问题
I mostly work with dictionaries since I am fairly new but here we have an embedded struct that I need to loop through. With this, I need to be able to populate expanding cells in UITableView.
My struct looks like this:
struct Complain: Codable {
let eMail, message, timeStamp, userEmail: String
let status: Bool
let planDetails: PlanDetails
enum CodingKeys: String, CodingKey {
case eMail = "E-mail"
case message = "Message"
case timeStamp = "Time_Stamp"
case userEmail = "User_Email"
case status, planDetails
}
}
// MARK: - PlanDetails
struct PlanDetails: Codable {
let menuItemName: String
let menuItemQuantity: Int
let menuItemPrice: Double
}
And my query looks like this:
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let error = error {
print("error:\(error.localizedDescription)")
} else {
for document in documentSnapshot!.documents {
let eMail = document.get("E-mail")
let message = document.get("Message")
let timeStamp = document.get("Time_Stamp")
let userEmail = document.get("User_Email")
let planDetails = document.get("planDetails")
// how to loop through planDetails
}
}
I have gotten this far:
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let documentSnapshot = documentSnapshot {
for document in documentSnapshot.documents {
guard let planDetails = document.get("planDetails") as? [[String : Any]] else {
let email = document.get("E-mail")
let message = document.get("Message")
let timeStamp = document.get("Time_Stamp")
let userEmail = document.get("User_Email")
let status = false
}
for plan in planDetails {
if let menuItemName = plan["menuItemName"] as? String {
// not sure I populate the menuItemsName, menuItemsQuantity and menuItemsPrice within the array
}
}
}
}
}
UPDATE 2:
Final query: This is finally working as expected. But am not able to populate the expanding cells.
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let documentSnapshot = documentSnapshot {
for document in documentSnapshot.documents {
guard let planDetails = document.get("planDetails") as? [[String : Any]],
let email = document.get("E-mail") as? String,
let message = document.get("Message") as? String,
let timeStamp = document.get("Time_Stamp") as? String,
let userEmail = document.get("User_Email") as? String,
let status = document.get("status") as? Bool else {
continue
}
for plan in planDetails {
guard let menuItemName = plan["menuItemName"] as? String,
let menuItemQuantity = plan["menuItemQuantity"] as? Int,
let menuItemPrice = plan["menuItemPrice"] as? Double else {
continue
}
let planDetails = PlanDetails(menuItemName: menuItemName, menuItemQuantity: menuItemQuantity, menuItemPrice: menuItemPrice)
let complaint = Complain(eMail: email, message: message, timeStamp: timeStamp, userEmail: userEmail, status: status, planDetails: planDetails)
self.messageArray.append(complaint)
print(self.messageArray)
}
}
}
}
回答1:
EDIT
// OPTION 1 - FULL REQUIREMENT
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let documentSnapshot = documentSnapshot {
for document in documentSnapshot.documents {
// all of these properties are required to parse a single document
guard let planDetails = document.get("planDetails") as? [[String : Any]],
let email = document.get("E-mail") as? String,
let message = document.get("Message") as? String,
let timeStamp = document.get("Time_Stamp") as? String,
let userEmail = document.get("User_Email") as? String,
let status = document.get("status") as? Bool else {
continue // continue this loop
}
for plan in planDetails {
// all of these properties are required to instantiate a struct
guard let name = plan["menuItemName"] as? String,
let price = plan["menuItemName"] as? Double,
let quantity = plan["menuItemQuantity"] as? Int else {
continue // continue this loop
}
let plan = PlanDetails(menuItemName: name, menuItemQuantity: quantity, menuItemPrice: price)
// then you will likely append this plan to an array
}
}
}
}
// OPTION 2 - PARTIAL REQUIREMENT
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let documentSnapshot = documentSnapshot {
for document in documentSnapshot.documents {
// all of these properties are required to parse a single document
guard let planDetails = document.get("planDetails") as? [[String : Any]],
let email = document.get("E-mail") as? String,
let message = document.get("Message") as? String else {
continue // continue this loop
}
// these properties are not required
let timeStamp = document.get("Time_Stamp") as? String // optional (can be nil)
let userEmail = document.get("User_Email") as? String // optional (can be nil)
let status = document.get("status") as? Bool ?? false // not optional because it has a default value of false
for plan in planDetails {
// all of these properties are required to instantiate a struct
guard let name = plan["menuItemName"] as? String,
let price = plan["menuItemName"] as? Double,
let quantity = plan["menuItemQuantity"] as? Int else {
continue // continue this loop
}
let plan = PlanDetails(menuItemName: name, menuItemQuantity: quantity, menuItemPrice: price)
// then you will likely append this plan to an array
}
}
}
}
There are a number of other ways you can do this, these are just a couple. For example, you can instantiate the struct with the [String: Any] dictionary itself.
回答2:
I finally figured out what the problem was. Had to do with the way I setup the struct and how I populate the array.
Right way is as such i.e. the planDetails need to be cast as an array:
struct Complain: Codable {
let eMail, message, timeStamp, userEmail: String
let status: Bool
let planDetails: [PlanDetails]
enum CodingKeys: String, CodingKey {
case eMail = "E-mail"
case message = "Message"
case timeStamp = "Time_Stamp"
case userEmail = "User_Email"
case status, planDetails
}
}
// MARK: - PlanDetails
struct PlanDetails: Codable {
let menuItemName: String
let menuItemQuantity: Int
let menuItemPrice: Double
}
And then I need to iterate through each plan item, add it to the array and then add the array to the top level Complain:
db.collection("Feedback_Message").getDocuments() { documentSnapshot, error in
if let documentSnapshot = documentSnapshot {
for document in documentSnapshot.documents {
guard let planDetails = document.get("planDetails") as? [[String : Any]],
let email = document.get("E-mail") as? String,
let status = document.get("status") as? Bool else {
continue
}
for plan in planDetails {
guard let menuItemName = plan["menuItemName"] as? String,
let menuItemQuantity = plan["menuItemQuantity"] as? Int else {
continue
}
let singlePlan = PlanDetails(menuItemName: menuItemName, menuItemQuantity: menuItemQuantity)
self.planDetailsArray.append(singlePlan)
}
let complain = Complain(eMail: email, status: status, planDetails: self.planDetailsArray)
self.planDetailsArray.removeAll()
self.messageArray.append(complain)
}
}
// Print the main array or load table
}
}
bsod's answer stays as the correct answer because without his help, I would not have been able to arrive at his conclusion.
来源：https://stackoverflow.com/questions/60955542/how-do-i-loop-through-a-firestore-document-that-has-an-array-of-maps