protected override void OnCreate(Android.OS.Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
AddOnlineBaseLayer(CartoBaseMapStyle.CartoBasemapStylePositron);
// read json from assets and add to map
string json;
using (System.IO.StreamReader sr = new System.IO.StreamReader(Assets.Open("cities15000.geojson")))
{
json = sr.ReadToEnd();
}
// Initialize a local vector data source
LocalVectorDataSource source = new LocalVectorDataSource(BaseProjection);
// Initialize a vector layer with the previous data source
ClusteredVectorLayer layer = new ClusteredVectorLayer(source, new MyClusterElementBuilder(this));
layer.MinimumClusterDistance = 50;
new System.Threading.Thread((obj) =>
{
// Create a basic style, as the ClusterElementBuilder will set the real style
var markerStyleBuilder = new MarkerStyleBuilder();
markerStyleBuilder.Size = 14;
MarkerStyle style = markerStyleBuilder.BuildStyle();
// Read GeoJSON, parse it using SDK GeoJSON parser
GeoJSONGeometryReader reader = new GeoJSONGeometryReader();
// Set target projection to base (mercator)
reader.TargetProjection = BaseProjection;
Alert("Starting load from .geojson");
// Read features from local asset
FeatureCollection features = reader.ReadFeatureCollection(json);
Alert("Finished load from .geojson");
VectorElementVector elements = new VectorElementVector();
for (int i = 0; i < features.FeatureCount; i++)
{
// This data set features point geometry,
// however, it can also be LineGeometry or PolygonGeometry
PointGeometry geometry = (PointGeometry)features.GetFeature(i).Geometry;
elements.Add(new Marker(geometry, style));
}
source.AddAll(elements);
Alert("Clustering started. Please wait...");
// Add the clustered vector layer to the map
MapView.Layers.Add(layer);
}).Start();
}
public override void ViewDidAppear(bool animated)
{
base.ViewDidAppear(animated);
// Add default base layer
AddOnlineBaseLayer(CartoBaseMapStyle.CartoBasemapStylePositron);
// Initialize a local vector data source
LocalVectorDataSource source = new LocalVectorDataSource(BaseProjection);
// Initialize a vector layer with the previous data source
var layer = new ClusteredVectorLayer(source, new MyClusterElementBuilder());
// Default is 100. A good value depends on data
layer.MinimumClusterDistance = 50;
// read json from assets and add to map
string json = System.IO.File.ReadAllText(AssetUtils.CalculateResourcePath("cities15000.geojson"));
// Create a basic style, as the ClusterElementBuilder will set the real style
var markerStyleBuilder = new MarkerStyleBuilder();
markerStyleBuilder.Size = 14;
MarkerStyle style = markerStyleBuilder.BuildStyle();
// Read GeoJSON, parse it using SDK GeoJSON parser
GeoJSONGeometryReader reader = new GeoJSONGeometryReader();
// Set target projection to base (mercator)
reader.TargetProjection = BaseProjection;
// Read features from local asset
FeatureCollection features = reader.ReadFeatureCollection(json);
VectorElementVector elements = new VectorElementVector();
for (int i = 0; i < features.FeatureCount; i++)
{
// This data set features point geometry,
// however, it can also be LineGeometry or PolygonGeometry
PointGeometry geometry = (PointGeometry)features.GetFeature(i).Geometry;
elements.Add(new Marker(geometry, style));
}
// Add the clustered vector layer to the map
source.AddAll(elements);
MapView.Layers.Add(layer);
}
public static void addJosnLayer(IMapView mapView, String json)
{
var features = Newtonsoft.Json.Linq.JObject.Parse(json)["features"];
var geoJsonParser = new GeoJSONGeometryReader();
var proj = new EPSG3857();
var balloonPopupStyleBuilder = new BalloonPopupStyleBuilder();
// Create overlay layer for markers
var dataSource = new LocalVectorDataSource(proj);
var overlayLayer = new ClusteredVectorLayer(dataSource, new MyClusterElementBuilder());
overlayLayer.MinimumClusterDistance = 80; // in pixels
mapView.Layers.Add(overlayLayer);
foreach (var feature in features)
{
var featureType = feature ["type"];
var geometry = feature ["geometry"];
var ntGeom = geoJsonParser.ReadGeometry(Newtonsoft.Json.JsonConvert.SerializeObject(geometry));
var popup = new BalloonPopup(
ntGeom,
balloonPopupStyleBuilder.BuildStyle(),
(string)feature ["properties"]["Capital"], (string)feature ["properties"]["Country"]);
var properties = (JObject)feature ["properties"];
foreach (var property in properties)
{
var key = (string)property.Key;
var value = (string)property.Value;
popup.SetMetaDataElement(key, value);
}
dataSource.Add(popup);
}
}
void LoadData(VectorElementVector elements, MapPos min, MapPos max, float zoom)
{
// Load and parse JSON
string bbox = EncodeBBox(min.X, min.Y, max.X, max.Y);
string unencoded = query.Replace("!bbox!", bbox);
unencoded = unencoded.Replace("zoom('!scale_denominator!')", Convert.ToString(zoom));
// UrlEncode does not replace parentheses by default as they are valid url elements
string encoded = System.Web.HttpUtility.UrlEncode(unencoded).EncodeParenthesis();
string fullPath = baseUrl + "?format=GeoJSON&q=" + encoded;
try
{
string json = GetString(fullPath);
GeoJSONGeometryReader geoJsonParser = new GeoJSONGeometryReader();
FeatureCollection features = geoJsonParser.ReadFeatureCollection(json);
for (int i = 0; i < features.FeatureCount; i++)
{
Geometry geom = features.GetFeature(i).Geometry;
Variant props = features.GetFeature(i).Properties;
// Create object based on given style
VectorElement element;
if (style is PointStyle)
{
element = new Point((PointGeometry)geom, (PointStyle)style);
}
else if (style is MarkerStyle)
{
element = new Marker(geom, (MarkerStyle)style);
}
else if (style is LineStyle)
{
element = new Line((LineGeometry)geom, (LineStyle)style);
}
else if (style is PolygonStyle)
{
element = new Polygon((PolygonGeometry)geom, (PolygonStyle)style);
}
else
{
string text = "Object creation not implemented yet for style: " + style.SwigGetClassNameStyle();
Carto.Utils.Log.Debug(text);
break;
}
// Add all properties as MetaData, so you can use it with click handling
for (int j = 0; j < props.ObjectKeys.Count; j++)
{
var key = props.ObjectKeys[j];
var val = props.GetObjectElement(key);
element.SetMetaDataElement(key, val);
}
elements.Add(element);
}
}
catch (Exception e)
{
Console.WriteLine("Exception: " + e.Message);
}
}