Jules Lee 
If you’re a newbie on this, you might not actually figure this out quick. Apparently, it’s only a quick tour to the example project in Eureka. Particularly in CustomCells.swift. Just create a file and copy the last code below or from the link if the repository gets updated.
<<< LocationRow(){
$0.title = "Location"
$0.value = CLLocation(latitude: latitude, longitude: longitude)
$0.tag = "location"
$0.validationOptions = .validatesOnChange //2
$0.cellUpdate { (cell, row) in //3
if !row.isValid {
cell.textLabel?.textColor = .red
} else {
let lastLocation = row.value
let geocoder = CLGeocoder()
geocoder.reverseGeocodeLocation(lastLocation!,
completionHandler: { (placemarks, error) in
if error == nil {
let place = placemarks![0]
var adressString : String = ""
if place.thoroughfare != nil {
adressString = adressString + place.thoroughfare! + ", "
}
if place.subThoroughfare != nil {
adressString = adressString + place.subThoroughfare! + " "
}
if place.locality != nil {
adressString = adressString + place.locality! + " - "
}
if place.postalCode != nil {
adressString = adressString + place.postalCode! + " "
}
if place.subAdministrativeArea != nil {
adressString = adressString + place.subAdministrativeArea! + " - "
}
if place.country != nil {
adressString = adressString + place.country!
}
self.address = adressString.trimmingCharacters(in: .whitespacesAndNewlines)
}
})
}
}
}
The code above is how I implemented LocationRow in my form. You’ll see from here that I used a Geocoder in order to formulate an address string from the coordinates selected to a variable in the ViewController called address. If you don’t need this feature, just get rid of what’s after else.
import Foundation
import UIKit
import MapKit
import Eureka
//MARK: LocationRow
public final class LocationRow: OptionsRow<PushSelectorCell<CLLocation>>, PresenterRowType, RowType {
public typealias PresenterRow = MapViewController
/// Defines how the view controller will be presented, pushed, etc.
public var presentationMode: PresentationMode<PresenterRow>?
/// Will be called before the presentation occurs.
public var onPresentCallback: ((FormViewController, PresenterRow) -> Void)?
public required init(tag: String?) {
super.init(tag: tag)
presentationMode = .show(controllerProvider: ControllerProvider.callback { return MapViewController(){ _ in } }, onDismiss: { vc in _ = vc.navigationController?.popViewController(animated: true) })
displayValueFor = {
guard let location = $0 else { return "" }
let fmt = NumberFormatter()
fmt.maximumFractionDigits = 4
fmt.minimumFractionDigits = 4
let latitude = fmt.string(from: NSNumber(value: location.coordinate.latitude))!
let longitude = fmt.string(from: NSNumber(value: location.coordinate.longitude))!
return "\(latitude), \(longitude)"
}
}
/**
Extends `didSelect` method
*/
public override func customDidSelect() {
super.customDidSelect()
guard let presentationMode = presentationMode, !isDisabled else { return }
if let controller = presentationMode.makeController() {
controller.row = self
controller.title = selectorTitle ?? controller.title
onPresentCallback?(cell.formViewController()!, controller)
presentationMode.present(controller, row: self, presentingController: self.cell.formViewController()!)
} else {
presentationMode.present(nil, row: self, presentingController: self.cell.formViewController()!)
}
}
/**
Prepares the pushed row setting its title and completion callback.
*/
public override func prepare(for segue: UIStoryboardSegue) {
super.prepare(for: segue)
guard let rowVC = segue.destination as? PresenterRow else { return }
rowVC.title = selectorTitle ?? rowVC.title
rowVC.onDismissCallback = presentationMode?.onDismissCallback ?? rowVC.onDismissCallback
onPresentCallback?(cell.formViewController()!, rowVC)
rowVC.row = self
}
}
public class MapViewController : UIViewController, TypedRowControllerType, MKMapViewDelegate {
public var row: RowOf<CLLocation>!
public var onDismissCallback: ((UIViewController) -> ())?
