Developing New Data Visualizers

Modified on Tuesday, 12 July 2011 11:17 AM by Administrator Categorized as Data Visualizers, Feature
New data visualizers can be created by developers by implementing the interface IDataVisualizer. The Data Visualizer is given a set of features that it responds back to the framework if it can visualize the data set. The Data Visualizer is responsible for showing, hiding, and removing itself.[imageright|Data Visualizer list {br} in the framework|{UP(GisFramework.DevelopingNewDataVisualizers)}datavisualizer.png]

{toc}

==IDataVisualizer==
The interface IDataVisualizer needs to be implemented and the made exportable through MEF.

====Properties====
{| class="tablesorter"
! Name !! Type !! Description
|-
| IsInitialized || bool || Returns to the framework if the data visualizer is initialized.
|-
| Name || string || The name of the data visualizer that is displayed in the framework.
|}

====Methods====
{| class="tablesorter"
! Name !! Return Type !! Description
|-
| CanVisualize(IEnumerable<[GisFramework.Feature|Feature]> data) || bool || Given a set of features the data visualizer must return if it can visualize or not visualize the features.
|-
| Hide() || void || Hides the visualization from the current view.
|-
| Initialize(IDictionary<string, string> customSettings) || void || Initializes the data visualizer and allows the intake of custom settings from configuration.
|-
| ReloadData(IEnumerable<[GisFramework.Feature|Feature]>data) || void || Reloads the given visualization when the dataset has changed based on a filter or some other action.
|-
| Remove() || void || Removes the data visualizers. '''If the Data Visualizers is using any GraphicsManagers or other resources that are disposable they should be disposed on this method call.'''
|-
| Show() || void || Shows the data visualizer.
|-
| Visualize(IEnumerable<[GisFramework.Feature|Feature]>data) || void || Performs the data visualization and shows the results.
|}

==IDialogDataVisualizer==
If the Data Visualizer wants to display a dialog to have user controllable settings then it needs to implement the interface IDialogDataVisualizer.<div class="imageright"><img class="image" src="GetFile.aspx?Page=GisFramework.DevelopingNewDataVisualizers&amp;File=DataVisualizerDialog.png" alt="IDialogDataVisualizer Dialog Button"><p class="imagedescription">IDialogDataVisualizer Dialog Button</div> The Data Visualizer has a dialog button next to for DataVisualizers which implement IDialogDataVisualizer.

====Methods====
{| class="tablesorter"
! Name !! Type !! Description
|-
| ShowDialog(IEnumerable<[GisFramework.Feature|Feature]> data) || void || The logic that shows the dialog that is associated with the data visualizer should be placed in this method.
|}
==Example==
Here's the source code from the FlareClustererVisualizer:

(((@@    [Export(typeof(IDataVisualizer))]
    public class FlareClustererVisualizer : IDataVisualizer
    {
        private readonly Symbol _symbol;

        public FlareClustererVisualizer()
        {
            _symbol = SymbolManager.GetSymbol("MediumMarkerSymbol");
        }

        public string Name
        {
            get { return "Cluster Graphics"; }
        }

        public bool CanVisualize(IEnumerable<Feature> data)
        {
            if (data != null && data.Any())
            {
                if (data.First().Geometry == null)
                    return false;

                return data.First().Geometry.GeometryType.ToUpper() == "ESRIGEOMETRYPOINT" || data.First().Geometry.GeometryType.ToUpper() == "ESRIGEOMETRYPOLYGON";
            }
            return false;
        }

        public void Visualize(IEnumerable<Feature> data)
        {
            LoadFlareClusterer(data);
            if (!MapHandler.CurrentMap.Layers.Contains(GraphicsLayer))
            { MapHandler.CurrentMap.Layers.Add(GraphicsLayer); }
        }

        public void Hide()
        { GraphicsLayer.Visible = false; }

        public void Remove()
        {
            GraphicsLayer.Graphics.Clear();
            MapHandler.CurrentMap.Layers.Remove(GraphicsLayer);
        }

