Trying to add objects to Class and save info to Firebase database - swift

Question

I want to save new objects via a view controller in my app. However, I want these new objects to load when the app is logged into. I am using firebase to save data into a database, but how can I save an object and have it return when the app is logged into again? I am new-ish to programming, sorry for any potential confusion.
Here is where the goal information is read when the app has been logged into.
for i in 0 ... clientList.count - 1 {
screenHandle = ref?.child(organizationCode).child(clientList[i].name).observe(.value, with: { (snapshot) in
let clientStuffLoad = snapshot.value as! [String:Any]
if clientStuffLoad["Goal 1 Description"] != nil {
clientList[i].goal1 = clientStuffLoad["Goal 1"] as! String
} else {
clientList[i].goal1 = ""
}
This is essentially what I have regarding adding a new member to the class Client:
#IBAction func addingClientSaveButton(_ sender: Any) {
var client7 = Client(name: addingClientName.text!,
goal1: addingClientGoal1.text!, goal2:
addingClientGoal2.text!,
goal3: addingClientGoal3.text!,
isSelected: false, s: 1,
ind: 1, targetBehavior1 : addingClientTB1.text!,
targetBehavior2 : addingClientTB2.text!,
targetBehavior3 : addingClientTB3.text!,
targetBehavior1Info : addingClientTB1Info.text!,
targetBehavior2Info : addingClientTB2Info.text!,
targetBehavior3Info : addingClientTB3Info.text!)
but I would like the object name to read the client name input as opposed to client7
The second part to this is that I want a way to write this to the database, and be able to read it at log in so that I can use the properties of the class and add to it when adding a new client.

Answer 1

This is a super broad question because it covers a lot of different aspects of working with Firebase; writing, reading, handling DataSnapshots etc. Also, I don't know what your data represents so I picked something for me to cover some of the aspects of working with Firebase.
There's no error checking but it works as is. I've commented along the way.
Firebase has no objects; just parent and child nodes. Everything can be thought of as key: value pairs like a dictionary. You cannot write an object or read an object. Only NSString, NSNumber, NSDictionary and the dreaded NSArray (or their Swift counterparts)
Let's start with a class - there's 100 ways to do this but I like classes to be responsible for their properties as well as accepting them and presenting them
class WineClass {
var wine_key = ""
var name = ""
var varietal = ""
//this is used when creating a new wine object before storing in firebase
init(withName: String, andVarietal: String) {
self.name = withName
self.varietal = andVarietal
}
//this is used when we are loading data from firebase to create the wineclass object
init(withSnapshot: DataSnapshot) {
let wineName = withSnapshot.childSnapshot(forPath: "wine_name").value as? String ?? "No Wine Name"
let wineDict = withSnapshot.value as! [String: Any]
let wineVarietal = wineDict["wine_varietal"] as? String ?? "No Wine Varietal"
self.wine_key = withSnapshot.key //when we read a wine, this will be it's reference in case we want to update or delete it
self.name = wineName
self.varietal = wineVarietal
}
//this is use to create a dictionary of key:value pairs to be written to firebase
func getWineDictForFirebase() -> [String: Any] {
let d = [
"wine_name": self.name,
"wine_varietal": self.varietal
]
return d
}
}
Then, we need a class var to store the WineClass's. This would be for example a dataSource for a tableView
var wineArray = [WineClass]() //a class var array to store my wines
Then I will give you two buttons, one that populates and writes some wine to Firebase and then a second that read them in and prints to console
func button0() {
self.writeWine(withName: "Scarecrow", andVarietal: "Red Blend")
self.writeWine(withName: "Ghost Horse", andVarietal: "Cabernet Sauvignon")
self.writeWine(withName: "Screaming Eagle", andVarietal: "Cabernet Sauvignon, Merlot, Cabernet Franc")
}
func button1() {
self.readWines()
}
And then the function that accepts some strings as properites for each wine and writes them to Firebase
func writeWine(withName: String, andVarietal: String) {
let newWine = WineClass(withName: withName, andVarietal: andVarietal) //create a new wine object
let wineListRef = self.ref.child("wine_list") //get a reference to my firebase wine_list
let thisWineRef = wineListRef.childByAutoId() //a new node for this wine
let d = newWine.getWineDictForFirebase() //get the wine properties as a dictionary
thisWineRef.setValue(d) //save it in firebase
}
and finally a function that reads in those wines, and prints their properties in console
func readWines() {
let wineRef = self.ref.child("wine_list")
wineRef.observeSingleEvent(of: .value, with: { snapshot in //we are reading in the entire wine node which will contain many child nodes
let allWines = snapshot.children.allObjects as! [DataSnapshot] //cast each child node as a DataSnapshot & store in array
for wineSnap in allWines { //iterate over each child node in the array
let wine = WineClass(withSnapshot: wineSnap) //create a new wine, ensuring we also keep track of it's key
self.wineArray.append(wine) //add to the array
}
for wine in self.wineArray {
print(wine.wine_key, wine.name, wine.varietal)
}
})
}
lastly, when button0 is clicked, our Firebase looks like this
wine_list
-LhbjhkEC8o9TUISCjdw
wine_name: "Scarecrow"
wine_varietal: "Red Blend"
-LhbjhkEC8o9TUISCjdx
wine_name: "Ghost Horse"
wine_varietal: "Cabernet Sauvignon"
-LhbjhkEC8o9TUISCjdy
wine_name: "Screaming Eagle"
wine_varietal: "Cabernet Sauvignon, Merlot, Cabernet Franc"
and then the output when button1 is clicked
-LhbjhkEC8o9TUISCjdw Scarecrow Red Blend
-LhbjhkEC8o9TUISCjdx Ghost Horse Cabernet Sauvignon
-LhbjhkEC8o9TUISCjdy Screaming Eagle Cabernet Sauvignon, Merlot, Cabernet Franc
Note that self.ref is a reference to the root node of my firebase yours will need to reference your firebase.