How to merge values with similar keys for NSdictionary - swift

Question

Hello i have situation where i have getting a raw response for the server like this
(
{
"Nov 2018" = {
AudioFileURL = "https://www.GeorgeA.m4a";
AudioFileText = "GeorgeA";
};
},
{
"Nov 2018" = {
AudioFileURL = "https://www.GeorgeB.m4a";
AudioFileText = "Georgeb";
};
},
{
"Nov 2018" = {
AudioFileURL = "https://www.Georgec.m4a";
AudioFileText = "Georgec";
};
},
{
"Sep 2018" = {
AudioFileURL = "https://www.GeorgeB.m4a";
AudioFileText = "GeorgeD";
};
}
)
now i would like to combine all the Values with the same key so that i can use them in section with UITableView controller . can someone please provide me some guidance for that .
The output i am looking for is something like this
(
{
"Nov 2018" = {
[AudioFileURL = "https://www.GeorgeA.m4a";
AudioFileText = "GeorgeA"],
[AudioFileURL = "https://www.GeorgeB.m4a";
AudioFileText = "GeorgeB"],
[AudioFileURL = "https://www.GeorgeC.m4a";
AudioFileText = "GeorgeC"];
};
},
{
"Sep 2018" = {
[AudioFileURL = "https://www.GeorgeB.m4a";
AudioFileText = "GeorgeD";]
};
}
)

Answer 1

First make a struct(s) that represents the info you want in one cell:
struct AudioFileInfo {
let urlString: String
let text: String
init(dict: [String: String]) {
urlString = dict["AudioFileURL"] ?? ""
text = dict["AudioFileText"] ?? ""
}
}
struct CellInfo {
let date: String
let audioFileInfos: [AudioFileInfo]
}
Then you can:
let cellInfos = response
.flatMap {
$0.map { ($0.key, AudioFileInfo(dict: $0.value)) }
}
.reduce([CellInfo]()) { partial, item in
var new = partial
if let index = partial.index(where: { $0.date == item.0 }) {
new[index] = CellInfo(date: partial[index].date, audioFileInfos: partial[index].audioFileInfos + [item.1])
}
else {
new.append(CellInfo(date: item.0, audioFileInfos: [item.1]))
}
return new
}
This will give you an array of CellInfo objects.
As a general rule, this how you solve this sort of problem. First define a type that represents the output you want, then manipulate the input until you create objects of that type. Playground is your friend for this sort of thing.

Answer 2

Something like this will work for you
typealias AudioFile = (url: String, text: String)
class DictArray {
var items: [MainModal]
class MainModal {
let date: String
var files: [AudioFile]
init(key: String, file: AudioFile) {
self.key = key
self.files = [file]
}
}
init(dictArray: [[String: [String: String]]]) {
for dict in dictArray {
if let date = dict.keys.first {
if let item = items.first(where: { $0.date == date }) {
guard let value = dict.values.first as? [String: String] else { continue }
let file = AudioFile(url: value["AudioFileURL"]!, text: value["AudioFileText"]!)
item.files.append(file)
} else {
guard let value = dict.values.first as? [String: String] else { continue }
let file = AudioFile(url: value["AudioFileURL"]!, text: value["AudioFileText"]!)
items.append(MainModal(key: date, files: [file]))
}
}
}
}
}
DictArray(dict: json)