Retrieve JSON Object and populate array Swift - ios

I have a json object of this structure:
[
{
"id": 1,
"seat_no": 6
},
{
"id": 2,
"seat_no": 27
}
]
The main challenge is that I need to get the seat_no and add that to an int array which I will be using later on:
func getReserved() -> [Int] {
var reservedSeatsJSON : JSON = JSON()
var seats = Int()
var reservedSeats = [Int]()
for item in reservedSeatsJSON.array! {
seats = item["seat_no"].int!
reservedSeats.append(seats)
self.reservedSeatsLabel.text = "Reserved(\(reservedSeatsJSON.array!.count))"
}
return reservedSeats
}
Each time I run this, the reservedSeats returns empty. The main idea here is that I need to populate an int array in a for loop and return the populated array outside the for loop

First check is reservedSeatsJSON json contains actual JSON?
if it contains actual JSON then do as like below. short and simple way.
func getReserved() -> [Int] {
var reservedSeatsJSON : JSON = JSON()
self.reservedSeatsLabel.text = "Reserved(\(reservedSeatsJSON.array.count))"
return reservedSeatsJSON.arrayValue.map { $0["seat_no"].intValue }
}

Related

How to get one value from a Codable struct with multiple values?

I have a large JSON response and inside
{
"availabilityResultList": [
{
"availabilityRouteList": [
{
"availabilityByDateList": [
{
"originDestinationOptionList": [
there are 3 separate
"originDestinationOptionList": [
{
"fareComponentGroupList":[...]
},
{
"fareComponentGroupList":[...]
},
{
"fareComponentGroupList":[...]
},
],
I can access the values in the first 'fareComponentGroupList' with Codables
as
root.availabilityResultList.first?.availabilityRouteList.first?.availabilityByDateList.first?.originDestinationOptionList.first?.fareComponentGroupList.first?.xxx
How do I access values the second and third fareComponentGroupList ?
(I am sorry about these silly questions but I am new with swift Codables)
Since originDestinationOptionList returns an array of dictionary, just fetch it from there by index.
let originDestinationOptionList = root.availabilityResultList.first?.availabilityRouteList.first?.availabilityByDateList.first?.originDestinationOptionList
let firstobject = originDestinationOptionList[0]["fareComponentGroupList"]
let secondObject = originDestinationOptionList[1]["fareComponentGroupList"]
let firstObjectsFirstItem = firstObject[0]
If the above gives error, this works ( Swift 5)
let originDestinationOptionList = root.availabilityResultList.first?.availabilityRouteList.first?.availabilityByDateList.first?.originDestinationOptionList
let firstobject = originDestinationOptionList[0].fareComponentGroupList.first
let firstObjectsFirstItem = firstObject?. (add the remaining part)

swift parse json as per maintaining order

Suppose i have json string in which there is a json array called data.
The array holds json object of user profile data for example name,age,gender etc.
Now want to parse that json object as per order, for example if the object is
{
"name": "sample name",
"age": "30",
"gender": "male"
}
i want to parse the list as ordered like name,age,gender but with ios,when i convert the json object as dictionary , the order is changed,i know dictionary is not ordered so what is the the alternative to achieve this?
its a third party api so i dont have any hand on it,we have done it in android with linked hash map,but really stuck in swift , the last thing i would want to do is parse with regular expression.
im parsing the json in following way :
var rootData = try JSONSerialization.jsonObject(with: data!) as! [String:Any]
if let val = fromList["data"] {
let dataNode = val as! [[String:Any]]
for row in dataNode {
for (key,keyVal) in row {
//here the key is not in order.because when we cast it as dictionary the order gets changed.
}
}
For android we have achieved to do this with following function :
public ArrayList<LinkedHashMap<String, Object>> parseJsonArrayList(String odata, String arrayName) {
ArrayList<LinkedHashMap<String, Object>> mylist = new ArrayList<>();
try {
JSONObject e = new JSONObject(odata);
JSONArray data = e.getJSONArray(arrayName);
for(int i = 0; i < data.length(); ++i) {
JSONObject v = data.getJSONObject(i);
LinkedHashMap<String, Object> map = new LinkedHashMap<>(100, 0.75f, false);
Iterator keys = v.keys();
while(keys.hasNext()) {
String key = String.valueOf(keys.next());
//gph.log("debug4", key);
map.put(key, v.getString(key));
//gph.log("debug4", v.getString(key));
}
mylist.add(map);
}
} catch (JSONException var10) {
var10.printStackTrace();
}
return mylist;
}
Don’t try to order the dictionary. Instead create an array of the keys in the order you desire:
let keys = [“name”, “age”, “gender”]
Then access the dictionary with them:
for key in keys {
let value = dict[key]
// Present the value.
}
That will ensure the order you expect.
As you mentioned you cannot get the ordered data in Dictionary. If possible you can add the "order" key in your JSON like
[
{
"name": "sample name",
"order": 1
},
{
"age": "30",
"order": 1
},
{
"gender": "",
"male": "",
"order": 1
}
]
so that based on the order key you can do the sorting.

