching as AddMagazine.
//It should be like this
let headlineName = defaults.object(forKey: "storedArray") as? String

Index of JSON Array Swift

I am using this library to parse an API endpoint that returns an array: https://github.com/SwiftyJSON/SwiftyJSON
I am grabbing an array fetched from a JSON response and I am trying to feed it into a table.
Right after my class in my view controller is declared, I have
var fetched_data:JSON = []
Inside of my viewDidLoad method:
let endpoint = NSURL(string: "http://example.com/api")
let data = NSData(contentsOfURL: endpoint!)
let json = JSON(data: data!)
fetched_data = json["posts"].arrayValue
To feed the table, I have:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell: UITableViewCell = self.tableView.dequeueReusableCellWithIdentifier("cell1")! as UITableViewCell
cell.textLabel?.text = self.fetched_data[indexPath.row]
return cell
}
I am getting this error, when trying to set the cell textLabel:
Cannot subscript a value of a type ‘JSON’ with an index type of ‘Int’
How do I do this properly and get this to work?
You are declaring fetched_data as JSON
var fetched_data:JSON = []
but you are assigning Array to it:
fetched_data = json["posts"].arrayValue
Lets change the type to array of AnyObject:
var fetched_data: Array<AnyObject> = []
and then assigning should be like this (we have [AnyObject] so we need to cast):
if let text = self.fetched_data[indexPath.row] as? String {
cell.textLabel?.text = text
}
Edit: You also need to remember to assign correct Array, by doing arrayObject instead of arrayValue:
fetched_data = json["posts"].arrayObject

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