// Function to get suitable datum transformations for the specified input and output spatial references.
private void GetSuitableTransformations(SpatialReference inSpatialRef, SpatialReference outSpatialRef, bool considerExtent)
{
// Get suitable transformations. Use the current extent to evaluate suitability, if requested.
IReadOnlyList <DatumTransformation> transformations;
if (considerExtent)
{
Envelope currentExtent = _myMapView.GetCurrentViewpoint(ViewpointType.BoundingGeometry).TargetGeometry as Envelope;
transformations = TransformationCatalog.GetTransformationsBySuitability(inSpatialRef, outSpatialRef, currentExtent);
}
else
{
transformations = TransformationCatalog.GetTransformationsBySuitability(inSpatialRef, outSpatialRef);
}
// Get the default transformation for the specified input and output spatial reference.
DatumTransformation defaultTransform = TransformationCatalog.GetTransformation(inSpatialRef, outSpatialRef);
// Create a list of transformations.
List <DatumTransformation> transformsList = new List <DatumTransformation>();
foreach (DatumTransformation transformation in transformations)
{
transformsList.Add(transformation);
}
// Create an adapter for showing the spinner list.
TransformationsAdapter transformationsAdapter = new TransformationsAdapter(this, transformsList);
transformationsAdapter.DefaultTransformation = defaultTransform;
// Apply the adapter to the spinner.
_transformationsPicker.Adapter = transformationsAdapter;
}
private void TransformationsPicker_ItemSelected(object sender, AdapterView.ItemSelectedEventArgs e)
{
// Get the selected transform from the spinner. Return if none is selected.
TransformationsAdapter adapter = _transformationsPicker.Adapter as TransformationsAdapter;
DatumTransformation selectedTransform = adapter[e.Position];
if (selectedTransform == null)
{
return;
}
try
{
// Project the original point using the selected transform.
MapPoint projectedPoint = (MapPoint)GeometryEngine.Project(_originalPoint, _myMapView.SpatialReference, selectedTransform);
// Update the projected graphic (if it already exists), create it otherwise.
if (_projectedPointGraphic != null)
{
_projectedPointGraphic.Geometry = projectedPoint;
}
else
{
// Create a symbol to represent the projected point (a cross to ensure both markers are visible).
SimpleMarkerSymbol projectedPointMarker = new SimpleMarkerSymbol(SimpleMarkerSymbolStyle.Cross, Color.Red, 15);
// Create the point graphic and add it to the overlay.
_projectedPointGraphic = new Graphic(projectedPoint, projectedPointMarker);
_pointsOverlay.Graphics.Add(_projectedPointGraphic);
}
_messagesTextView.Text = "Projected point using transform: " + selectedTransform.Name;
}
catch (ArcGISRuntimeException ex)
{
// Exception if a transformation is missing grid files.
_messagesTextView.Text = "Error using selected transformation: " + ex.Message;
// Remove the projected point graphic (if it exists).
if (_projectedPointGraphic != null && _pointsOverlay.Graphics.Contains(_projectedPointGraphic))
{
_pointsOverlay.Graphics.Remove(_projectedPointGraphic);
_projectedPointGraphic = null;
}
}
}