Maps Providers in Xamarin Maps (SfMaps)

The maps control supports map providers such as OpenStreetMap and Bing Maps that can be added to an imagery layer in maps.

OpenStreetMap

The OpenStreetMap (OSM) is a world map; it was built by a community of mappers. It is free to use under an open license. This allows you to view geographical data in a collaborative way from anywhere on the earth. The OSM provides small tile images based on your requests and combines them into a single image to display the map area in the maps control.

Adding OSM in maps

The maps control uses imagery layer to display the tile images from the OSM service. To use OSM, add an imagery layer in maps’ layers collection.

<maps:SfMaps.Layers>
            <maps:ImageryLayer/>
        </maps:SfMaps.Layers>
SfMaps maps = new SfMaps();
        ImageryLayer layer = new ImageryLayer();
        maps.Layers.Add(layer);

Xamarin OSM image

NOTE

Both the ShapeFileLayer and ImageryLayer have been derived commonly from MapsLayer.

Bing Maps

The Bing Maps is a world map owned by Microsoft. As OSM, Bing Maps also provides the map tile images based on your requests and combines them into a single image to display the map area. To use Bing maps, set the LayerType property of ImageryLayer to “Bing”. Then, set the Bing Maps key, which is obtained from Bing Maps Key.

<maps:SfMaps.Layers>
        <maps:ImageryLayer LayerType="Bing" BingMapKey="Your bing map key"/>
    </maps:SfMaps.Layers>
SfMaps maps = new SfMaps();
    ImageryLayer layer = new ImageryLayer();
    layer.LayerType = LayerType.Bing;
    layer.BingMapKey = "Your bing map key";
    maps.Layers.Add(layer);

Xamarin Bing road image

NOTE

The LayerType property of ImageryLayer provides the support to OSM and Bing Maps. The default value of the LayerType property is OSM.

Set different bing map style

The ImageryLayer provides the support to the following types of Bing Maps:

  • Road
  • Aerial
  • AerialWithLabels

The desired style for the Bing Maps can be set using the BingMapStyle property of ImageryLayer. The default value of BingMapStyle is “Road”.

Road

The Road view displays the default map view of roads, buildings, and geography. The default value of the BingMapStyle property of imagery layer is “Road”.

Aerial

The Aerial view displays the satellite images to highlight the roads and major landmarks for easy identification. The aerial view can be applied to maps by setting the BingMapStyle to “Aerial”.

<maps:SfMaps.Layers>
            <maps:ImageryLayer LayerType="Bing" 
                            BingMapStyle="Aerial"
                            BingMapKey=" Your bing map key "/>
        </maps:SfMaps.Layers>
SfMaps maps = new SfMaps();
        ImageryLayer layer = new ImageryLayer();
        layer.LayerType = LayerType.Bing;
        layer.BingMapStyle = BingMapStyle.Aerial;
        layer.BingMapKey = "Your bing map key ";
        maps.Layers.Add(layer);

Xamarin Bing aerial image

AerialWithLabel

The AerialWithLabel view displays the Aerial map with labels for continent, country, ocean, etc. This view can be applied to maps by setting the BingMapStyle to “AerialWithLabel”.

<maps:SfMaps.Layers>
            <maps:ImageryLayer LayerType="Bing" 
                            BingMapStyle="AerialWithLabels"
                            BingMapKey=" Your bing map key "/>
        </maps:SfMaps.Layers>
SfMaps maps = new SfMaps();
        ImageryLayer layer = new ImageryLayer();
        layer.LayerType = LayerType.Bing;
        layer.BingMapStyle = BingMapStyle.AerialWithLabels;
        layer.BingMapKey = "Your bing map key ";
        maps.Layers.Add(layer);

Xamarin Bing aerialwithlabel image

Zooming and panning

The maps control provides the interactive zooming and panning supports to OSM and Bing Maps.

Zooming helps you to get a closer look of an area on maps for in-depth analysis. Panning helps you to move a map around to focus the targeted area. You can perform zooming and panning with the pinching gesture in a map area.

