Tukukkk

I am facing a problem in getting the values to make the desired combination. I am using a filter screen in my app. I asked this question to get the first and last element from the question How to put the of first and last element of Array in Swift and it is working but the problem is in my FiterVC first I selected the option $400 - $600 and then I selected the $200 - $400. After selecting I am getting these values in my currentFilter variable.

private let menus = [



    ["title": "Price", "isMultiSelection": true, "values": [

        ["title": "$00.00 - $200.00"],

        ["title": "$200.00 - $400.00"],

        ["title": "$400.00 - $600.00"],

        ["title": "$600.00 - $800.00"],

        ["title": "$800.00 - $1000.00"],

        ]],

    ["title": "Product Rating", "isMultiSelection": true, "values": [

        ["title": "5"],

        ["title": "4"],

        ["title": "3"],

        ["title": "2"],

        ["title": "1"]

        ]],

    ["title": "Arriving", "isMultiSelection": true, "values": [

        ["title": "New Arrivials"],

        ["title": "Coming Soon"]

        ]]

]



private var currentFilters = [String:Any]()

Selecting values in didSelect method:-

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

    if tableView === self.menuTableView {

        self.currentSelectedMenu = indexPath.row

        self.menuTableView.reloadData()

        self.valueTableView.reloadData()

    }

    else {

        if let title = self.menus[self.currentSelectedMenu]["title"] as? String, let values = self.menus[self.currentSelectedMenu]["values"] as? [[String:Any]], let obj = values[indexPath.row]["title"] as? String {

            if let old = self.selectedFilters[title] as? [String], let isAllowedMulti = self.menus[self.currentSelectedMenu]["isMultiSelection"] as? Bool, !old.isEmpty, !isAllowedMulti {

                var temp = old

                if old.contains(obj), let index = old.index(of: obj) {

                    temp.remove(at: index)

                }

                else {

                    temp.append(obj)     

                }

                self.selectedFilters[title] = temp

            }

            else {

                self.selectedFilters[title] = [obj]

            }

            self.valueTableView.reloadData()

        }

    }

}

And on Apply button click:-

@IBAction func applyButtonAction(_ sender: UIButton) {

    self.delegate?.didSelectedFilters(self, with: self.selectedFilters)

    printD(self.selectedFilters)

    self.dismiss(animated: true, completion: nil)

}

When I am printing the selectedFilters I am getting these values:-

currentFilters ["Price": ["$400.00 - $600.00", "$200.00 - $400.00"]]

And by using this method I am getting the first and last value from dictionary like this:-

if let obj = currentFilters["Price"] as? [String] {

   self.priceRange = obj

   printD(self.priceRange)



   let first = priceRange.first!.split(separator: "-").first!

   let last = priceRange.last!.split(separator: "-").last!

   let str = "(first)-(last)"

   let str2 = str.replacingOccurrences(of: "$", with: "", options: NSString.CompareOptions.literal, range: nil)

   newPrice = str2

   printD(newPrice)

}

The result is :-

400.00 - 400.00

but what I actually want is 200 - 600. How can I do this. Please help?

However there are many solutions available to this problem but simplest and most relevant solution is highlighted here:

let min = 1000, max = 0

if let obj = currentFilters["Price"] as? [String] {

   self.priceRange = obj

   printD(self.priceRange)



   for str in obj{

     let first = str.split(separator: "-").first!.replacingOccurrences(of: "$", with: "", options:

            NSString.CompareOptions.literal, range: nil)

     let last = str.split(separator: "-").last!.replacingOccurrences(of: "$", with: "", options:

            NSString.CompareOptions.literal, range: nil)

     if Int(first) < min{

       min = first

     }

     if Int(last) > max{

       max = last

     }

   }

   let str = "(min)-(max)"

   newPrice = str

   printD(newPrice)

}

In my opinion you should be storing all the relevant filtering information in separate classes. You should change them to proper structured data as soon as you get them as strings. (If you are creating them yourself, then you shouldn't be having them as strings for any reason)

class PriceRange {

    var minValue: Int

    var maxValue: Int



    init(_ minValue: Int, _ maxValue: Int) {

        self.minValue = minValue

        self.maxValue = maxValue

    }

}



class ProductRating { // Relevant naming

    // Relevant parameters

}



class Arriving { // Relevant naming

    // Relevant parameters

}



// The class whose object which store the filtered information

class Filters {

    var priceRange: [PriceRange]

    var productRating: [ProductRating] // Change as necessary

    var arriving: [Arriving] // Change as necessary



    init(priceRange: [PriceRange], productRating: [ProductRating], arriving: [Arriving]) {

        self.priceRange = priceRange

        self.productRating = productRating

        self.arriving = arriving

    }

}

Now if you manage to get the filtersApplied by filtering the default set of array of filters. You would have something like this.

var filteredPriceRanges = [PriceRange(400, 600), PriceRange(200, 400)] // Example

var filtersApplied = Filters(priceRange: filteredPriceRanges, productRating: /* filtered product rating */, arriving: /* filtered arriving information */)

let selectedRanges = filtersApplied.priceRange

Now all you need to do is reduce it to the minimum and maximum range.

let finalRange = selectedRanges.reduce(PriceRange(selectedRanges.first?.minValue ?? 0, selectedRanges.first?.maxValue ?? 0)) { (result, range) -> PriceRange in

    if result.minValue > range.minValue {

        result.minValue = range.minValue

    }

    if result.maxValue < range.maxValue {

        result.maxValue = range.maxValue

    }

    return result

}



// Note this returns (0, 0) if none of the filters are selected. So make sure you have some way of enforcing the use has atleast one filter selected

You can use an enum with functions to load your prices ranges instead of using directly Strings.

enum PriceRange: String {

    case

    low     = "200 - 400",

    high    = "400 - 600"



    static let priceRanges = [low, high]



    func getStringValue() -> String {

        return self.rawValue

    }



    func getMinValueForRange(stringRange: String) -> Int? {

        switch stringRange {

        case "200 - 400":

            return 200;



        case "400 - 600":

            return 400;

        default:

            return nil

        }

    }



    func getMaxValueForRange(stringRange: String) -> Int? {

        switch stringRange {

        case "200 - 400":

            return 400;



        case "400 - 600":

            return 600;

        default:

            return nil

        }

    }



}

Then you can use/add functions to get the result that you are looking for.

Here's the small solution of your problem. It all breaks down to that: you get all the values from your filters, and then iterating over getting all the values from it. That way you avoid comparing the pairs and instead comparing the exact values.

let currentFilters =  ["Price": ["$400.00 - $600.00", "$200.00 - $400.00"]]

let ranges = currentFilters["Price"]!

var values: [Double] = 

ranges.forEach { range in // iterate over each range

    let rangeValues = range.split(separator: "-")

    for value in rangeValues { // iterate over each value in range

        values.append(Double( // cast string value to Double

            String(value)

                .replacingOccurrences(of: " ", with: "")

                .replacingOccurrences(of: "$", with: "")

        )!)

    }

}



let min = values.min() // prints 200

let max = values.max() // prints 600