Swift 2 - Create a array of arrays - arrays

Question

Im trying to make an array with multiple arrays inside of it.
Im using CloudKit to get the data.
import UIKit
import CloudKit
var questionsCount = 0
var questionsArray = [String]()
class hvadvilduhelstViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
//firstfield.setTitle("Klik her for at starte!", forState: .Normal)
//secondfield.setTitle("Klik her for at starte!", forState: .Normal)
firstfield.titleLabel?.lineBreakMode = NSLineBreakMode.ByWordWrapping
firstfield.titleLabel?.textAlignment = NSTextAlignment.Center
secondfield.titleLabel?.lineBreakMode = NSLineBreakMode.ByWordWrapping
secondfield.titleLabel?.textAlignment = NSTextAlignment.Center
let container = CKContainer.defaultContainer()
let publicData = container.publicCloudDatabase
let query = CKQuery(recordType: "Questions", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
publicData.performQuery(query, inZoneWithID: nil) { results, error in
if error == nil { // There is no error
for entry in results! {
let firstOne = [entry["Question1"] as! String]
let secondOne = firstOne + [entry["Question2"] as! String]
let thirdOne = secondOne + [String(entry["Question1Rating"] as! Int)]
let fourthOne = thirdOne + [String(entry["Question2Rating"] as! Int)]
let fithOne = fourthOne + [String(entry["Reports"] as! Int)]
questionsArray = questionsArray + fithOne
print(questionsArray)
}
}
else {
print(error)
}
}
}
Using previous code I am getting this in the console output:
["Dette er en test1", "Dette er en test2", "0", "0", "0", "test2", "test2", "0", "0", "0"]
instead of this (which is the output i want):
[["Dette er en test1", "Dette er en test2", "0", "0", "0"], ["test2", "test2", "0", "0", "0"]]
I simple can't figure out how to do this. My plan was to get a lot of records and put them inside of this single, huge array (to make it easy to use the 'value') Is there an easier/better way to do this?
Sorry for my english, not my native language.
Thanks for your help!

Answer 1

When you have a problem like this, make a Playground and experiment and do a little thinking. Here is what you are doing, in essence:
var arr = [String]()
for _ in (1...3) {
let first = ["Mannie"]
let second = first + ["Moe"]
let third = second + ["Jack"]
arr = arr + third
}
arr // ["Mannie", "Moe", "Jack", "Mannie", "Moe", "Jack", "Mannie", "Moe", "Jack"]
That isn't what you want, so don't do that. First, as your question title says, you want an array of arrays. Well then, you don't want to end up with a [String]; you just told us that you want a [[String]] (an array of arrays of strings)! So first make that change:
var arr = [[String]]()
Now, when you build your array and insert it into your array of arrays, use the append method (instead of the + operator):
arr.append(third)
Here's the result:
var arr = [[String]]()
for _ in (1...3) {
let first = ["Mannie"]
let second = first + ["Moe"]
let third = second + ["Jack"]
arr.append(third)
}
arr // [["Mannie", "Moe", "Jack"], ["Mannie", "Moe", "Jack"], ["Mannie", "Moe", "Jack"]]
Now go ye and do likewise in your real code.

Answer 2

Try this instead:
import UIKit
import CloudKit
var questionsCount = 0
var questionsArray = [[String]]()
class hvadvilduhelstViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
//firstfield.setTitle("Klik her for at starte!", forState: .Normal)
//secondfield.setTitle("Klik her for at starte!", forState: .Normal)
firstfield.titleLabel?.lineBreakMode = NSLineBreakMode.ByWordWrapping
firstfield.titleLabel?.textAlignment = NSTextAlignment.Center
secondfield.titleLabel?.lineBreakMode = NSLineBreakMode.ByWordWrapping
secondfield.titleLabel?.textAlignment = NSTextAlignment.Center
let container = CKContainer.defaultContainer()
let publicData = container.publicCloudDatabase
let query = CKQuery(recordType: "Questions", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
publicData.performQuery(query, inZoneWithID: nil) { results, error in
if error == nil { // There is no error
for entry in results! {
let firstOne = entry["Question1"] as! String
let secondOne = entry["Question2"] as! String
let thirdOne = String(entry["Question1Rating"] as! Int)
let fourthOne = String(entry["Question2Rating"] as! Int)
let fifthOne = String(entry["Reports"] as! Int)
questionsArray.append([firstOne, secondOne, thirdOne, fourthOne, fifthOne])
print(questionsArray)
}
}
else {
print(error)
}
}
}
}
Notably, questionsArray is now of type [[String]], not just [String], and for each entry, you want to append a new [String]