protected override void WriteElementContents(Client.Layer layer)
{
base.WriteElementContents(layer);
HeatMapLayer heatMapLayer = layer as HeatMapLayer;
if (heatMapLayer != null)
{
#region Gradient
if (heatMapLayer.Gradient != null)
{
writer.WriteStartElement(Constants.esriPrefix, "HeatMapLayer.Gradient", Constants.esriNamespace);
writer.WriteStartElement("GradientStopCollection");
foreach (GradientStop gradient in heatMapLayer.Gradient)
{
writer.WriteStartElement("GradientStop");
if (gradient.Color != null)
{
writer.WriteAttributeString("Color", gradient.Color.ToString(CultureInfo.InvariantCulture));
}
if (gradient.Offset != 0)
{
writer.WriteAttributeString("Offset", gradient.Offset.ToString(CultureInfo.InvariantCulture));
}
writer.WriteEndElement();
}
writer.WriteEndElement();
writer.WriteEndElement();
}
#endregion
#region Heat Map Points
if (heatMapLayer.HeatMapPoints != null)
{
writer.WriteStartElement(Constants.esriPrefix, "HeatMapLayer.HeatMapPoints", Constants.esriNamespace);
writer.WriteStartElement(Constants.esriPrefix, "PointCollection", Constants.esriNamespace);
foreach (MapPoint heatMapPoint in heatMapLayer.HeatMapPoints)
{
writer.WriteStartElement(Constants.esriPrefix, "MapPoint", Constants.esriNamespace);
writer.WriteAttributeString("X", heatMapPoint.X.ToString(CultureInfo.InvariantCulture));
writer.WriteAttributeString("Y", heatMapPoint.Y.ToString(CultureInfo.InvariantCulture));
if (heatMapPoint.SpatialReference != null)
{
writer.WriteStartElement(Constants.esriPrefix, "MapPoint.SpatialReference", Constants.esriNamespace);
writeSpatialReference(writer, heatMapPoint.SpatialReference);
writer.WriteEndElement();
}
writer.WriteEndElement();
}
writer.WriteEndElement();
writer.WriteEndElement();
}
#endregion
}
}
protected override void WriteAttributes(Client.Layer layer)
{
base.WriteAttributes(layer);
HeatMapLayer heatMapLayer = layer as HeatMapLayer;
if (heatMapLayer != null)
{
if (heatMapLayer.Intensity != 10.0)
{
writer.WriteAttributeString("Intensity", heatMapLayer.Intensity.ToString(CultureInfo.InvariantCulture));
}
}
}
void Layers_LayersInitialized(object sender, EventArgs args)
{
//Add 1000 random points to the heat map layer
//Replace this with "real" data points that you want to display
//in the heat map.
HeatMapLayer layer = MyMap.Layers["RandomHeatMapLayer"] as HeatMapLayer;
Random rand = new Random();
for (int i = 0; i < 1000; i++)
{
double x = rand.NextDouble() * MyMap.Extent.Width - MyMap.Extent.Width / 2;
double y = rand.NextDouble() * MyMap.Extent.Height - MyMap.Extent.Height / 2;
layer.HeatMapPoints.Add(new ESRI.ArcGIS.Client.Geometry.MapPoint(x, y));
}
}
protected override void CreateHeatMapIfNeeded()
{
if (_heatMapLayer == null)
{
_heatMapLayer = new HeatMapLayer(Xamarin.Forms.Forms.Context, FormsMap)
{
ParentMap = _googleMap,
Radius = FormsMap.Radius,
Intensity = FormsMap.Intensity,
Locations = FormsMap.Locations?.Select(CoordinateConverter.ConvertToNative)
};
FormsMap.PropertyChanged -= FormsMapPropertyChanged;
FormsMap.PropertyChanged += FormsMapPropertyChanged;
_nativeMap.AddView(_heatMapLayer);
}
}
public MainPage()
{
this.InitializeComponent();
this.Loaded += (s, e) =>
{
testData = new LocationCollection();
layer = new HeatMapLayer()
{
ParentMap = MyMap,
Locations = GetTestData(500),
Radius = 250000
};
MyMap.Children.Add(layer);
};
}
protected override void CreateHeatMapIfNeeded()
