[Solved] RadMap - selected shape collection?

[Robert]

Having some great experience with RadMap so far--great job on it!

I'd like to be able to get some access to the collection of shapes in order to inspect them as well as possibly select/unselect them programmatically.  However I can't really find any way to do that....

I can detect when a shape is tapped on using my ShapeSelectionChanged command...so I have *some* access to what's going on.  However I'd like to do things like:

-- clear all shape selections programatically

-- only allow a user to select two shapes (clearing the oldest)--for example choose two US States and see a side-by-side comparison

Any hints how to do things like these would be greatly appreciated!

[Giuseppe]

Hello Robert,

Onto your questions:

• You can get the selected shapes through the MapShapeSelectionBehavior.SelectedShapes property.
• You can use the MapShapeSelectionBehavior.ClearSelection() method to clear the selected shapes, however, only single selection is supported programmatically through the MapShapeSelectionBehavior.SelectedShape property.
• If the default MapShapeSelectionBehavior.SelectionMode options do not suit your scenario, you can create custom MapShapeSelectionBehavior. You can check the Map First Look example in our demo application that implements custom selection behavior (single shape selection per map layer) to get you started:

/// <summary>
/// Implements custom single selection mode per layer.
/// </summary>
public class MapSingleSelectionPerLayerBehavior : MapShapeSelectionBehavior
{
    private Dictionary<MapLayer, IMapShape> selectedShapesPerLayer;
    private IList<object> shapesToRemove;

    /// <summary>
    /// Initializes a new instance of the <see cref="MapSingleSelectionPerLayerBehavior"/> class.
    /// </summary>
    public MapSingleSelectionPerLayerBehavior()
    {
        this.SelectionMode = MapShapeSelectionMode.MultiExtended;

        this.selectedShapesPerLayer = new Dictionary<MapLayer, IMapShape>();
        this.shapesToRemove = new List<object>();
    }

    /// <summary>
    /// Initiates a hit test on the specified <see cref="T:Windows.Foundation.Point" /> location.
    /// </summary>
    /// <param name="location">The location.</param>
    /// <returns></returns>
    /// <remarks>
    /// The default <see cref="T:Telerik.UI.Xaml.Controls.Map.MapBehavior" /> logic returns only the top-most <see cref="T:Telerik.UI.Drawing.D2DShape" /> from the <see cref="T:Telerik.UI.Xaml.Controls.Map.MapShapeLayer" /> that matches the specific behavior requirements;
    /// you can override the default logic and return multiple <see cref="T:Telerik.UI.Drawing.D2DShape" /> instances (e.g. from layers that overlay one another) and the specific <see cref="T:Telerik.UI.Xaml.Controls.Map.MapBehavior" /> will
    /// manipulate all of them.
    /// </remarks>
    protected override IEnumerable<IMapShape> HitTest(Point location)
    {
        int layerCount = this.Map.Layers.Count;
        for (int i = layerCount - 1; i >= 0; i--)
        {
            var layer = this.Map.Layers[i] as MapShapeLayer;
            if (layer == null || !layer.IsSelectionEnabled)
            {
                continue;
            }

            var newShape = this.Map.HitTest(location, layer);

            if (this.selectedShapesPerLayer.ContainsKey(layer))
            {
                var oldShape = this.selectedShapesPerLayer[layer];

                // Disallow toggle selection.
                if (newShape == null || newShape == oldShape)
                {
                    continue;
                }

                if (oldShape != null)
                {
                    this.shapesToRemove.Add(oldShape);
                }
            }

            this.selectedShapesPerLayer[layer] = newShape;

            yield return newShape;
        }
    }

    /// <summary>
    /// Raises the <see cref="F:Telerik.UI.Xaml.Controls.Map.CommandId.ShapeSelectionChanged" /> command and the <see cref="E:Telerik.UI.Xaml.Controls.Map.MapShapeSelectionBehavior.SelectionChanged" /> event.
    /// </summary>
    /// <param name="removedItems">The removed items.</param>
    /// <param name="addedItems">The added items.</param>
    protected override void OnSelectionChanged(IList<object> removedItems, IList<object> addedItems)
    {
        base.OnSelectionChanged(this.shapesToRemove, addedItems);

        this.shapesToRemove.Clear();
    }
}

Hope this helps.



Regards,
Giuseppe
Telerik

[Robert]

Thanks for the quick reply, Guiseppe.  Very helpful indeed.  Multi-select on the map would be helpful especially in use cases like dashboards where it's common to aggregate multi-select, e.g. "What are sales in New York and New Jersey?"

[Giuseppe]

Hello Robert,

Thank you for elaborating on this.

You can log your feature request on supporting multiple shape selection programmatically in our Windows 8 feedback portal here so the community members can vote for it (and raise its priority).


Regards,
Giuseppe
Telerik