public static Geojson Parse(string text)
{
var node = JSON.Parse(text);
var result = new Geojson();
result.type = node["type"].Value;
result.features = ParseFeatures(node["features"].AsArray);
return(result);
}
public LatLngRect FindCoveringLatLngRect(Geojson json)
{
var lines = json.features
.Where(it => it.geometry.IsLineString())
.Select(it => it.geometry.AsLineString());
var latitudes = lines
.SelectMany(line => line.coordinates.Select(it => it.latitude));
var longitudes = lines
.SelectMany(line => line.coordinates.Select(it => it.longitude));
return(new LatLngRect
{
minLatitude = latitudes.Min(),
maxLatitude = latitudes.Max(),
minLongitude = longitudes.Min(),
maxLongitude = longitudes.Max(),
});
}
void Render(Geojson json)
{
var latLngRect = mapUseCase.FindCoveringLatLngRect(json);
var latLngCenter = latLngRect.getCenter();
var lines = json.features
.Where(it => it.geometry.IsLineString())
.Select(it => it.geometry.AsLineString());
foreach (var line in lines)
{
var from = line.coordinates[0];
var to = line.coordinates[1];
var xyFrom = CoordinateConverter.LatLng2World(latLngCenter, from) * 10;
var xyTo = CoordinateConverter.LatLng2World(latLngCenter, to) * 10;
CreateLine(new[]
{
xyFrom, xyTo
});
}
}
protected override async Task <Geojson> Process(SalvarGeoJsonCommand request, CancellationToken cancellationToken)
{
var repository = _unitOfWork.GetRepository <Geojson>();
var geojson = new Geojson {
FileName = request.FileName, Size = request.Size
};
var geometrias = request
.FeatureCollection
.CleanerFeatureCollection()
.Select(s => FeatureToGeoJson(s));
geojson.AddGeometrias(geometrias.ToList());
await repository.InsertAsync(geojson);
await _unitOfWork.SaveChangesAsync();
return(geojson);
}
private async void Map_OnTap(object sender, TapEventArgs e)
{
Position _position = new Position();
_position = e.Position;
var pin = new Pin
{
Type = PinType.Place,
Position = e.Position,
Label = " Cliked ",
Address = e.Position.Latitude + " X " + e.Position.Latitude,
};
// Get Coordinates Polygon as json string then Deserialize it
var jsonCoordinates = new Geojson().ReadGeoJson(pin);
Polygons = JsonConvert.DeserializeObject <FeatureCollection>(jsonCoordinates);
if (Polygons == null)
{
DependencyService.Get <SnackBar>().ShowSnackBar("There is no detected area");
return;
}
map.Pins.Add(pin);
DrawPolygon();
string result = await DisplayPromptAsync("Info", "if you want to save this area ? enter name it",
"OK", "CANCEL", keyboard : Keyboard.Text);
if (result != null)
{
Models.Polygon polygon = new Models.Polygon();
polygon.PolygonName = result;
polygon.Coordinates = jsonCoordinates;
polygon.Latitude = _position.Latitude;
polygon.Longitude = _position.Longitude;
polygonViewModel.AddPolygon(polygon);
listPolygon.ItemsSource = null;
listPolygon.ItemsSource = polygonViewModel.Polygons;
}
}
