On Demand FeatureLayer

This sample demonstrates selecting individual features in a local feature layer using OnDemand mode. Only the features in the current map extent are retrieved. As the map extent changes, additional features are requested. The features are renderered using a SimpleRenderer with a SimpleFillSymbol defined MapTips.

XAML

<UserControl x:Class="ArcGISWPFSDK.LocalFeatureLayerOnDemand"
    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">
        <Grid.Resources>
            <BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
            <esri:SimpleRenderer x:Key="MySimplePolygonRenderer">
                <esri:SimpleRenderer.Symbol>
                    <esri:SimpleFillSymbol Fill="#440000FF"/>
                </esri:SimpleRenderer.Symbol>
            </esri:SimpleRenderer>
            <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" WrapAround="True" Background="#FFE3E3E3" MinimumResolution="2445.98490512499">
            <esri:ArcGISLocalTiledLayer ID="TopoMapLayer"
                  Path="..\\Data\\TPKs\\Topographic.tpk"/>
            <esri:ArcGISLocalFeatureLayer ID="States" LayerName="States" 
                   Path="..\\Data\\MPKS\\USCitiesStates.mpk"   
                Mode="OnDemand" 
                Renderer="{StaticResource MySimplePolygonRenderer}" 
                OnDemandCacheSize="500" 
                OutFields="*">
                <esri:ArcGISLocalFeatureLayer.MapTip>
                    <Border CornerRadius="10" BorderBrush="Black" BorderThickness="2" Margin="0,0,15,15" Background="{StaticResource PanelGradient}" >                
                           <StackPanel Margin="7">
                            <StackPanel Orientation="Vertical">
                                <TextBlock Text="State: " FontWeight="Bold" Foreground="White"/>
                                <TextBlock Text="{Binding [STATE_NAME]}" Foreground="White" />
                                <TextBlock Text="Population: " FontWeight="Bold" Foreground="White"/>
                                <TextBlock Text="{Binding [POP2010]}" Foreground="White" />
                            </StackPanel>
                        </StackPanel>
                    </Border>
                </esri:ArcGISLocalFeatureLayer.MapTip>
            </esri:ArcGISLocalFeatureLayer>
        </esri:Map>
        <Grid HorizontalAlignment="Left" VerticalAlignment="Top" Margin="10,10,10,0" >
            <Rectangle Fill="{StaticResource PanelGradient}" Stroke="Gray"  RadiusX="10" RadiusY="10" Margin="0,0,0,5">
                <Rectangle.Effect>
                    <DropShadowEffect/>
                </Rectangle.Effect>
            </Rectangle>
            <Rectangle Fill="#DDFFFFFF" Stroke="DarkGray" RadiusX="5" RadiusY="5" Margin="10,10,10,15" />
            <TextBlock x:Name="ResponseTextBlock" Text="The feature layer is in OnDemand mode. Only features within the current map extent are retrieved.  As the map extent changes, additional features are requested." 
                       Width="200" TextAlignment="Left" Margin="30,20,20,30" TextWrapping="Wrap" Foreground="Black" />
        </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.Windows.Controls;
using System.ComponentModel;


namespace ArcGISWPFSDK
{
    public partial class LocalFeatureLayerOnDemand : 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 static ESRI.ArcGIS.Client.Projection.WebMercator mercator = new ESRI.ArcGIS.Client.Projection.WebMercator();

        ESRI.ArcGIS.Client.Geometry.Envelope initialExtent = new ESRI.ArcGIS.Client.Geometry.Envelope(
                mercator.FromGeographic(new ESRI.ArcGIS.Client.Geometry.MapPoint(-117.190346717, 34.0514888762)) as ESRI.ArcGIS.Client.Geometry.MapPoint,
                mercator.FromGeographic(new ESRI.ArcGIS.Client.Geometry.MapPoint(-117.160305976, 34.072946548)) as ESRI.ArcGIS.Client.Geometry.MapPoint)
        {
            SpatialReference = new ESRI.ArcGIS.Client.Geometry.SpatialReference(102100)
        };

        public LocalFeatureLayerOnDemand()
        {
            InitializeComponent();

            MyMap.Extent = initialExtent;

            DataContext = this;

            MyMap.Layers.LayersInitialized += (o, evt) =>
            {
                IsBusy = false;

            };
        }
    }
}

VB.NET

Imports System.Windows.Controls
Imports System.ComponentModel

Namespace ArcGISWPFSDK
    Partial Public Class LocalFeatureLayerOnDemand
        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 Shared mercator As New ESRI.ArcGIS.Client.Projection.WebMercator()

        Private initialExtent As New ESRI.ArcGIS.Client.Geometry.Envelope(TryCast(mercator.FromGeographic(New ESRI.ArcGIS.Client.Geometry.MapPoint(-117.190346717, 34.0514888762)), ESRI.ArcGIS.Client.Geometry.MapPoint), TryCast(mercator.FromGeographic(New ESRI.ArcGIS.Client.Geometry.MapPoint(-117.160305976, 34.072946548)), ESRI.ArcGIS.Client.Geometry.MapPoint)) With { _
         .SpatialReference = New ESRI.ArcGIS.Client.Geometry.SpatialReference(102100) _
        }
        Public Sub New()
            InitializeComponent()
            AddHandler MyMap.Layers.LayersInitialized, AddressOf map_LayersInitialized
            MyMap.Extent = initialExtent
        End Sub
        Private Sub map_LayersInitialized(sender As Object, e As EventArgs)
            DataContext = Me
            IsBusy = False
        End Sub
    End Class
End Namespace