Xamarin Zooming image

Reset zooming

The ImageryLayer provides the support to reset the maps to the default view when you double tap the imagery layer by setting the ResetOnDoubleTap property to true. The default value of this property is true. This behavior can be restricted by setting the ResetOnDoubleTap property to false.

<maps:SfMaps>
        <maps:SfMaps.Layers>
                <maps:ImageryLayer ResetOnDoubleTap="True"/>
            </maps:SfMaps.Layers>
        </maps:SfMaps>
SfMaps maps = new SfMaps();
        ImageryLayer layer = new ImageryLayer();
        layer.ResetOnDoubleTap = true;
        maps.Layers.Add(layer);

Set Geo coordinates points(center position)

The GeoCoordinates(center) property allows you view the desired area at the center on loading. By default, the GeoCoordinates value is (0,0). So, first parameter of the latitude value “0” and second parameter of the longitude value “0” are shown at the center.

<maps:SfMaps ZoomLevel="2">
                <maps:SfMaps.Layers>
                    <maps:ImageryLayer GeoCoordinates="69.07,-37.08"/>
                </maps:SfMaps.Layers>
            </maps:SfMaps>
SfMaps maps = new SfMaps();
  maps.ZoomLevel = 2;
  ImageryLayer layer = new ImageryLayer();
  layer.GeoCoordinates = new Point(69.07, -37.08);
  maps.Layers.Add(layer);

Xamarin Coordinate image

<maps:SfMaps ZoomLevel="2">
            <maps:SfMaps.Layers>
                <maps:ImageryLayer GeoCoordinates="0,0"/>
            </maps:SfMaps.Layers>
        </maps:SfMaps>
SfMaps maps = new SfMaps();
  maps.ZoomLevel = 2;
  ImageryLayer layer = new ImageryLayer();
  layer.GeoCoordinates = new Point(0,0);
  maps.Layers.Add(layer);

Xamarin center image

Set markers in imagery layer

As ShapeFileLayer, markers also can be added to imagery layer. Markers can be customized using the MarkerSettings property in imagery layer.
The detailed explanation of marker and its customization have been provided in Markers section.

<maps:ImageryLayer  >
            <maps:ImageryLayer.MarkerSettings>
                <maps:MapMarkerSetting IconColor="Red" 
                                    IconSize="13" MarkerIcon="Diamond"/>
            </maps:ImageryLayer.MarkerSettings>
                        <maps:ImageryLayer.Markers>
                            <maps:MapMarker  Label="United States" Latitude="40"
                                            Longitude= "-101"/>
                            <maps:MapMarker Label="Brazil" Latitude="-15.7833" 
                                            Longitude= "-52" />
                            <maps:MapMarker Label="Congo" Latitude="-1.6" 
                                            Longitude= "24.4" />
                            <maps:MapMarker Label="Kazakhstan" Latitude="49.9" 
                                            Longitude= "72.23" />
                            <maps:MapMarker Label="Australia" Latitude="-20.54"
                                            Longitude= "134.10" />
                    </maps:ImageryLayer.Markers>
                </maps:ImageryLayer>
ImageryLayer layer = new ImageryLayer();
            layer.MarkerSettings = new MapMarkerSetting();
            layer.MarkerSettings.IconColor = Color.Red;
            layer.MarkerSettings.MarkerIcon = MapMarkerIcon.Diamond;
            layer.MarkerSettings.IconSize = 13;
            MapMarker marker1 = new MapMarker();
            marker1.Label = "United States";
            marker1.Latitude = "40";
            marker1.Longitude = "-101";
            layer.Markers.Add(marker1);
            MapMarker marker2 = new MapMarker();
            marker2.Label = "Brazil";
            marker2.Latitude = "-15.7833";
            marker2.Longitude = "-52";
            layer.Markers.Add(marker2);
            MapMarker marker3 = new MapMarker();
            marker3.Label = "Congo";
            marker3.Latitude = "-1.6";
            marker3.Longitude = "24.4";
            layer.Markers.Add(marker3);
            MapMarker marker4 = new MapMarker();
            marker4.Label = "Kazakhstan";
            marker4.Latitude = "49.9";
            marker4.Longitude = "72.23";
            layer.Markers.Add(marker4);
            MapMarker marker5 = new MapMarker();
            marker5.Label = "Australia";
            marker5.Latitude = "-20.54";
            marker5.Longitude = "134.10";
            layer.Markers.Add(marker5);