        public void Show()
        { GraphicsLayer.Visible = true; }

        public void ReloadData(IEnumerable<Feature> data)
        {
            GraphicsLayer.Graphics.Clear();
            FeatureMap.Clear();
            LoadFlareClusterer(data);
        }

        public bool HasPopup
        {
            get { return false; }
        }


        private GraphicsLayer _graphicsLayer;
        private GraphicsLayer GraphicsLayer
        {
            get
            {
                if (_graphicsLayer == null)
                { _graphicsLayer = new GraphicsLayer { Clusterer = new CustomFlareClusterer { MaximumFlareCount = 9 } }; }
                return _graphicsLayer;
            }
        }


        private Dictionary<Graphic, Feature> _featureMap = null;
        private Dictionary<Graphic, Feature> FeatureMap
        {
            get
            {
                if (_featureMap == null)
                { _featureMap = new Dictionary<Graphic, Feature>(); }
                return _featureMap;
            }
        }


        #region private methods
        private void LoadFlareClusterer(IEnumerable<Feature> features)
        {
            var newFeatures = features.Except(FeatureMap.Values);

            foreach (var feature in newFeatures)
            {
                DataContracts.Geometry geometry;
                if (feature.Geometry.GeometryType.ToUpper() == "ESRIGEOMETRYPOLYGON")
                { geometry = (DataContracts.Geometry)feature.Geometry.GetCentroid(); }
                else
                { geometry = feature.Geometry; }

                var g = new Graphic { Symbol = _symbol, Geometry = GeometryTranslator.Translate(geometry) };
                //foreach (var kvp in feature.Attributes)
                //{ g.Attributes.Add(kvp.Key.Description, kvp.Value); }

                FeatureMap.Add(g, feature);
                GraphicsLayer.Graphics.Add(g);
            }

            // uncomment this one to have the map tips show on hover
            MapHandler.CurrentMap.MouseMove += new MouseEventHandler(MouseEnter);

            // uncomment this one to have the map tips show on click
            //MapHandler.CurrentMap.MouseLeftButtonUp += new MouseButtonEventHandler(MouseEnter);
        }


        private FlareMapTip _currentMapTip = null;
        private void MouseEnter(object sender, MouseEventArgs e)
        {
            if (!(e.OriginalSource is Ellipse) && !(e.OriginalSource is FlareMapTip))
            {
                if (_currentMapTip != null)
                { _currentMapTip.Hide(); }

                return;
            }
            GeneralTransform generalTransform = MapHandler.CurrentMap.TransformToVisual(Application.Current.RootVisual);
            Point transformScreenPnt = generalTransform.Transform(e.GetPosition(MapHandler.CurrentMap));
            var graphics = GraphicsLayer.FindGraphicsInHostCoordinates(transformScreenPnt);

            var flareMapTip = sender as FlareMapTip;
            if (flareMapTip != null)
            { flareMapTip.MapTip_MouseEnter(sender, e); }

            var flareClusterer = GraphicsLayer.Clusterer as CustomFlareClusterer;
            if (flareClusterer != null)
            {
                Graphic flare = null;
                if (graphics.Count() > 1)
                { flare = flareClusterer.FindGraphicByEllipse(graphics, e.OriginalSource as Ellipse); }
                else
                { flare = graphics.FirstOrDefault(); }

                if (flare != null)
                {
                    var feature = _featureMap[flare] as Feature;
                    if (feature != null)
                    {
                        feature.IsSelected = true;
                        MapHandler.MapTip.Show(e);
                    }
                }
            }
        }
        #endregion

        /// <summary>
        /// Returns true if the data visualizer has been initialized.
        /// </summary>
        public bool IsInitialized { get; private set; }

        /// <summary>
        /// Initialize the data visualizer with the provided settings.
        /// </summary>
        /// <param name="customSettings"></param>
        public void Initialize(IDictionary<string, string> customSettings)
        {
            if (!IsInitialized)
                OnInitialize(customSettings);

            IsInitialized = true;
        }

        protected virtual void OnInitialize(IDictionary<string, string> customSettings)
        { }
    }@@)))
==See Also==
{incoming}
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Developing New Data Visualizers
