// On tap, get an input line and perform a buffer and clip operation
private void mapView1_Tap(object sender, MapViewInputEventArgs e)
{
if (!m_firstPointAdded)
{
m_firstPointAdded = true;
// Clear previous results
ClipLines.Clear();
ClippedCounties.Clear();
if (m_clippedCountiesLayer != null)
{
Layers.Remove(m_clippedCountiesLayer);
m_clippedCountiesLayer = null;
}
// Show instructions
StatusText = "Tap to add a point to the line. Double-tap to finish.";
StatusVisibility = Visibility.Visible;
}
else if (BusyVisibility == Visibility.Visible)
{
MessageBox.Show("Please wait until the current operation is complete.");
return;
}
}
// Waits for the user to draw a line, then performs the buffer and clip operation
private async void getInputLineAndClip()
{
if (m_firstPointAdded)
{
return;
}
// Get line from user
var clipLine = await Editor.RequestShapeAsync(DrawShape.Polyline,
new SimpleLineSymbol()
{
Color = Colors.Red, Width = 2, Style = SimpleLineStyle.Dash
});
ClipLines.Add(new Graphic()
{
Geometry = clipLine
});
// Show busy UI
BusyVisibility = Visibility.Visible;
StatusText = "Executing...";
string error = null;
// Initialize the Geoprocessing task with the buffer and clip service endpoint
Geoprocessor task = new Geoprocessor(new Uri("http://serverapps10.esri.com/ArcGIS/rest/services/SamplesNET/" +
"USA_Data_ClipTools/GPServer/ClipCounties"));
// Initialize input parameters
var parameter = new GPInputParameter()
{
OutSpatialReference = SpatialReferences.WebMercator
};
parameter.GPParameters.Add(new GPFeatureRecordSetLayer("Input_Features", clipLine)); // input geometry
parameter.GPParameters.Add(new GPLinearUnit("Linear_unit", LinearUnits.Miles, BufferDistance)); // buffer distance
try
{
// Submit the job and await the results
var result = await task.SubmitJobAsync(parameter);
// Poll the server every two seconds for the status of the job.
while (result.JobStatus != GPJobStatus.Cancelled &&
result.JobStatus != GPJobStatus.Deleted &&
result.JobStatus != GPJobStatus.Failed &&
result.JobStatus != GPJobStatus.Succeeded &&
result.JobStatus != GPJobStatus.TimedOut)
{
result = await task.CheckJobStatusAsync(result.JobID);
// show the status
var descriptions = result.Messages.Select(msg => msg.Description);
var status = string.Join(Environment.NewLine, descriptions);
if (!string.IsNullOrEmpty(status))
{
StatusText = status;
}
await Task.Delay(2000);
}
if (result.JobStatus == GPJobStatus.Succeeded)
{
// Get the results
var resultData = await task.GetResultDataAsync(result.JobID, "Clipped_Counties");
if (resultData is GPFeatureRecordSetLayer)
{
GPFeatureRecordSetLayer resultsLayer = resultData as GPFeatureRecordSetLayer;
if (resultsLayer.FeatureSet != null &&
resultsLayer.FeatureSet.Features != null &&
resultsLayer.FeatureSet.Features.Count != 0)
{
// Results were returned as graphics. Add them to the ClippedCounties collection
ClippedCounties = new ObservableCollection <Graphic>(resultsLayer.FeatureSet.Features);
}
else // Try to get results as a GPResultImageLayer
{
StatusText = "Clip operation complete. Retrieving results...";
m_clippedCountiesLayer = await task.GetResultImageLayerAsync(result.JobID, "Clipped_Counties");
// If successful, add the layer to the layers collection
if (m_clippedCountiesLayer != null)
{
m_clippedCountiesLayer.Opacity = 0.5;
// Insert the layer below the input layer
Layers.Insert(Layers.IndexOf(m_clipLinesLayer), m_clippedCountiesLayer);
// Wait until the result layer is initialized
await m_clippedCountiesLayer.InitializeAsync();
}
else
{
error = "No results found";
}
}
}
else
{
error = "Clip operation failed";
}
}
else
{
error = "Clip operation failed";
}
}
catch (Exception ex)
{
error = "Clip operation failed: " + ex.Message;
}
// If operation did not succeed, notify user
if (error != null)
{
MessageBox.Show(error);
}
// Hide busy UI
BusyVisibility = StatusVisibility = Visibility.Collapsed;
StatusText = "";
m_firstPointAdded = false;
getInputLineAndClip();
}
