Swift loop through array of dictionaries - loops

Question

Why am I getting this error when looping through an array of dictionaries ?
import UIKit
let tableView = UITableView()
func meh() {
let product = buildCells()
for (identifier, nib) in product {
tableView.registerNib(nib, forCellReuseIdentifier: identifier)
}
}
func buildCells() -> [[String: UINib]] {
var collector = [[String: UINib]]()
let identifier = "identifier"
let nib = UINib(nibName: "TableViewCell", bundle: nil)
let asdf = [identifier: nib];
collector.append(asdf)
return collector
}
The forin loop in the meh() method produces the following error:
'Dictionary' is not convertible to '([[String : UINib]], [[String : UINib]])'

Answer 1

We can't iterate through the keys and values of an array of dictionaries. We can iterate through the dictionaries though. And for each dictionary, we can iterate through its keys and values:
let product = buildCells()
for dict in product {
for (identifier, nib) in dict {
tableview.registerNib(nib, forCellReuseIdentifier: identifier)
}
}
But I think the problem is actually more likely the nonsense going on in buildCells(). Why are you returning an array of dictionaries? Do you plan to have duplicate keys? I don't think the tableview will let you register multiple nibs for the same identifier.
Why don't we just return a dictionary?
func buildCells() -> [String: UINib] {
var dict = [String: UINib]()
dict["identifier"] = UINib(nibName: "TableViewCell", bundle: nil)
// rinse & repeat for all of your other ID/nib combos with no duplicate IDs
return dict
}
Now we can iterate over the key/value pairs in the dictionary without the outer loop:
for (identifier, nib) in dict {
tableview.registerNib(nib, forCellReuseIdentifier: identifier)
}