private async void BtnCountFeaturesClick(object sender, RoutedEventArgs e)
{
try
{
// Get the current visible extent.
Geometry currentExtent = MyMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry;
// Create the query parameters.
QueryParameters queryCityCount = new QueryParameters
{
Geometry = currentExtent,
// Specify the interpretation of the Geometry query parameters.
SpatialRelationship = SpatialRelationship.Intersects
};
// Get the count of matching features.
long count = await _featureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI.
ResultsTextbox.Text = $"{count} features in extent";
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString(), "Error");
}
}
private async void BtnCountFeatures_Click(object sender, EventArgs e)
{
try
{
// Get the current visible extent.
Geometry currentExtent = _myMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry;
// Create the query parameters.
QueryParameters queryCityCount = new QueryParameters
{
Geometry = currentExtent,
// Specify the interpretation of the Geometry query parameters.
SpatialRelationship = SpatialRelationship.Intersects
};
// Get the count of matching features.
long count = await _featureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI.
_myResultsLabel.Text = $"{count} features in extent";
}
catch (NullReferenceException exception)
{
// Sample wasn't ready.
System.Diagnostics.Debug.WriteLine(exception);
}
catch (Exception)
{
// Uncaught exception in async void will crash application.
}
}
private async Task FindServiceAreas()
{
try
{
// Create the service area task.
_serviceAreaTask = await ServiceAreaTask.CreateAsync(new Uri(NetworkAnalysisUrl));
// Create the default parameters for the service.
ServiceAreaParameters serviceAreaParameters = await _serviceAreaTask.CreateDefaultParametersAsync();
// Configure the service area parameters.
serviceAreaParameters.PolygonDetail = ServiceAreaPolygonDetail.High;
serviceAreaParameters.ReturnPolygons = true;
serviceAreaParameters.DefaultImpedanceCutoffs.Clear();
serviceAreaParameters.DefaultImpedanceCutoffs.Add(0);
serviceAreaParameters.DefaultImpedanceCutoffs.Add(3);
serviceAreaParameters.DefaultImpedanceCutoffs.Add(5);
// A query that finds all of the relevant facilities from the facilities feature service.
QueryParameters facilityQueryParameters = new QueryParameters();
facilityQueryParameters.WhereClause = "1=1";
// Provide the feature service and the query as parameters to the service area task.
serviceAreaParameters.SetFacilities(_facilitiesTable, facilityQueryParameters);
// Perform the service area analysis.
ServiceAreaResult result = await _serviceAreaTask.SolveServiceAreaAsync(serviceAreaParameters);
// Count the features in the facilities layer.
long facilityCount = await _facilitiesTable.QueryFeatureCountAsync(facilityQueryParameters);
// Get the service area for each facility.
for (int facilityIndex = 0; facilityIndex < facilityCount; facilityIndex++)
{
// Get each area polygon from the result for that facility.
List <ServiceAreaPolygon> areaPolygons = result.GetResultPolygons(facilityIndex).ToList();
// Add each service area polygon to the graphics overlay.
for (int polygonIndex = 0; polygonIndex < areaPolygons.Count; polygonIndex++)
{
// Get the polygon from the result.
Polygon resultingPolygon = areaPolygons[polygonIndex].Geometry;
// Choose a symbol for the polygon.
SimpleFillSymbol selectedSymbol = _fillSymbols[polygonIndex % _fillSymbols.Count];
// Create and add the graphic.
_resultOverlay.Graphics.Add(new Graphic(resultingPolygon, selectedSymbol));
}
}
// Zoom to the extent of the results.
await _myMapView.SetViewpointGeometryAsync(_resultOverlay.Extent, 50);
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex);
ShowMessage("Error", "Couldn't complete service area analysis.");
}
}
private async void CountFeatures_Click(object sender, EventArgs e)
{
// Get the current visible extent.
Geometry currentExtent = _myMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry;
// Create the query parameters.
QueryParameters queryCityCount = new QueryParameters
{
Geometry = currentExtent,
// Specify the interpretation of the Geometry query parameters.
SpatialRelationship = SpatialRelationship.Intersects
};
try
{
// Get the count of matching features.
long count = await _featureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI.
