Firebase retrieves my Double as a String in Swift iOS? - ios

Question

So I'm saving a dictionary to my firebase. The dictionary is located in a custom class I made called FoodItem. Here's the lines where I save the dictionary:
let favRef = self.ref.childByAppendingPath("urlhidden")
favRef.setValue(foodItem.toAnyObject())
foodItem is a FoodItem object, here's the part of my FoodItem class that implements .toAnyObject()
var key: String
var ref: Firebase?
var name: String
var description: String
var minCal: Int
var maxCal: Int
var containsNuts: Bool
var vegetarian: Bool
var price: Double //**NOTE THAT PRICE IS A DOUBLE**
func toAnyObject()->[String:AnyObject]{
return ["name":self.name,
"price":self.price,
"description":self.description,
"minCal":self.minCal,
"maxCal":self.maxCal,
"containsNuts":self.containsNuts,
"vegetarian":self.vegetarian]
}
So those bits of code combined saves my data to my firebase. Works as it should. But when I retrieve the data, my price variable is a string? I'll explain...
Here's where I retrieve the data:
func getCurrentOrder(){
let uid = ref.authData.uid
ref = Firebase(url: "urlhidden")
ref.observeEventType(.Value, withBlock: { snapshot in
var newItems = [FoodItem]()
for item in snapshot.children {
let foodItem = FoodItem(snapshot: item as! FDataSnapshot)
newItems.append(foodItem)
}
self.order = newItems
self.tableView.reloadData()
})
}
That FoodItem constructor you see with the snapshot takes the data from my firebase and assigns my FoodItem variables to those values in my firebase. Here's that code:
init(snapshot: FDataSnapshot) {
key = snapshot.key
name = snapshot.value["name"] as! String
price = snapshot.value["price"] as! Double //**NOTE STILL A DOUBLE**
description = snapshot.value["description"] as! String
minCal = snapshot.value["minCal"] as! Int
maxCal = snapshot.value["maxCal"] as! Int
containsNuts = snapshot.value["containsNuts"] as! Bool
vegetarian = snapshot.value["vegetarian"] as! Bool
ref = snapshot.ref
}
However when I run my code, I see that it prints the double as a String
As you can see, there are clearly quotes around the Double variable "price".
And I get this error:
Could not cast value of type '__NSCFString' (0xff0ee0) to 'NSNumber' (0x13ff81c).
With this line of code highlighted in red:
price = snapshot.value["price"] as! Double
Which is located inside the FoodItem constructor with the snapshot as I posted above.
Any Ideas???
*EDIT: It does the same thing for my int variables. Same error message

Answer 1

It never actually saved it as a String. I believe I had that value in there as some old code in which I did save it as a String. I deleted my entries in the database and tried it again and it works just fine. Thank you to those who attempted to answer my question.

Answer 2

2017 example
It may save someone some typing, here's some completely typical code to observe a simple number value. Let's say it's a fraction called SomeFraction.
As always, Firebase rocks :)
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
dev_listenForLiveFraction()
}
var r1: DatabaseReference? = nil
func dev_listenForLiveFraction() {
let p1 = "something/someFractionForExample"
r1 = Database.database().reference(withPath: p1)
r1!.observe(.value) { (snapshot) in
let sf: NSNumber = snapshot.value as? NSNumber ?? 0.666
self.example_handleSomeFraction(sf)
}
}
func example_handleSomeFraction(_ sf: NSNumber) {
print("the fraction is now \(sf)")
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
clearObservations()
}
private func clearObservations() {
if r1 != nil {
r1?.removeAllObservers()
r1 = nil
}
}