Retrieve firebase Image - ImageView - swift

Question

Hello everyone I am trying to take my image from the firebase database and present it into an image view as the profile image of the user. The first thing I do is create a method to retrieve the photo data in an array
class PhotoService {
static func retrievePhotos(completion: #escaping ([Photo]) -> Void) {
//get a databas refrence
let db = Firestore.firestore()
//get data from "photos" collection
db.collection("photos").getDocuments { (snapshot, Error) in
//check for errors
if Error != nil {
//error in retrieving photos
return
}
//get all the documents
let documents = snapshot?.documents
//check that documents arent nil
if let documents = documents {
//create an array to hold all of our photo structs
var photoArray = [Photo]()
//loop through documents, get a photos struct for each
for doc in documents {
//create photo struct
let p = Photo(snapshot: doc)
if p != nil {
//store it in an array
photoArray.insert(p!, at: 0)
}
}
//pass back the photo array
completion(photoArray)
}
}
}
Then I call that class and attempt to display the Image in the image view
#IBOutlet var profilePictureImageView: UIImageView!
var photos = [Photo]()
override func viewDidLoad() {
super.viewDidLoad()
//call the photo service to retrieve the photos
PhotoService.retrievePhotos { (retrievedPhotos) in
//set the photo array to the retrieved photos
self.photos = retrievedPhotos
//make the image view a circle
self.profilePictureImageView.layer.cornerRadius = self.profilePictureImageView.bounds.height / 2
self.profilePictureImageView.clipsToBounds = true
//make the image view display the photo
var photo:Photo?
func displayPhoto(photo:Photo) {
//check for errors
if photo.photourl == nil {
return
}
//download the image
let photourl = URL(string: photo.photourl!)
//check for erorrs
if photourl == nil {
return
}
//use url session to download the image asynchronously
let session = URLSession.shared
let dataTask = session.dataTask(with: photourl!) { (data, response, Error) in
//check for errors
if Error == nil && data != nil {
//let profilePictureImageView = UIImage()
let image = UIImage(data: data!)
//set the image view
DispatchQueue.main.async {
self.profilePictureImageView.image = image
}
}
}
dataTask.resume()
}
}
}
}
I dont understand what I am doing wrong and why the image is not showing up if anyone can explain this to me and give me an example with code that would be amazing, explain it as though you are explaining it to a kid in grade 5

Answer 1

A quick way to get Image from Firebase and assigning it to an ImageView can be done easily in these Steps.
Function to Get PhotoUrl
//Function to get photo of loggedin User
func getUrl(Completion:#escaping((String)->())) {
let userID = Auth.auth().currentuser?.uid
let db = Firestore.firestore().collection("photos").document(userID)
db.getDocument { (docSnapshot, error) in
if error != nil {
return
} else {
guard let snapshot = docSnapshot, snapshot.exists else {return}
guard let data = snapshot.data() else {return}
let imageUrl = data["photoUrl"] as! String
completion(imageUrl)
}
}
}
To download image and assign it to image view
//Call this function in VC where your `ImageView` is
func getImage(Url:String){
DispatchQueue.global().async {
let url = URL(string: Url)
if let data = try? Data(contentsOf: url!) {
DispatchQueue.main.async {
self.profilePictureImageView.image = UIImage(data: data)
}
}
}
}
}
Call these inside viewDidLoad like this:
getUrl{(url) in
getImage(Url:url)
}