Xamarin Marker image

Load custom map

You can load the custom map providers map such as Google Maps, TomTom using the RequestTileUri event of ImageryLayer. For more details about RequestTileUri , refer the Events of ImageryLayer.

<maps:SfMaps>
   <maps:SfMaps.Layers>
         <maps:ImageryLayer RequestTileUri="ImageryLayer_RequestTileUri">
          </maps:ImageryLayer>
    </maps:SfMaps.Layers>
</maps:SfMaps>
SfMaps maps = new SfMaps();
        ImageryLayer layer = new ImageryLayer();
        layer.RequestTileUri += ImageryLayer_RequestTileUri;
        maps.Layers.Add(layer);
        private void ImageryLayer_RequestTileUri(object sender, Syncfusion.SfMaps.XForms.TileUriArgs e)
        {
            var link = "http://mt1.google.com/vt/lyrs=y&x=" + e.X.ToString() + "&y=" + e.Y.ToString() + "&z=" + e.ZoomLevel.ToString();
            e.Uri = link;
        }

See also this KB article to load the google map.

Xamarin custom map provider image

Cache a tile images in application memory

The CanCacheTiles property used to decide whether the tile images should be cached in application memory or not.

ImageryLayer imageryLayer = new ImageryLayer();

       imageryLayer.CanCacheTiles = true;

Calculate a zoom level based on map geo-bounds or distance

This feature is used to calculate the initial zoom level automatically in two ways:

  • Distance in radius(Meter/KiloMeter/Mile)
  • Geo-bounds(Northeast, Southwest)

Distance in radius

Calculate the initial zoom level automatically based on the Radius and DistanceType properties of imagery layer class.

NOTE

DistanceType property default value is KiloMeter.

<ContentPage.Resources>
            <ResourceDictionary>
                <DataTemplate x:Key="markerTemplate">
                    <StackLayout IsClippedToBounds="false" HorizontalOptions="StartAndExpand" VerticalOptions="Center" HeightRequest="35">
                    <Image Source="pin.png" Scale="1" Aspect="AspectFit " HorizontalOptions="StartAndExpand" VerticalOptions="Center"  HeightRequest="35" WidthRequest="25" />
                    </StackLayout>
                </DataTemplate>
            </ResourceDictionary>
        </ContentPage.Resources>

    <maps:SfMaps  x:Name="Map" >
        <maps:SfMaps.Layers >
            <maps:ImageryLayer MarkerSelected="Layer_MarkerSelected" GeoCoordinates = "38.909804, -77.043442" Radius="5" DistanceType="KiloMeter" MarkerTemplate="{StaticResource Key=markerTemplate}">
                <maps:ImageryLayer.Markers>
                    <maps:MapMarker Latitude= "38.909804" Longitude= "-77.043442"/>
                </maps:ImageryLayer.Markers>
            </maps:ImageryLayer>
        </maps:SfMaps.Layers>
    </maps:SfMaps>
SfMaps maps = new SfMaps();
            ImageryLayer layer = new ImageryLayer();
            layer.GeoCoordinates = new Point(38.909804, -77.043442);
            layer.Radius = 5;
            layer.DistanceType = DistanceType.KiloMeter;
            MapMarker marker = new MapMarker();
            marker.Latitude = "38.909804";
            marker.Longitude = "-77.043442";
            layer.MarkerTemplate = this.Resources["markerTemplate"] as DataTemplate;
            layer.Markers.Add(marker);
            maps.Layers.Add(layer);

Xamarin SfMaps zoom level changed image

Geo-bounds

Calculate the initial zoom level automatically based on the LatLngBounds(Northeast, Southwest) of imagery layer class.

