Identify

This sample demonstrates using the ArcGIS Runtime SDK for WPF to perform identify operations on local data. To use the sample, simply click anywhere in the United States to identify features. The results will be shown in the drop-down menu and DataGrid in the upper right corner of the application. View the data for different results by selecting them from the drop-down menu.

In the code-behind, a LocalMapService is started and the Url property is used to create an IdentifyTask to perform the identify operation. The tasks IdentifyParameters are specified to query the geometry of the map click and to query all the layers in the local map service, which enables the returning of results from multiple layers.

XAML

<UserControl x:Class="ArcGISWPFSDK.LocalIdentify"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009">
    <Grid x:Name="LayoutRoot" Background="White" >
        <Grid.Resources>
            <BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
            <esri:SimpleRenderer x:Key="MySimplePolygonRenderer">
                <esri:SimpleRenderer.Symbol>
                    <esri:SimpleFillSymbol Fill="#440000FF"/>
                </esri:SimpleRenderer.Symbol>
            </esri:SimpleRenderer>
            <esri:PictureMarkerSymbol x:Key="DefaultPictureSymbol" OffsetX="35" OffsetY="35" 
                 Source="/Assets/Images/i_about.png" />
            <LinearGradientBrush x:Key="PanelGradient" EndPoint="0.5,1" StartPoint="0.5,0">
                <LinearGradientBrush.RelativeTransform>
                    <TransformGroup>
                        <ScaleTransform CenterY="0.5" CenterX="0.5"/>
                        <SkewTransform CenterY="0.5" CenterX="0.5"/>
                        <RotateTransform Angle="176" CenterY="0.5" CenterX="0.5"/>
                        <TranslateTransform/>
                    </TransformGroup>
                </LinearGradientBrush.RelativeTransform>
                <GradientStop Color="#FF145787" Offset="0.16"/>
                <GradientStop Color="#FF3D7FAC" Offset="0.502"/>
                <GradientStop Color="#FF88C5EF" Offset="0.984"/>
            </LinearGradientBrush>
        </Grid.Resources>
        <esri:Map x:Name="MyMap" MinimumResolution="2445.98490512499" Extent="-15000000,2000000,-7000000,8000000" Background="#FFE3E3E3" MouseClick="QueryPoint_MouseClick" IsEnabled="False" >
            <esri:ArcGISLocalTiledLayer ID="BaseMap" Path="..\\Data\\TPKs\\Topographic.tpk"/>
            <esri:ArcGISLocalDynamicMapServiceLayer Path="..\\Data\\MPKS\\USCitiesStates.mpk"/>
            <esri:GraphicsLayer ID="MyGraphicsLayer" />
        </esri:Map>
        <Grid x:Name="IdentifyGrid" HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,7,7,0" >
            <Rectangle Fill="{StaticResource PanelGradient}" Stroke="Gray" Margin="-5,1,-2,-6" RadiusX="10" RadiusY="10">
                <Rectangle.Effect>
                    <DropShadowEffect/>
                </Rectangle.Effect>
            </Rectangle>
            <TextBlock x:Name="DataDisplayTitleTop" Text="Click on map to identify a feature" Foreground="White" FontSize="12" 
                      Margin="2,8,8,-3" />
            <StackPanel x:Name="IdentifyResultsPanel" Orientation="Vertical" Margin="15" HorizontalAlignment="Center" 
                            VerticalAlignment="Top" Visibility="Collapsed" >
                <ComboBox x:Name="IdentifyComboBox" MinWidth="150" SelectionChanged="cb_SelectionChanged"
                         Margin="2,10,2,2" >
                </ComboBox>
                <ScrollViewer HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Auto"  
                         Width="230" MaxHeight="340">
                    <DataGrid x:Name="IdentifyDetailsDataGrid" AutoGenerateColumns="False" HeadersVisibility="None" 
                              Background="White">
                        <DataGrid.Columns>
                            <DataGridTextColumn Width="95" Binding="{Binding Path=Key}" FontWeight="Bold" IsReadOnly="True"/>
                            <DataGridTextColumn Width="115" Binding="{Binding Path=Value}" IsReadOnly="True"/>
                        </DataGrid.Columns>
                    </DataGrid>
                </ScrollViewer>
            </StackPanel>
        </Grid>
        <ProgressBar x:Name="MyProgressBar" IsIndeterminate="True" VerticalAlignment="Bottom" Width="200" Height="20" Margin="10" Visibility="{Binding Path=IsBusy, Converter={StaticResource BooleanToVisibilityConverter}}"></ProgressBar>
    </Grid>
</UserControl>

