Ambiguous use of 'subscript' and Cannot call value of non-function type 'AnyObject' errors retrieving data from Firebase in SWIFT 4.1 - ios

Question

I'm changing the way I'm posting and retrieving firebase CLLocationCoordinated2D, from one post per value to one post with all values, so I found this post and I would like to implement it in my own code. Retrieving data from Firebase and storing as annotations on a map .
Im having the errors mentioned in the title on the constants date, time, latitude, longitude and desc.
I'm still learning Firebase so any explanation will be very helpful. Tis is the function where I get the errors.
func displayAnnotations() {
let ref = Database.database().reference()
ref.child("Sightings").observe(.childAdded, with: { (snapshot) in
let date = (snapshot.value as AnyObject?)!("Date") as! String?
let time = (snapshot.value as AnyObject)!("Time") as! String?
let latitude = (snapshot.value as AnyObject)!("Latitude") as! String?
let longitude = (snapshot.value as AnyObject?)!("Longitude") as! String?
let desc = (snapshot.value as AnyObject?)!("Description") as! String?
let annotation = MKPointAnnotation()
annotation.coordinate = CLLocationCoordinate2D(latitude: (Double(latitude!))!, longitude: (Double(longitude!))!)
annotation.title = date
annotation.subtitle = time
self.mapView.addAnnotation(annotation)
})}
and this is the posting function:
func post() {
let date = dateLabel.text
let time = timeLabel.text
let latitude = latitudeLabel.text
let longitude = longitudeLabel.text
let sightingDescription = descriptionLabel.text
let post: [String:String] = ["Date" : date as AnyObject,
"Time" : time as AnyObject,
"Latitude" : latitude as AnyObject,
"Longitude" : longitude as AnyObject,
"Description" : sightingDescription as AnyObject]
var ref: DatabaseReference!
ref = Database.database().reference()
ref.child("Sightings").childByAutoId().setValue(post)
}
Is it just because it's written for a version previous to swift 4.1?

Answer 1

You changed [] to ()
let dic = snapshot.value as! [String:String]
let date = dic["Date"]
let time = dic["Time"]
let latitude = dic["Latitude"]
let longitude = dic["Longitude"]
let desc = dic["Description"]