// Handle the selection event for the picker.
public override void Selected(UIPickerView pickerView, nint row, nint component)
{
// Get the selected datum transformation factor.
_selectedTransformation = _datumTransformations[(int)pickerView.SelectedRowInComponent(0)];
// Raise the selection event (with the new transformation) so listeners can handle it.
EventHandler <TransformationSelectionEventArgs> selectionEventHandler = TransformationSelected;
if (selectionEventHandler != null)
{
TransformationSelectionEventArgs args = new TransformationSelectionEventArgs(_selectedTransformation);
selectionEventHandler(this, args);
}
}
// Handle selection events in the transformation picker.
private void TransformationsPicker_TransformationSelected(object sender, TransformationSelectionEventArgs e)
{
// Get the selected transform from the event arguments. Return if none is selected.
DatumTransformation selectedTransform = e.Transformation;
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;
}
}
}