Null llist of visible layers after Custom Identify tool initiliazed

[AdamDunlap]

Hi All,

I have a Dynamic Map Service Layer and when I try to identify the layers in the service, initially I get null visible layers.  Yet if I  turn some of the layers on or off, and then use the identify tool, the list-update is triggered and I have a viable list for visible layers...

What am I missing on map load/start up and what am I missing otherwise?

Code Behind (C#)

void Map_MouseClick(object sender, Map.MouseEventArgs e)
        {

          ArcGISDynamicMapServiceLayer dsl = MapApplication.Current.Map.Layers[MapUtilities.getAppSetting("MainMapService")] as ArcGISDynamicMapServiceLayer;
        
            int[] visibleLayerIDList = dsl.VisibleLayers;  // often is null on initial map load and mouse click
            ESRI.ArcGIS.Client.Geometry.MapPoint clickPoint = e.MapPoint;
            PrevMapArgs = e;
            ESRI.ArcGIS.Client.Tasks.IdentifyParameters identifyParams = new ESRI.ArcGIS.Client.Tasks.IdentifyParameters()
            {
                Geometry = clickPoint,
                MapExtent = MapApplication.Current.Map.Extent,
                Width = (int)MapApplication.Current.Map.ActualWidth,
                Height = (int)MapApplication.Current.Map.ActualHeight,
                LayerOption = ESRI.ArcGIS.Client.Tasks.LayerOption.all,
                SpatialReference = MapApplication.Current.Map.SpatialReference,
                Tolerance = 10,
                //LayerDefinitions = dsl.LayerDefinitions
            };

            GraphicsLayer graphicsLayer = MapApplication.Current.Map.Layers["SelectionGraphicsLayer"] as GraphicsLayer;
            graphicsLayer.ClearGraphics();

            dataviewer3.AddIns.CustomIdentify c = new CustomIdentify();
            Graphic graphic = new Graphic()
            {
                Geometry = e.MapPoint,
                Symbol = c.Resources["IdentifySearchingSymbol"] as ESRI.ArcGIS.Client.Symbols.MarkerSymbol
            };

            graphicsLayer.Graphics.Add(graphic);

            ESRI.ArcGIS.Client.Tasks.IdentifyTask identifyTask = new ESRI.ArcGIS.Client.Tasks.IdentifyTask(dsl.Url);
            identifyTask.ExecuteCompleted += new EventHandler<ESRI.ArcGIS.Client.Tasks.IdentifyEventArgs>(identifyTask_ExecuteCompleted);
            identifyTask.ExecuteAsync(identifyParams, visibleLayerIDList);  // often is null on initial map load

        }


void identifyTask_ExecuteCompleted(object sender, ESRI.ArcGIS.Client.Tasks.IdentifyEventArgs e)
        {
            //MapUtilities.getAppSetting("DigPermitMapService")
           // ArcGISDynamicMapServiceLayer dsl = ESRI.ArcGIS.Client.Extensibility.MapApplication.Current.Map.Layers["ANAD_Main"] as ArcGISDynamicMapServiceLayer;

            ArcGISDynamicMapServiceLayer dsl = MapApplication.Current.Map.Layers[MapUtilities.getAppSetting("MainMapService")] as ArcGISDynamicMapServiceLayer;
            int[] visibleLayerIDList = dsl.VisibleLayers;

            if (dsl.VisibleLayers == null)
            {

                MessageBox.Show("You've selected in a area w/o visible data or your faster than the server, please try again");
            }

            else
            {
     
            dataviewer3.AddIns.CustomIdentify c = new CustomIdentify();
            c.IdentifyComboBox.Items.Clear();
            // Check for new results
            if (e.IdentifyResults.Count > 0)
            {
                // Show ComboBox and attributes DataGrid
                c.IdentifyResultsStackPanel.Visibility = Visibility.Visible;

                c.LastIdentifyResult = new List<ESRI.ArcGIS.Client.Tasks.IdentifyResult>();

                // Add results to ComboBox
                foreach (ESRI.ArcGIS.Client.Tasks.IdentifyResult result in e.IdentifyResults)
                {
                    int find = Array.IndexOf(visibleLayerIDList, result.LayerId);
                    if (find != -1)
                    {
                        string title = string.Format("{0} ({1})", result.Value.ToString(), result.LayerName);
                        c.IdentifyComboBox.Items.Add(title);
                        c.LastIdentifyResult.Add(result);
                    }
                }

                if (c.IdentifyComboBox.Items.Count > 0)
                {

                    // Workaround for ComboBox bug
                    c.IdentifyComboBox.UpdateLayout();

                    // Initialize ComboBox and fire SelectionChanged
                    c.IdentifyComboBox.SelectedIndex = 0;

                    if (!this.Window.IsOpen)
                    {
                        this.Window.Name = "Identify";
                        this.Window.Content = c;
                        this.Window.WindowStartupLocation = Telerik.Windows.Controls.WindowStartupLocation.Manual;
                        Telerik.Windows.Controls.StyleManager.SetTheme(this.Window, new Telerik.Windows.Controls.Windows7Theme());
                        this.Window.ResizeMode = Telerik.Windows.Controls.ResizeMode.NoResize;
                        double thewidth = MapApplication.Current.Map.ActualWidth;
                        double theheight = MapApplication.Current.Map.ActualHeight;

                        this.Window.Left = thewidth - 410;
                        this.Window.Top = 100;
                        this.Window.Header = "Identify Results";
                        this.Window.Height = theheight - 300;
                        this.Window.MinWidth = 400;
                        this.Window.MaxWidth = 400;
                        this.Window.Show();
                    }
                    else
                    {
                        this.Window.Content = c;

                    }

                    GraphicsLayer graphicsLayer = MapApplication.Current.Map.Layers["SelectionGraphicsLayer"] as GraphicsLayer;
                    graphicsLayer.ClearGraphics();

                    Graphic graphic = new Graphic()
                    {
                        Geometry = PrevMapArgs.MapPoint,
                        Symbol = c.Resources["IdentifyPointSymbol"] as ESRI.ArcGIS.Client.Symbols.MarkerSymbol
                    };

                    graphicsLayer.Graphics.Add(graphic);
                }
                else
                {
                    GraphicsLayer graphicsLayer = MapApplication.Current.Map.Layers["SelectionGraphicsLayer"] as GraphicsLayer;
                    graphicsLayer.ClearGraphics();
                    MessageBox.Show("There were no features found at that point.");
                }
            }
            else
            {
                // Hide ComboBox and attributes DataGrid and notify user
                c.IdentifyResultsStackPanel.Visibility = Visibility.Collapsed;
                GraphicsLayer graphicsLayer = MapApplication.Current.Map.Layers["SelectionGraphicsLayer"] as GraphicsLayer;
                graphicsLayer.ClearGraphics();
                MessageBox.Show("There were no features found at that point.");
            }
         }
        }