How to: Show a Current Location on a Map

using DevExpress.ExpressApp;
using DevExpress.ExpressApp.Maps.Mobile;
using DevExpress.ExpressApp.Maps.Mobile.Editors;
//...
public class ShowCurrentLocationController : ViewController<ListView> {
    public ShowCurrentLocationController() {
        TargetViewId = "MapsMarker_ListView";
    }
    protected override void OnViewControlsCreated() {
        base.OnViewControlsCreated();
        MobileMapsListEditor mobileMapsListEditor = View.Editor as MobileMapsListEditor;
        if (mobileMapsListEditor != null) {
            Map map = mobileMapsListEditor.Control as Map;
            map.OnCustomize = GetCustomizeScript();
        }
    }
    private string GetCustomizeScript() {
        return
        @"(function(mapInstance) {
            mapInstance.on('ready', function(e) {
                var googleMap = e.originalMap;    
                var showError = (function(errorText) {
                    DevExpress.ui.notify({ closeOnClick: true, message: errorText, type: 'error' }, 'error', 5000);
                });                        
                if (navigator.geolocation) {
                    navigator.geolocation.getCurrentPosition(function(position) {
                        var pos = {
                            lat: position.coords.latitude,
                            lng: position.coords.longitude
                        };
                        var infoWindow = new google.maps.InfoWindow({map: googleMap});
                        infoWindow.setPosition(pos);
                        infoWindow.setContent('Current location.');
                        googleMap.setCenter(pos);
                    }, 
                    function(error) {
                        var errorText = '';
                        switch(error.code) {
                            case error.PERMISSION_DENIED:
                                errorText = 'User denied the request for Geolocation.'
                                break;
                            case error.POSITION_UNAVAILABLE:
                                errorText = 'Location information is unavailable.'
                                break;
                            case error.TIMEOUT:
                                errorText = 'The request to get user location timed out.'
                                break;
                            case error.UNKNOWN_ERROR:
                                errorText = 'An unknown error occurred.'
                                break;
                        }
                        showError(errorText);                            
                    });
                } else { showError('Your browser does not support geolocation'); }
            });
        })";
    }
}

Imports Microsoft.VisualBasic
Imports DevExpress.ExpressApp
Imports DevExpress.ExpressApp.Maps.Mobile
Imports DevExpress.ExpressApp.Maps.Mobile.Editors
'...
Public Class ShowCurrentLocationController
    Inherits ViewController(Of ListView)

    Public Sub New()
        TargetViewId = "MapsMarker_ListView"
    End Sub
    Protected Overrides Sub OnViewControlsCreated()
        MyBase.OnViewControlsCreated()
        Dim mobileMapsListEditor As MobileMapsListEditor = TryCast(View.Editor, MobileMapsListEditor)
        If mobileMapsListEditor IsNot Nothing Then
            Dim map As Map = TryCast(mobileMapsListEditor.Control, Map)
            map.OnCustomize = GetCustomizeScript()
        End If
    End Sub
    Private Function GetCustomizeScript() As String
        Return "(function(mapInstance) {" & ControlChars.CrLf & _
"            mapInstance.on('ready', function(e) {" & ControlChars.CrLf & _
"                var googleMap = e.originalMap;    " & ControlChars.CrLf & _
"                var showError = (function(errorText) {" & ControlChars.CrLf & _
"                    DevExpress.ui.notify({ closeOnClick: true, message: errorText, type: 'error' }, 'error', 5000);" & ControlChars.CrLf & _
"                });                        " & ControlChars.CrLf & _
"                if (navigator.geolocation) {" & ControlChars.CrLf & _
"                    navigator.geolocation.getCurrentPosition(function(position) {" & ControlChars.CrLf & _
"                        var pos = {" & ControlChars.CrLf & _
"                            lat: position.coords.latitude," & ControlChars.CrLf & _
"                            lng: position.coords.longitude" & ControlChars.CrLf & _
"                        };" & ControlChars.CrLf & _
"                        var infoWindow = new google.maps.InfoWindow({map: googleMap});" & ControlChars.CrLf & _
"                        infoWindow.setPosition(pos);" & ControlChars.CrLf & _
"                        infoWindow.setContent('Current location.');" & ControlChars.CrLf & _
"                        googleMap.setCenter(pos);" & ControlChars.CrLf & _
"                    }, " & ControlChars.CrLf & _
"                    function(error) {" & ControlChars.CrLf & _
"                        var errorText = '';" & ControlChars.CrLf & _
"                        switch(error.code) {" & ControlChars.CrLf & _
"                            case error.PERMISSION_DENIED:" & ControlChars.CrLf & _
"                                errorText = 'User denied the request for Geolocation.'" & ControlChars.CrLf & _
"                                break;" & ControlChars.CrLf & _
"                            case error.POSITION_UNAVAILABLE:" & ControlChars.CrLf & _
"                                errorText = 'Location information is unavailable.'" & ControlChars.CrLf & _
"                                break;" & ControlChars.CrLf & _
"                            case error.TIMEOUT:" & ControlChars.CrLf & _
"                                errorText = 'The request to get user location timed out.'" & ControlChars.CrLf & _
"                                break;" & ControlChars.CrLf & _
"                            case error.UNKNOWN_ERROR:" & ControlChars.CrLf & _
"                                errorText = 'An unknown error occurred.'" & ControlChars.CrLf & _
"                                break;" & ControlChars.CrLf & _
"                        }" & ControlChars.CrLf & _
"                        showError(errorText);                            " & ControlChars.CrLf & _
"                    });" & ControlChars.CrLf & _
"                } else { showError('Your browser does not support geolocation'); }" & ControlChars.CrLf & _
"            });" & ControlChars.CrLf & _
"        })"
    End Function
End Class