MapView

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Android.App;
using Android.Content;
using Android.Gms.Maps.Model;
using Android.Gms.Maps;
using Android.Graphics;
using Android.Graphics.Drawables;
using Android.OS;
using Android.Runtime;
using Android.Support.V4.App;
using Android.Util;
using Android.Views;
using Android.Widget;
using HyperLocal.Common;

namespace HyperLocal.Demo.Xamdroid
{
    public class MapFragment : Fragment, GoogleMap.IOnInfoWindowClickListener, GoogleMap.IOnCameraChangeListener, GoogleMap.IOnMarkerClickListener
    {
        List<MarkerInfo> pois = new List<MarkerInfo>();

        private Dictionary<string, MarkerInfo> currentMarkerInfos = new Dictionary<string, MarkerInfo>();
        private MapView mapView;
        private GoogleMap map;

        bool firstLoadWithLocation = true;
        bool shouldAllowCameraChange = true;

        public override View OnCreateView(LayoutInflater layoutInflater, ViewGroup viewGroup, Bundle bundle)
        {
            var view = layoutInflater.Inflate(Resource.Layout.MapDialogFragment, viewGroup, false);


            mapView = view.FindViewById<MapView>(Resource.Id.map);

            mapView.OnCreate(bundle);

            try
            {
                MapsInitializer.Initialize(this.Activity);
            }
            catch (Exception ex)
            {
                Android.Util.Log.Error("ARDEMO", ex.ToString());
            }

            map = mapView.Map;

            map.UiSettings.MyLocationButtonEnabled = true;

            map.SetLocationSource((MainActivity)this.Activity);

            map.SetOnCameraChangeListener (this);
            map.SetOnInfoWindowClickListener(this);
            map.SetOnMarkerClickListener (this);
            Common.Log.Debug("MapFragment->OnCreateView");


            var cu = CameraUpdateFactory.NewCameraPosition(new CameraPosition(new LatLng(PoiService.Instance.CurrentLatitude, PoiService.Instance.CurrentLongitude), 16, 0, 0));
            map.MoveCamera(cu);

            return view;
        }

        public bool OnMarkerClick(Marker marker)
        {
            shouldAllowCameraChange = false;
            Common.Log.Debug ("MapFragment->MarkerClick");
            return false;
        }

        public void OnInfoWindowClick(Marker marker)
        {
            Common.Log.Debug ("MapFragment->OnInfoWindowClick");

            if (currentMarkerInfos.ContainsKey(marker.Id))
            {
                Common.Log.Debug("Marker InfoWindow Clicked: " + marker.Id);

                var markerInfo = currentMarkerInfos[marker.Id];

                var ddf = new DetailsDialogFragment() { Item = markerInfo };
                ddf.Show(this.Activity.SupportFragmentManager, "MDF");
            }

        }

        public async void OnCameraChange (CameraPosition cameraPos)
        {
            Common.Log.Debug ("MapFragment->CameraChange");

            if (!shouldAllowCameraChange) {
                shouldAllowCameraChange = true;
                return;
            }

            var llb = map.Projection.VisibleRegion.LatLngBounds;
            var visibleRadius = GeoMath.Distance (llb.Northeast.Latitude, llb.Northeast.Longitude, llb.Southwest.Latitude, llb.Southwest.Longitude, GeoMath.MeasureUnits.Kilometers);

            var radius = GeoMath.KmToDegrees (visibleRadius);


            var lat = cameraPos.Target.Latitude;
            var lng = cameraPos.Target.Longitude;

            var markers = await PoiService.Instance.SearchAsync (null, lat, lng, radius);

                this.pois.Clear();
                this.pois.AddRange(markers);

            try { UpdatePois(); } catch { }
        }


        void UpdatePois()
        {
            this.Activity.RunOnUiThread(() => map.Clear());

            currentMarkerInfos.Clear();

            Console.WriteLine("POIS MAP VIEW: " + pois.Count());

            foreach (var p in pois)
            {
                var mo = new MarkerOptions();
                mo.SetPosition(new LatLng(p.Latitude, p.Longitude));
                mo.SetTitle(p.Name);
                mo.SetSnippet(p.Category);

                this.Activity.RunOnUiThread(() =>
                {
                    var addedMarker = map.AddMarker(mo);

                    if (addedMarker == null)
                        Console.WriteLine("Added Marker is null");
                    else
                        currentMarkerInfos.Add(addedMarker.Id, p);
                });
            }
        }

        public void MoveCamera(double latitude, double longitude)
        {
            firstLoadWithLocation = false;

            var cu = CameraUpdateFactory.NewCameraPosition(new CameraPosition(new LatLng(latitude, longitude), 16, 0, 0));
            map.AnimateCamera(cu, 1, null);
        }

        public override void OnResume()
        {
            Common.Log.Debug("MapFragment->OnResume");

            mapView.OnResume();
            base.OnResume();

            map.MyLocationEnabled = true;

            UpdatePois();
        }

        public override void OnDestroy()
        {
            Common.Log.Debug("MapFragment->OnDestroy");

            mapView.OnDestroy();
            base.OnDestroy();
        }

        public override void OnLowMemory()
        {
            mapView.OnLowMemory();
            base.OnLowMemory();
        }
    }
}