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// Copyright 2018 Esri.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
// language governing permissions and limitations under the License.
using Android.App;
using Android.OS;
using Android.Widget;
using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Symbology;
using Esri.ArcGISRuntime.Tasks.NetworkAnalysis;
using Esri.ArcGISRuntime.UI;
using Esri.ArcGISRuntime.UI.Controls;
using System;
using System.Collections.Generic;
using System.Linq;
namespace ArcGISRuntime.Samples.ClosestFacility
{
[Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
[ArcGISRuntime.Samples.Shared.Attributes.Sample(
name: "Find closest facility to an incident (interactive)",
category: "Network analysis",
description: "Find a route to the closest facility from a location.",
instructions: "Tap near any of the hospitals and a route will be displayed from that clicked location to the nearest hospital.",
tags: new[] { "incident", "network analysis", "route", "search" })]
public class ClosestFacility : Activity
{
// Hold a reference to the map view.
private MapView _myMapView;
// Holds locations of hospitals around San Diego.
private List<Facility> _facilities;
// Graphics overlays for facilities and incidents.
private GraphicsOverlay _facilityGraphicsOverlay;
// Symbol for facilities.
private PictureMarkerSymbol _facilitySymbol;
// Overlay for the incident.
private GraphicsOverlay _incidentGraphicsOverlay;
// Black cross where user clicked.
private MapPoint _incidentPoint;
// Symbol for the incident.
private SimpleMarkerSymbol _incidentSymbol;
// Used to display route between incident and facility to mapview.
private SimpleLineSymbol _routeSymbol;
// Solves task to find closest route between an incident and a facility.
private ClosestFacilityTask _task;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
Title = "Closest facility";
// Create the UI
CreateLayout();
// Initialize the app
Initialize();
}
private void CreateLayout()
{
// Create a new layout for the entire page
LinearLayout layout = new LinearLayout(this) { Orientation = Orientation.Vertical };
// Create a TextView for instructions.
TextView sampleInstructionsTextView = new TextView(this)
{
Text = "Tap to find the route to the nearest hospital to your incident."
};
layout.AddView(sampleInstructionsTextView);
// Add the map view to the layout
_myMapView = new MapView(this);
layout.AddView(_myMapView);
// Show the layout in the app
SetContentView(layout);
}
private async void Initialize()
{
// Hook up the DrawStatusChanged event.
_myMapView.DrawStatusChanged += OnDrawStatusChanged;
// Construct the map and set the MapView.Map property.
Map map = new Map(BasemapStyle.ArcGISLightGray);
_myMapView.Map = map;
// Create a ClosestFacilityTask using the San Diego Uri.
_task = await ClosestFacilityTask.CreateAsync(new Uri("https://sampleserver6.arcgisonline.com/arcgis/rest/services/NetworkAnalysis/SanDiego/NAServer/ClosestFacility"));
// List of facilities to be placed around San Diego area.
_facilities = new List<Facility> {
new Facility(new MapPoint(-1.3042129900625112E7, 3860127.9479775648, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3042193400557665E7, 3862448.873041752, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3046882875518233E7, 3862704.9896770366, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3040539754780494E7, 3862924.5938606677, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3042571225655518E7, 3858981.773018156, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3039784633928463E7, 3856692.5980474586, SpatialReferences.WebMercator)),
new Facility(new MapPoint(-1.3049023883956768E7, 3861993.789732541, SpatialReferences.WebMercator))
};
// Center the map on the San Diego facilities.
Envelope fullExtent = GeometryEngine.CombineExtents(_facilities.Select(facility => facility.Geometry));
await _myMapView.SetViewpointGeometryAsync(fullExtent, 50);
// Create a symbol for displaying facilities.
_facilitySymbol = new PictureMarkerSymbol(new Uri("https://static.arcgis.com/images/Symbols/SafetyHealth/Hospital.png"))
{
Height = 30,
Width = 30
};
// Incident symbol.
_incidentSymbol = new SimpleMarkerSymbol(SimpleMarkerSymbolStyle.Cross, System.Drawing.Color.FromArgb(255, 0, 0, 0), 30);
// Route to hospital symbol.
_routeSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Solid, System.Drawing.Color.FromArgb(255, 0, 0, 255), 5.0f);
// Create Graphics Overlays for incidents and facilities.
_incidentGraphicsOverlay = new GraphicsOverlay();
_facilityGraphicsOverlay = new GraphicsOverlay();
// Create a graphic and add to graphics overlay for each facility.
foreach (Facility facility in _facilities)
{
_facilityGraphicsOverlay.Graphics.Add(new Graphic(facility.Geometry, _facilitySymbol));
}
// Add each graphics overlay to MyMapView.
_myMapView.GraphicsOverlays.Add(_incidentGraphicsOverlay);
_myMapView.GraphicsOverlays.Add(_facilityGraphicsOverlay);
}
private void OnDrawStatusChanged(object sender, DrawStatusChangedEventArgs e)
{
if (e.Status == DrawStatus.Completed)
{
// Link the action of tapping on the map with the MyMapView_GeoViewTapped method.
_myMapView.GeoViewTapped += MyMapView_GeoViewTapped;
// Remove this method from DrawStatusChanged events.
_myMapView.DrawStatusChanged -= OnDrawStatusChanged;
}
}
private void MyMapView_GeoViewTapped(object sender, Esri.ArcGISRuntime.UI.Controls.GeoViewInputEventArgs e)
{
// Clear any prior incident and routes from the graphics.
_incidentGraphicsOverlay.Graphics.Clear();
// Get the tapped point.
_incidentPoint = e.Location;
// Populate the facility parameters than solve using the task.
PopulateParametersAndSolveRouteAsync();
}
private async void PopulateParametersAndSolveRouteAsync()
{
try
{
// Set facilities and incident in parameters.
ClosestFacilityParameters closestFacilityParameters = await _task.CreateDefaultParametersAsync();
closestFacilityParameters.SetFacilities(_facilities);
closestFacilityParameters.SetIncidents(new List<Incident> { new Incident(_incidentPoint) });
// Use the task to solve for the closest facility.
ClosestFacilityResult result = await _task.SolveClosestFacilityAsync(closestFacilityParameters);
// Get the index of the closest facility to incident. (0) is the index of the incident, [0] is the index of the closest facility.
int closestFacility = result.GetRankedFacilityIndexes(0)[0];
// Get route from closest facility to the incident and display to mapview.
ClosestFacilityRoute route = result.GetRoute(closestFacility, 0);
// Add graphics for the incident and route.
_incidentGraphicsOverlay.Graphics.Add(new Graphic(_incidentPoint, _incidentSymbol));
_incidentGraphicsOverlay.Graphics.Add(new Graphic(route.RouteGeometry, _routeSymbol));
}
catch (Esri.ArcGISRuntime.Http.ArcGISWebException exception)
{
if (exception.Message.Equals("Unable to complete operation."))
{
CreateErrorDialog("Incident not within San Diego area!");
}
else
{
CreateErrorDialog("An ArcGIS web exception occurred. \n" + exception.Message);
}
}
}
private void CreateErrorDialog(string message)
{
// Create a dialog to show message to user.
AlertDialog alert = new AlertDialog.Builder(this).Create();
alert.SetMessage(message);
alert.Show();
}
}
}