{
if (_heatMapLayer == null)
{
_heatMapLayer = new HeatMapLayer(FormsMap)
{
ParentMap = _nativeMap,
Radius = FormsMap.Radius,
Intensity = FormsMap.Intensity,
Locations = FormsMap.Locations?.Select(CoordinateConverter.ConvertToNative)
};
FormsMap.PropertyChanged -= FormsMapPropertyChanged;
FormsMap.PropertyChanged += FormsMapPropertyChanged;
_heatMapLayer.Frame = new CoreGraphics.CGRect(0, 0, _nativeMap.Frame.Width, _nativeMap.Frame.Height);
_nativeMap.AddSubview(_heatMapLayer);
}
}
protected override void CreateHeatMapIfNeeded()
{
if (_heatMapLayer == null)
{
IEnumerable <BasicGeoposition> positions = FormsMap.Locations?.Select(pos => new BasicGeoposition
{
Latitude = pos.Latitude,
Longitude = pos.Longitude
});
Geopath polygonPath = new Geopath(positions);
_heatMapLayer = new HeatMapLayer(FormsMap)
{
ParentMap = _nativeMap,
Locations = polygonPath,
Radius = FormsMap.Radius,
Intensity = FormsMap.Intensity,
Visibility = Visibility.Collapsed
};
_nativeMap.Children.Add(_heatMapLayer);
}
}
/// <summary>
/// Handles click event on search button and handles search functionality
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private async void Search_Click(object sender, RoutedEventArgs e)
{
if (EndDatePicker.SelectedDate != null && StartDatePicker.SelectedDate != null)
{
//Clear prior search
myMap.Visibility = Visibility.Hidden;
myMapLabel.Visibility = Visibility.Collapsed;
myMap.Children.Clear();
SearchResults.Visibility = Visibility.Collapsed;
AddressList.Children.Clear();
ErrorMessage.Visibility = Visibility.Collapsed;
LoadingLabel.Visibility = Visibility.Visible;
LocationData locationData = locationApi.getLocationData(LocationBox.Text);
myMap.Center = locationData.CentrePoint;
ComboBoxItem crimetype = (ComboBoxItem)CrimeType.SelectedItem;
string crimeTag = (String)crimetype.Tag;
DateTime startDate = (DateTime)StartDatePicker.SelectedDate;
DateTime endDate = (DateTime)EndDatePicker.SelectedDate;
List <Location> locations = new List <Location>();
try
{
locations = await policeApi.getCrimeLocations(locationData, startDate, endDate, crimeTag);
LocationCollection locationCollection = new LocationCollection();
// create List of locations to add to heat map layer
foreach (Location location in locations)
{
locationCollection.Add(location);
}
// Create new HeatMapLayer setting view properties
layer = new HeatMapLayer()
{
ParentMap = myMap,
Locations = locationCollection,
Radius = 500,
Opacity = 0.5
};
// Add to map view as child component layer
myMap.Children.Add(layer);
LocationRect box = new LocationRect(locations);
myMap.SetView(box);
}
catch (Exception ex)
{
MessageBox.Show("--Error retrieving data from server--\n" +
"Please try one or more of the following: \n" +
"* Ensuring your are entering a valid geolocation in England and Wales (e.g avoid any special characters)\n" +
"* Narrowing the search area (e.g South London/Chelsea instead of London \n" +
"* Reducing the date range \n" +
"* Searching for less common crimes (e.g bicycle crime instead of public order offences)\n\n"
,
"Error", MessageBoxButton.OK);
Debug.WriteLine(ex.StackTrace);
InitializeComponent();
}
LoadingLabel.Visibility = Visibility.Hidden;
myMap.Visibility = Visibility.Visible;
myMap.Focus(); //allows '+' and '-' to zoom the map
}
else
{
MessageBox.Show("Please enter a start and end date", "Enter date", MessageBoxButton.OK);
}
}