<ContentPage.Resources>
        <ResourceDictionary>
            <DataTemplate x:Key="markerTemplate">
                <StackLayout IsClippedToBounds="false" HorizontalOptions="StartAndExpand" VerticalOptions="Center" HeightRequest="35">
                    <Image Source="pin.png" Scale="1" Aspect="AspectFit " HorizontalOptions="StartAndExpand" VerticalOptions="Center"  HeightRequest="35" WidthRequest="25" />
                </StackLayout>
            </DataTemplate>
        </ResourceDictionary>
    </ContentPage.Resources>
    
    <maps:SfMaps>
        <maps:SfMaps.Layers>
            <maps:ImageryLayer MarkerTemplate="{StaticResource Key=markerTemplate}">
                <maps:ImageryLayer.Markers>
                    <maps:MapMarker Latitude= "38.909804" Longitude= "-77.043442"/>
                </maps:ImageryLayer.Markers>
                <maps:ImageryLayer.LatLngBounds>
                    <maps:LatLngBounds>
                        <maps:LatLngBounds.Northeast>
                            <maps:Position>
                                <x:Arguments>
                                    <x:Double>38.909804</x:Double>
                                    <x:Double>-77.043442</x:Double>
                                </x:Arguments>
                            </maps:Position>
                        </maps:LatLngBounds.Northeast>
                        <maps:LatLngBounds.Southwest>
                            <maps:Position>
                                <x:Arguments>
                                    <x:Double>38.909804</x:Double>
                                    <x:Double>-77.043442</x:Double>
                                </x:Arguments>
                            </maps:Position>
                        </maps:LatLngBounds.Southwest>
                    </maps:LatLngBounds>
                </maps:ImageryLayer.LatLngBounds>
            </maps:ImageryLayer>
        </maps:SfMaps.Layers>
    </maps:SfMaps>
SfMaps maps = new SfMaps();
            ImageryLayer layer = new ImageryLayer();
            LatLngBounds bounds = new LatLngBounds();
            bounds.Northeast = new Position(38.909804, -77.043442);
            bounds.Southwest = new Position(38.909804, -77.043442);
            layer.LatLngBounds = bounds;
            MapMarker marker = new MapMarker();
            marker.Latitude = "38.909804";
            marker.Longitude = "-77.043442";
            layer.MarkerTemplate = this.Resources["markerTemplate"] as DataTemplate;
            maps.Layers.Add(layer);

NOTE

When setting LatLngBounds and DistanceRadius at the same time, the priority is DistanceRadius and calculate zoom level based radius value.

Xamarin SfMaps zoom level changed image

Get the map tile layer bounds

You can get imagery layer pixel bounds by using MapBounds property while zooming, panning, and changing Geo-Coordinate value in imagery layer.

<maps:SfMaps >
        <maps:SfMaps.Layers>
            <maps:ImageryLayer x:Name="layer"  GeoCoordinates="30.9709225, -100.2187212" GeoCoordinateChanged="layer_GeoCoordinateChanged">
            </maps:ImageryLayer>
        </maps:SfMaps.Layers>
    </maps:SfMaps>
public partial class MapBound : ContentPage
    {
        ImageryLayer layer = new ImageryLayer();
        public MapBound()
        {
            InitializeComponent();
            SfMaps maps = new SfMaps();
            layer.GeoCoordinates = new Point(30.9709225, -100.2187212);
            layer.GeoCoordinateChanged += Layer_GeoCoordinateChanged;
            maps.Layers.Add(layer);
            this.Content = maps;
        }
        private void Layer_GeoCoordinateChanged(object sender, GeoCoordinateChangedEventArgs e)
        {
            var pixelBounds = layer.MapBounds;
        }
    }

Clear a cached tile images from application memory

The DeleteTilesFromCache method used to clear the cached tile images from application cache memory.

