Using GraphicsSource Online

This sample demonstrates how to create a graphics layer by binding to a source of items (i.e. graphics). The GraphicsSource property should reference an IEnumerable of Graphic objects (such as ObservableCollection). The appropriate event mechanisms are in place so changes in the items are reflected in the graphics layer.

XAML

<UserControl x:Class="ArcGISWPFSDK.UsingGraphicsSource"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"
    xmlns:local="clr-namespace:ArcGISWPFSDK">
    <Grid x:Name="LayoutRoot" Background="#FFE3E3E3">
        <Grid.Resources>
            <local:Customers x:Key="customers" />
        </Grid.Resources>
        <esri:Map x:Name="MyMap">
            <esri:ArcGISTiledMapServiceLayer 
                Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer" />
            <esri:GraphicsLayer ID="MyGraphicsLayer" 
                                GraphicsSource="{StaticResource customers}" />
        </esri:Map>
    </Grid>
</UserControl>

C#

using System;
using System.Collections.ObjectModel;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Threading;
using ESRI.ArcGIS.Client;
using ESRI.ArcGIS.Client.Geometry;
using ESRI.ArcGIS.Client.Symbols;

namespace ArcGISWPFSDK
{
    public partial class UsingGraphicsSource : UserControl
    {
        public UsingGraphicsSource()
        {
            InitializeComponent();
        }
    }

    public class Customers : ObservableCollection<Graphic>
    {
        Random random;
        
        private static ESRI.ArcGIS.Client.Projection.WebMercator mercator =
            new ESRI.ArcGIS.Client.Projection.WebMercator();

        public Customers()
        {
            DispatcherTimer timer = new DispatcherTimer() { Interval = TimeSpan.FromSeconds(1) };
            timer.Tick += new EventHandler(timer_Tick);
            timer.Start();
        }

        void timer_Tick(object sender, EventArgs e)
        {
            ClearItems();

            random = new Random();

            for (int i = 0; i < 10; i++)
            {
                Graphic g = new Graphic()
                {
                    Geometry = new MapPoint(random.Next(-20000000, 20000000), random.Next(-20000000, 20000000))
                };

                g.Symbol = new SimpleMarkerSymbol()
                {
                    Color = new SolidColorBrush(Color.FromArgb(255, (byte)random.Next(0, 255), (byte)random.Next(0, 255), (byte)random.Next(0, 255))),
                    Size = 24
                };

                Add(g);
            }
        }
    }
}

VB.NET

Imports System.Collections.ObjectModel
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Threading
Imports ESRI.ArcGIS.Client
Imports ESRI.ArcGIS.Client.Geometry
Imports ESRI.ArcGIS.Client.Symbols

Namespace ArcGISWPFSDKVB
    Partial Public Class UsingGraphicsSource
        Inherits UserControl
        Public Sub New()
            InitializeComponent()
        End Sub
    End Class

    Public Class Customers
        Inherits ObservableCollection(Of Graphic)
        Private random As Random

        Private Shared mercator As New ESRI.ArcGIS.Client.Projection.WebMercator()

        Public Sub New()
            Dim timer As New DispatcherTimer() With { _
             .Interval = TimeSpan.FromSeconds(4) _
            }
            AddHandler timer.Tick, New EventHandler(AddressOf timer_Tick)
            timer.Start()
        End Sub

        Private Sub timer_Tick(sender As Object, e As EventArgs)
            ClearItems()

            random = New Random()

            For i As Integer = 0 To 9
                Dim g As New Graphic() With { _
                 .Geometry = New MapPoint(random.[Next](-20000000, 20000000), random.[Next](-20000000, 20000000)) _
                }

                g.Symbol = New SimpleMarkerSymbol() With { _
                 .Color = New SolidColorBrush(Color.FromArgb(255, CByte(random.[Next](0, 255)), CByte(random.[Next](0, 255)), CByte(random.[Next](0, 255)))), _
                 .Size = 24 _
                }

                Add(g)
            Next
        End Sub
    End Class
End Namespace