// Raised when the locator search completes
private void AddressToLocationsCompleted(object sender, AddressToLocationsEventArgs args)
{
if (args.Results == null || args.Results.Count < 1) // No results found
{
IsSearching = false; // Reset busy state
OnSearchCompleted(); // Raise completed event
return;
}
// check that coordinates returned by extent fields are valid
AddressCandidate result = args.Results[0];
double xMin, xMax, yMin, yMax;
bool useExtentFields = UseExtentFields;
if (UseExtentFields && getExtentFields(result, out xMin, out yMin, out xMax, out yMax))
{
if (xMax <= xMin || yMax <= yMin)
{
// Extent fields are returning invalid coordinates. Disable use of extent fields.
useExtentFields = false;
}
}
// Check whether result extents will need to be reprojected using a geometry service
SpatialReference locatorSRef = LocatorInfo.SpatialReference;
bool needsGeometryServiceProjection = (useExtentFields &&
((locatorSRef != null && !locatorSRef.IsWebMercator() && !locatorSRef.IsGeographic())
|| (!_map.SpatialReference.IsWebMercator() && !_map.SpatialReference.IsGeographic())))
|| (!useExtentFields && _mapUnits == LengthUnits.UnitsDecimalDegrees);
List<Graphic> graphicsToProject = new List<Graphic>();
List<LocatorResultViewModel> geographicResults = new List<LocatorResultViewModel>();
foreach (AddressCandidate candidate in args.Results)
{
// Create the result ViewModel from the result returned from the service
LocatorResultViewModel resultViewModel = new LocatorResultViewModel(candidate);
// If extent fields are being used, initialize the extent on the service
if (useExtentFields && getExtentFields(candidate, out xMin, out yMin, out xMax, out yMax))
{
Envelope extent = new Envelope(xMin, yMin, xMax, yMax);
if (LocatorInfo.SpatialReference != null)
{
extent.SpatialReference = locatorSRef;
if (!needsGeometryServiceProjection)
{
// No geometry service needed, so set extent directly
if (locatorSRef.IsWebMercator() && _map.SpatialReference.WKID == 4326)
extent = (new WebMercator()).ToGeographic(extent) as Envelope;
else if (locatorSRef.WKID == 4326 && _map.SpatialReference.IsWebMercator())
extent = (new WebMercator()).FromGeographic(extent) as Envelope;
resultViewModel.Extent = extent;
}
else
{
// Since results need to be reprojected, add them to collection to be projected
// once they've all been gone through
graphicsToProject.Add(new Graphic() { Geometry = extent });
_queuedResults.Enqueue(resultViewModel);
}
}
else
{
resultViewModel.Extent = extent;
}
}
if (resultViewModel.Extent == null && !useExtentFields)
{
// Initialize the result extent based on the specified extent width
if (_gotMapUnits) // check whether map units have been retrieved for the current search
{
if (!needsGeometryServiceProjection)
{
initializeResultExtent(resultViewModel);
_results.Add(resultViewModel);
}
else if (_mapUnits != LengthUnits.UnitsDecimalDegrees)
{
initializeResultExtent(resultViewModel);
graphicsToProject.Add(new Graphic() { Geometry = resultViewModel.Extent });
_queuedResults.Enqueue(resultViewModel);
}
else
{
// results in a geographic coordinate system (units of decimal degrees) require
// special handling because an envelope around the result cannot be calculated
// in the result's spatial reference.
geographicResults.Add(resultViewModel);
}
}
else
{
// map units are not yet known, so queue up the result to be added after map units are
// determined.
_queuedResults.Enqueue(resultViewModel);
}
}
else if (!needsGeometryServiceProjection)
{
// No projection needed, so the result can be added now
_results.Add(resultViewModel);
}
}
if (!needsGeometryServiceProjection) // Check whether result extents need to be reprojected
{
// No projection needed, so the operation is complete.
// Refresh paged collection to update pagination
PagedResults.Refresh();
IsSearching = false; // Reset busy state
OnSearchCompleted(); // Raise completed event
}
else if (graphicsToProject.Count > 0)
{
// result extents need to be reprojected
if (_geometryService == null)
{
_geometryService = new GeometryService(GeometryServiceUrl);
_geometryService.ProjectCompleted += GeometryService_ProjectCompleted;
}
_geometryService.ProjectAsync(graphicsToProject, _map.SpatialReference, _queuedResults);
}
else
{
// result extents need to be created in a spatial reference that uses linear units (i.e.
// projected coordinate system), then projected back into the current spatial reference.
handleGeographicResults(geographicResults);
}
}
// Initializes the extent of a locator result based on the specified result extent width
private void initializeResultExtent(LocatorResultViewModel result)
{
double extentHeight = _extentWidthInMapUnits / 3;
result.Extent = result.Candidate.Location.ToEnvelope(_extentWidthInMapUnits, extentHeight);
}