_resultLabel.Text = $"{count} features in extent";
}
catch (Exception ex)
{
new UIAlertView("Error", ex.ToString(), (IUIAlertViewDelegate)null, "OK", null).Show();
}
}
public static async Task <List <object> > GetAttributes(string url, string whereClause = "", string[] fieldNames = null)
{
if (fieldNames == null)
{
return(null);
}
var attributes = new List <object>();
var table = new ServiceFeatureTable(new Uri(url));
await table.LoadAsync();
if (table.GeometryType != Esri.ArcGISRuntime.Geometry.GeometryType.Polygon)
{
return(null);
}
var queryParams = new QueryParameters();
queryParams.WhereClause = whereClause;
var count = await table.QueryFeatureCountAsync(queryParams);
var queryFeatureResults = await table.QueryFeaturesAsync(queryParams);
var resultingFeature = queryFeatureResults.FirstOrDefault();
foreach (var fieldName in fieldNames)
{
attributes.Add(resultingFeature.GetAttributeValue(fieldName));
}
return(attributes);
}
public static async Task <List <Esri.ArcGISRuntime.Geometry.Geometry> > GetGeometries(string url, string whereClause = "objectid > 0")
{
var geometries = new List <Esri.ArcGISRuntime.Geometry.Geometry>();
try
{
var table = new ServiceFeatureTable(new Uri(url));
await table.LoadAsync();
var queryParams = new QueryParameters();
queryParams.WhereClause = whereClause;
var count = await table.QueryFeatureCountAsync(queryParams);
var queryFeatureResults = await table.QueryFeaturesAsync(queryParams);
foreach (var result in queryFeatureResults)
{
geometries.Add(result.Geometry);
}
}
catch (Exception)
{
}
return(geometries);
}
private async void BtnCountFeatures_Click(object sender, EventArgs e)
{
// Get the current visible extent.
Geometry currentExtent = MyMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry;
// Create the query parameters.
QueryParameters queryCityCount = new QueryParameters
{
Geometry = currentExtent,
// Specify the interpretation of the Geometry query parameters.
SpatialRelationship = SpatialRelationship.Intersects
};
try
{
// Get the count of matching features.
long count = await _featureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI.
txtResults.Text = $"{count} features in extent";
}
catch (Exception ex)
{
await Application.Current.MainPage.DisplayAlert("Error", ex.ToString(), "OK");
}
}
private async void BtnCountFeatures_Click(object sender, EventArgs e)
{
// Create the query parameters
QueryParameters queryCityCount = new QueryParameters
{
// Get the current view extent and use that as a query parameters
Geometry = MyMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry,
// Specify the interpretation of the Geometry query parameters
SpatialRelationship = SpatialRelationship.Intersects
};
// Get the count of matching features
long count = await _myFeatureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI
txtResults.Text = $"{count} features in extent";
}
private async void BtnCountFeatures_Click(object sender, EventArgs e)
{
// Get the current visible extent.
Geometry currentExtent = _myMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry;
// Create the query parameters.
QueryParameters queryCityCount = new QueryParameters
{
Geometry = currentExtent,
// Specify the interpretation of the Geometry query parameters.
SpatialRelationship = SpatialRelationship.Intersects
};
// Get the count of matching features.
long count = await _featureTable.QueryFeatureCountAsync(queryCityCount);
// Update the UI.
_resultsLabel.Text = $"{count} features in extent";
}
public static async Task <object> GetAttribute(string url, string whereClause = "", string fieldName = "")
{
var table = new ServiceFeatureTable(new Uri(url));
await table.LoadAsync();
if (table.GeometryType != Esri.ArcGISRuntime.Geometry.GeometryType.Polygon)
{
return(null);
}
var queryParams = new QueryParameters();
queryParams.WhereClause = whereClause;
var count = await table.QueryFeatureCountAsync(queryParams);
var queryFeatureResults = await table.QueryFeaturesAsync(queryParams);
var resultingFeature = queryFeatureResults.FirstOrDefault();
return(resultingFeature.GetAttributeValue(fieldName));
}