lazy var mapView : MKMapView = { [unowned self] in
let v = MKMapView(frame: self.view.bounds)
v.autoresizingMask = [.flexibleWidth, .flexibleHeight]
return v
}()
lazy var pinView: UIImageView = { [unowned self] in
let v = UIImageView(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
v.image = UIImage(named: "map_pin", in: Bundle(for: MapViewController.self), compatibleWith: nil)
v.image = v.image?.withRenderingMode(.alwaysTemplate)
v.tintColor = self.view.tintColor
v.backgroundColor = .clear
v.clipsToBounds = true
v.contentMode = .scaleAspectFit
v.isUserInteractionEnabled = false
return v
}()
let width: CGFloat = 10.0
let height: CGFloat = 5.0
lazy var ellipse: UIBezierPath = { [unowned self] in
let ellipse = UIBezierPath(ovalIn: CGRect(x: 0, y: 0, width: self.width, height: self.height))
return ellipse
}()
lazy var ellipsisLayer: CAShapeLayer = { [unowned self] in
let layer = CAShapeLayer()
layer.bounds = CGRect(x: 0, y: 0, width: self.width, height: self.height)
layer.path = self.ellipse.cgPath
layer.fillColor = UIColor.gray.cgColor
layer.fillRule = .nonZero
layer.lineCap = .butt
layer.lineDashPattern = nil
layer.lineDashPhase = 0.0
layer.lineJoin = .miter
layer.lineWidth = 1.0
layer.miterLimit = 10.0
layer.strokeColor = UIColor.gray.cgColor
return layer
}()
required public init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
public override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
super.init(nibName: nil, bundle: nil)
}
convenience public init(_ callback: ((UIViewController) -> ())?){
self.init(nibName: nil, bundle: nil)
onDismissCallback = callback
}
public override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(mapView)
mapView.delegate = self
mapView.addSubview(pinView)
mapView.layer.insertSublayer(ellipsisLayer, below: pinView.layer)
let button = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(MapViewController.tappedDone(_:)))
button.title = "Done"
navigationItem.rightBarButtonItem = button
if let value = row.value {
let region = MKCoordinateRegion(center: value.coordinate, latitudinalMeters: 400, longitudinalMeters: 400)
mapView.setRegion(region, animated: true)
}
else{
mapView.showsUserLocation = true
}
updateTitle()
}
public override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
let center = mapView.convert(mapView.centerCoordinate, toPointTo: pinView)
pinView.center = CGPoint(x: center.x, y: center.y - (pinView.bounds.height/2))
ellipsisLayer.position = center
}
@objc func tappedDone(_ sender: UIBarButtonItem){
let target = mapView.convert(ellipsisLayer.position, toCoordinateFrom: mapView)
row.value = CLLocation(latitude: target.latitude, longitude: target.longitude)
onDismissCallback?(self)
}
func updateTitle(){
let fmt = NumberFormatter()
fmt.maximumFractionDigits = 4
fmt.minimumFractionDigits = 4
let latitude = fmt.string(from: NSNumber(value: mapView.centerCoordinate.latitude))!
let longitude = fmt.string(from: NSNumber(value: mapView.centerCoordinate.longitude))!
title = "\(latitude), \(longitude)"
}
public func mapView(_ mapView: MKMapView, regionWillChangeAnimated animated: Bool) {
ellipsisLayer.transform = CATransform3DMakeScale(0.5, 0.5, 1)
UIView.animate(withDuration: 0.2, animations: { [weak self] in
self?.pinView.center = CGPoint(x: self!.pinView.center.x, y: self!.pinView.center.y - 10)
})
}
public func mapView(_ mapView: MKMapView, regionDidChangeAnimated animated: Bool) {
ellipsisLayer.transform = CATransform3DIdentity
UIView.animate(withDuration: 0.2, animations: { [weak self] in
self?.pinView.center = CGPoint(x: self!.pinView.center.x, y: self!.pinView.center.y + 10)
})
updateTitle()
}
}
Custom Table Cell With SwiftUI