<maps:SfMaps>
            <maps:SfMaps.Layers>            
                <maps:ImageryLayer x:Name="imageryLayer" />
            </maps:SfMaps.Layers>
        </maps:SfMaps>
imageryLayer.DeleteTilesFromCache();

Events

The RequestTileUriArgs event is triggered whenever new tile required for map(such as zooming, panning and initial time).

The following arguments can be obtained from the RequestTileUri event:

  • Uri – Provide the option to set the desired Uri to load the custom map.

  • UriRequestTask – Used to gets or sets the requested uri task asynchronously to load the custom map.

  • X – Used to gets the X Co-ordinate value of the tile image.

  • Y – Used to gets the Y Co-ordinate value of the tile image.

  • ZoomLevel – Used to gets the current zoom level value of the tile image.

<maps:SfMaps>
   <maps:SfMaps.Layers>
         <maps:ImageryLayer RequestTileUri="ImageryLayer_RequestTileUri">
          </maps:ImageryLayer>
    </maps:SfMaps.Layers>
</maps:SfMaps>
private void ImageryLayer_RequestTileUri(object sender, Syncfusion.SfMaps.XForms.TileUriArgs e)
        {
            var link = "http://mt1.google.com/vt/lyrs=y&x=" + e.X.ToString() + "&y=" + e.Y.ToString() + "&z=" + e.ZoomLevel.ToString();
            e.Uri = link;
           
        }

The ZoomLevelChanging event triggers when zoom level changed. Following arguments can be get from the ZoomLevelChanging event .

  • Cancel : Used to cancel the zooming.

  • PreviousLevel : Returns the previous level after the zooming.

  • CurrentLevel : Returns the current level to be zoomed.

<maps:SfMaps>
            <maps:SfMaps.Layers>            
                <maps:ImageryLayer  ZoomLevelChanging="Layer_ZoomLevelChanging" />
            </maps:SfMaps.Layers>
        </maps:SfMaps>
private void Layer_ZoomLevelChanging(object sender, ZoomLevelChangingEventArgs e)
        {
           if(e.PreviousLevel == 10) // Returns the previous zoom level
           {
               e.Cancel = true; // Cancels the zooming event
               var CurrentLevel = e.CurrentLevel; // Returns the current zoomed level
           }
        }

The GeoCoordinateChanged event is triggered while zooming and panning the maps.

The following arguments can be gotten from the ImageryLayer_GeoCoordinateChanged event:

  • Center: Returns the center Geo coordinate point of the visual tiles while zooming and panning.
  • TopLeft: Returns the top-left Geo coordinate point of the visual tiles while zooming and panning.
  • TopRight: Returns the top-right Geo coordinate point of the visual tiles while zooming and panning.
  • BottomLeft: Returns the bottom-left Geo coordinate point of the visual tiles while zooming and panning.
  • BottomRight: Returns the bottom-right Geo coordinate point of the visual tiles while zooming and panning.
<maps:SfMaps >
    <maps:SfMaps.Layers >
        <maps:ImageryLayer GeoCoordinateChanged="ImageryLayer_GeoCoordinateChanged"/>       
    </maps:SfMaps.Layers>
</maps:SfMaps>
private void ImageryLayer_GeoCoordinateChanged(object sender, GeoCoordinateChangedEventArgs e)
{
    var topLeft = e.TopLeft;
    var topRight = e.TopRight;
    var bottomLeft = e.BottomLeft;
    var bottomRight = e.BottomRight;
    var center = e.Center;
}

See Also

How to show the current GPS location in Xamarin.Forms SfMaps

How to use Google Maps API to show Google Maps in Xamarin.Forms SfMaps control

How to group the markers based on zoom level in the imagery layer of the SfMaps control

How to add sub shape file layer for ImageryLayer in Xamarin.Forms SfMaps