C#

using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;
using ESRI.ArcGIS.Client;
using ESRI.ArcGIS.Client.Tasks;
using ESRI.ArcGIS.Client.Local;
using System.ComponentModel;

namespace ArcGISWPFSDK
{
    public partial class LocalIdentify : UserControl, INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        private bool _isBusy = true;

        public bool IsBusy
        {
            get
            {
                return _isBusy;
            }
            set
            {
                _isBusy = value;

                if (PropertyChanged != null)
                {

                    PropertyChanged(this, new PropertyChangedEventArgs("IsBusy"));
                }
            }
        }  
        private List<DataItem> _dataItems = null;
        ESRI.ArcGIS.Client.Geometry.MapPoint _clickPoint;
        LocalMapService _mapService;

        public LocalIdentify()
        {
            InitializeComponent();

            LocalMapService.GetServiceAsync("..\\Data\\MPKS\\USCitiesStates.mpk", (localMapService) =>
            {
                _mapService = localMapService;
                MyMap.IsEnabled = true;
                DataContext = this;
                IsBusy = false;
            });
        }
        private void QueryPoint_MouseClick(object sender, ESRI.ArcGIS.Client.Map.MouseEventArgs e)
        {
            _clickPoint = e.MapPoint;

            ESRI.ArcGIS.Client.Tasks.IdentifyParameters identifyParams = new IdentifyParameters()
            {
                Geometry = _clickPoint,
                MapExtent = MyMap.Extent,
                Width = (int)MyMap.ActualWidth,
                Height = (int)MyMap.ActualHeight,
                LayerOption = LayerOption.visible

            };
            IdentifyTask identifyTask = new IdentifyTask();
            identifyTask.Url = _mapService.UrlMapService;
            identifyTask.ExecuteCompleted += IdentifyTask_ExecuteCompleted;
            identifyTask.Failed += IdentifyTask_Failed;
            identifyTask.ExecuteAsync(identifyParams);
            GraphicsLayer graphicsLayer = MyMap.Layers["MyGraphicsLayer"] as GraphicsLayer;
            graphicsLayer.ClearGraphics();
            ESRI.ArcGIS.Client.Graphic graphic = new ESRI.ArcGIS.Client.Graphic()
            {
                Geometry = _clickPoint,
                Symbol = LayoutRoot.Resources["DefaultPictureSymbol"] as ESRI.ArcGIS.Client.Symbols.Symbol
            };
            graphicsLayer.Graphics.Add(graphic);
        }

        public void ShowFeatures(List<IdentifyResult> results)
        {
            _dataItems = new List<DataItem>();

            if (results != null && results.Count > 0)
            {
                IdentifyComboBox.Items.Clear();
                foreach (IdentifyResult result in results)
                {
                    Graphic feature = result.Feature;
                    string title = result.Value.ToString() + " (" + result.LayerName + ")";
                    _dataItems.Add(new DataItem()
                    {
                        Title = title,
                        Data = feature.Attributes
                    });
                    IdentifyComboBox.Items.Add(title);
                }

                IdentifyComboBox.UpdateLayout();
                IdentifyComboBox.SelectedIndex = 0;
            }
        }

        void cb_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            int index = IdentifyComboBox.SelectedIndex;
            if (index > -1)
                IdentifyDetailsDataGrid.ItemsSource = _dataItems[index].Data;
        }

        private void IdentifyTask_ExecuteCompleted(object sender, IdentifyEventArgs args)
        {
            IdentifyDetailsDataGrid.ItemsSource = null;

            if (args.IdentifyResults != null && args.IdentifyResults.Count > 0)
            {
                IdentifyResultsPanel.Visibility = Visibility.Visible;

                ShowFeatures(args.IdentifyResults);
            }
            else
            {
                IdentifyComboBox.Items.Clear();
                IdentifyComboBox.UpdateLayout();

                IdentifyResultsPanel.Visibility = Visibility.Collapsed;
            }
        }

        public class DataItem
        {
            public string Title { get; set; }
            public IDictionary<string, object> Data { get; set; }
        }

        void IdentifyTask_Failed(object sender, TaskFailedEventArgs e)
        {
            MessageBox.Show("Identify failed. Error: " + e.Error);
        }
    }
}

VB.NET

Imports System.Collections.Generic
Imports System.Windows
Imports System.Windows.Controls
Imports ESRI.ArcGIS.Client
Imports ESRI.ArcGIS.Client.Tasks
Imports ESRI.ArcGIS.Client.Local
Imports System.ComponentModel

Namespace ArcGISWPFSDK
    Partial Public Class LocalIdentify
        Inherits UserControl
        Implements INotifyPropertyChanged
        Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged
        Private _isBusy As Boolean = True
        Public Property IsBusy() As Boolean
            Get
                Return _isBusy
            End Get
            Set(value As Boolean)
                _isBusy = value

                RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs("IsBusy"))
            End Set
        End Property
        Private _dataItems As List(Of DataItem) = Nothing
        Private _clickPoint As ESRI.ArcGIS.Client.Geometry.MapPoint
        Private _mapService As LocalMapService

        Public Sub New()
            InitializeComponent()

            LocalMapService.GetServiceAsync("..\Data\MPKS\USCitiesStates.mpk", Function(localMapService__1)
                                                                                   _mapService = localMapService__1
                                                                                   MyMap.IsEnabled = True
                                                                                   DataContext = Me
                                                                                   IsBusy = False
                                                                               End Function)
        End Sub
        Private Sub QueryPoint_MouseClick(sender As Object, e As ESRI.ArcGIS.Client.Map.MouseEventArgs)
            _clickPoint = e.MapPoint


            Dim identifyParams As ESRI.ArcGIS.Client.Tasks.IdentifyParameters = New IdentifyParameters() With { _
             .Geometry = _clickPoint, _
             .MapExtent = MyMap.Extent, _
             .Width = CInt(Math.Truncate(MyMap.ActualWidth)), _
             .Height = CInt(Math.Truncate(MyMap.ActualHeight)), _
             .LayerOption = LayerOption.visible _
            }
            Dim identifyTask As New IdentifyTask()
            identifyTask.Url = _mapService.UrlMapService
            AddHandler identifyTask.ExecuteCompleted, AddressOf IdentifyTask_ExecuteCompleted
            AddHandler identifyTask.Failed, AddressOf IdentifyTask_Failed
            identifyTask.ExecuteAsync(identifyParams)
            Dim graphicsLayer As GraphicsLayer = TryCast(MyMap.Layers("MyGraphicsLayer"), GraphicsLayer)
            graphicsLayer.ClearGraphics()
            Dim graphic As New ESRI.ArcGIS.Client.Graphic() With { _
             .Geometry = _clickPoint, _
             .Symbol = TryCast(LayoutRoot.Resources("DefaultPictureSymbol"), ESRI.ArcGIS.Client.Symbols.Symbol) _
            }
            graphicsLayer.Graphics.Add(graphic)
        End Sub

        Public Sub ShowFeatures(results As List(Of IdentifyResult))
            _dataItems = New List(Of DataItem)()

            If results IsNot Nothing AndAlso results.Count > 0 Then
                IdentifyComboBox.Items.Clear()
                For Each result As IdentifyResult In results
                    Dim feature As Graphic = result.Feature
                    Dim title As String = result.Value.ToString() & " (" & result.LayerName & ")"
                    _dataItems.Add(New DataItem() With { _
                     .Title = title, _
                     .Data = feature.Attributes _
                    })
                    IdentifyComboBox.Items.Add(title)
                Next

                IdentifyComboBox.UpdateLayout()
                IdentifyComboBox.SelectedIndex = 0
            End If
        End Sub

        Private Sub cb_SelectionChanged(sender As Object, e As SelectionChangedEventArgs)
            Dim index As Integer = IdentifyComboBox.SelectedIndex
            If index > -1 Then
                IdentifyDetailsDataGrid.ItemsSource = _dataItems(index).Data
            End If
        End Sub

        Private Sub IdentifyTask_ExecuteCompleted(sender As Object, args As IdentifyEventArgs)
            IdentifyDetailsDataGrid.ItemsSource = Nothing

            If args.IdentifyResults IsNot Nothing AndAlso args.IdentifyResults.Count > 0 Then
                IdentifyResultsPanel.Visibility = Visibility.Visible

                ShowFeatures(args.IdentifyResults)
            Else
                IdentifyComboBox.Items.Clear()
                IdentifyComboBox.UpdateLayout()

                IdentifyResultsPanel.Visibility = Visibility.Collapsed
            End If
        End Sub

        Public Class DataItem
            Public Property Title() As String
                Get
                    Return m_Title
                End Get
                Set(value As String)
                    m_Title = Value
                End Set
            End Property
            Private m_Title As String
            Public Property Data() As IDictionary(Of String, Object)
                Get
                    Return m_Data
                End Get
                Set(value As IDictionary(Of String, Object))
                    m_Data = Value
                End Set
            End Property
            Private m_Data As IDictionary(Of String, Object)
        End Class

        Private Sub IdentifyTask_Failed(sender As Object, e As TaskFailedEventArgs)
            MessageBox.Show("Identify failed. Error: " & Convert.ToString(e.[Error]))
        End Sub
    End Class

End Namespace