Filtering Arrays Containing Multiple Data Types in Swift3

I have an array like:-
var arrayData : Array<Dictionary<String, [BottleModel]>> = []
Bottle model :-
class BottleModel: NSObject {
var name : String
var price : Int
var reviews : Int
var category : String
var quantity : String
var id : String
var shopData : ShopModel
}
I want filtered array where price is > 2000
I tried let searchByInts = arrayData.filter({m in m.price < 200})
but getting below error:
Contextual closure
type '(Dictionary) -> Bool' expects 1 argument,
but 0 were used in closure body
How to filter such kind of array based on price
Working code:
let searchByInts = arrayData.filter { $0.values.contains { $0.contains { $0.price > 2000 } } }
By the way please write the following using literals:
var arrayData : [[String : [BottleModel]]] = []
Still no idea if that is what you actually want because your goal is very unclear. You have an array of dictionaries of arrays which actually contain the values you want to filter out. If a BottleModel costs more than 2000 do you want to keep the entire array it is contained in and the dictionary that array is in? You might want to map the entire data into one flat array before or after filtering.
Alternative using flatMap:
let flat = arrayData.flatMap { $0.values.flatMap { $0 } }
let searchByInts2 = flat.filter { $0.price < 200 } // or some other criteria

Cannot add an append an array into a dictionary that has an empty array

I have a Profile Data singleton class as follows.
I am trying to store data into an empty array in a dictionary .
After appending data to the array also the count of the array is 0.
class ProfileData{
static let sharedInstance = ProfileData()
var artistProfileDict = [String : Profile]()
var loggedInUserProfile = Profile(artistName: "John Smith", artistDescription: "Admiral of New England, English soldier, explorer, and author.", totalLikes: "174", totalViews: "200", totalFollowing: "100",totalFollowers:"50",imageUrl:"image_singer", feeds:[] )
private init() {
getProfilesDictionary()
}
func getProfilesDictionary()->[String: Profile]{
artistProfileDict["John Smith"] = loggedInUserProfile
return artistProfileDict
}
func add(array: Feed, artistName: String) {
artistProfileDict[artistName]!.feeds.append(array)
}
}
In another view Controller I am trying to add an array to the empty array in the dictionary as follows
let newFeed = Feed(profilePicture: "image",artistName: "New",
videoUrl: "url",videoTitle:"New", videoViews: "160",likes:
"200",shoutouts: "200",comments: [],votes: "50", dateCreated: Date(),
userActivity :"This user liked your video")
ProfileData.sharedInstance.add(array: newFeed,artistName:"John Smith")
After appending the array to the empty array in the dictionary I still get the count of the array as 0.
I am not able to figure out the problem here. Any help will appreciated . Thank you.
Profile class
struct Profile {
var artistName: String
var artistDescription: String
var totalLikes: String
var totalViews: String
var totalFollowing: String
var totalFollowers: String
var imageUrl: String
var feeds : [Feed]
init(artistName: String,artistDescription:String,totalLikes:String,totalViews:String,totalFollowing:String,totalFollowers:String,imageUrl:String, feeds:[Feed]) {
self.artistName = artistName
self.artistDescription = artistDescription
self.totalLikes = totalLikes
self.totalViews = totalViews
self.totalFollowing = totalFollowing
self.totalFollowers = totalFollowers
self.imageUrl = imageUrl
self.feeds = feeds
}
}
It's working fine
ProfileData.sharedInstance.add(array: newFeed,artistName:"John Smith")
ProfileData.sharedInstance.artistProfileDict["John Smith"]?.feeds.count // 1
Probably you are using wrong class ArtistProfileData instead of ProfileData.

Create Dictionary<String, [SomeStruct]> from [SomeStruct] source-array

var sourceEntries: [Entry] = [entry1, ..., entry14]
var myDict: Dictionary<String, [Entry]> = [:]
for entry in sourceEntries {
if var array = myDict[entry.attribute1] { theArray.append(entry) }
else { myDict[entry.attribute1] = [entry] }
}
I am intending to create a Dictionary, which matches all the objects of the struct "Eintrag" with the same attribute from the source-Array "alleEinträge" to a String containing the value of the shared attribute. For some reason my final Dictionary just matches Arrays of one element to the Strings, although some Arrays ought to contain up to four elements.
The problem is that the array is passed by value (i.e. "copied"), so the array you are writing to when you say array.append is not the array that is "inside" the dictionary. You have to write back into the dictionary explicitly if you want to change what's in it.
Try it in a simple situation:
var dict = ["entry":[0,1,2]]
// your code
if var array = dict["entry"] { array.append(4) }
// so what happened?
println(dict) // [entry: [0, 1, 2]]
As you can see, the "4" never got into the dictionary.
You have to write back into the dictionary explicitly:
if var array = dict["entry"] { array.append(4); dict["entry"] = array }
FURTHER THOUGHTS: You got me thinking about whether there might be a more elegant way to do what you're trying to do. I'm not sure whether you will think this is "more elegant", but perhaps it has some appeal.
I will start by setting up a struct (like your Entry) with a name attribute:
struct Thing : Printable {
var name : String
var age : Int
var description : String {
return "{\(self.name), \(self.age)}"
}
}
Now I will create an array like your sourceEntries array, where some of the structs share the same name (like your shared attribute attribute1):
let t1 = Thing(name: "Jack", age: 40)
let t2 = Thing(name: "Jill", age: 38)
let t3 = Thing(name: "Jill", age: 37)
let arr = [t1,t2,t3]
And of course I will prepare the empty dictionary, like your myDict, which I call d:
var d = [String : [Thing]]()
Now I will create the dictionary! The idea is to use map and filter together to do all the work of creating key-value pairs, and then we just build the dictionary from those pairs:
let pairs : [(String, [Thing])] = arr.map {
t in (t.name, arr.filter{$0.name == t.name})
}
for pair in pairs { d[pair.0] = pair.1 }

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