private void OnLayerPropertyChanged(object sender, PropertyChangedEventArgs e)
{
var layer = sender as Layer;
if (layer == null)
{
return;
}
if (e.PropertyName == "MinScale")
{
MinimumScale = Layer.MinScale != 0 && !double.IsNaN(Layer.MinScale)
? Math.Min(_serviceMinScale, Layer.MinScale)
: _serviceMinScale;
if (LegendTree != null)
{
LegendTree.UpdateLayerVisibilities();
}
}
else if (e.PropertyName == "MaxScale")
{
MaximumScale = !double.IsNaN(Layer.MaxScale)
? Math.Max(_serviceMaxScale, Layer.MaxScale)
: _serviceMaxScale;
if (LegendTree != null)
{
LegendTree.UpdateLayerVisibilities();
}
}
else if (e.PropertyName == "IsVisible")
{
if (LegendTree != null)
{
LegendTree.UpdateLayerVisibilities();
}
}
else if (e.PropertyName == "DisplayName")
{
Label = layer.DisplayName;
}
else if (e.PropertyName == "Status")
{
//if (!(sender is GroupLayerBase)) // For group layers, we don't wait for initialized event
Refresh();
}
}
/// <summary>
/// Refreshes the legend from infos coming from the map layer.
/// </summary>
internal async void Refresh()
{
if (_isQuerying || Layer == null)
{
return; // already querying
}
//if (!(Layer is GroupLayerBase)) // GroupLayer : don't wait for layer intialized, so the user will see the layer hierarchy even if the group layer is not initialized yet (else would need to wait for all sublayers initialized)
//{
if (Layer.Status < LayerStatus.Initialized)
{
IsBusy = true; // set busy indicator waiting for layer initialized
return; // Refresh will be done on event Initialized
}
LayerItems = null;
//}
LegendItems = null;
if (Layer is ILegendSupport)
{
IsBusy = true;
_isQuerying = true;
var legendSupport = Layer as ILegendSupport;
LayerLegendInfo result = null;
Exception exception = null;
try
{
result = await legendSupport.GetLegendInfosAsync();
}
catch (Exception ex)
{
exception = ex;
}
if (LegendTree == null)
{
// The legend item has been detached ==> result no more needed
IsBusy = _isQuerying = false;
return;
}
if (exception != null)
{
// Fire event Refreshed with an exception
if (LegendTree != null)
{
LegendTree.OnRefreshed(this, new Legend.RefreshedEventArgs(this, exception));
}
_isQuerying = false;
IsBusy = false;
return;
}
if (result != null)
{
Description = result.LayerDescription;
if (string.IsNullOrEmpty(Label)) // Label is set with LayerID : keep it if not null
{
Label = result.LayerName;
}
// Combine Layer and Service scale
double minScale = result.MinimumScale == 0.0 ? double.PositiveInfinity : result.MinimumScale;
_serviceMinScale = minScale;
if (Layer.MinScale != 0.0 && !double.IsNaN(Layer.MinScale))
{
minScale = Math.Min(minScale, Layer.MinScale);
}
double maxScale = result.MaximumScale;
_serviceMaxScale = maxScale;
if (!double.IsNaN(Layer.MaxScale))
{
maxScale = Math.Max(maxScale, Layer.MaxScale);
}
MinimumScale = minScale;
MaximumScale = maxScale;
IsHidden = result.IsHidden;
// For feature layers, force the geometry type since GeometryType.Unknown doesn't work well with advanced symbology.
Geometry.GeometryType geometryType = Geometry.GeometryType.Unknown;
if (Layer is FeatureLayer)
{
var fl = Layer as FeatureLayer;
if (fl.FeatureTable != null && fl.FeatureTable.ServiceInfo != null)
{
geometryType = fl.FeatureTable.ServiceInfo.GeometryType;
}
}
if (result.LayerLegendInfos != null)
{
LayerItems = result.LayerLegendInfos.Select(info => new LayerItemViewModel(Layer, info, Description)).ToObservableCollection();
}
if (result.LegendItemInfos != null)
{
LegendItems = result.LegendItemInfos.Select(info => new LegendItemViewModel(info, geometryType)).ToObservableCollection();
}
}
// If groupLayer -> add the child layers
//AddGroupChildLayers();
// Kml layer particular case : if a KML layer has only a child which is not another KML layer ==> set the child item as transparent so it doesn't appear in the legend
//ProcessKmlLayer();
LegendTree.UpdateLayerVisibilities();
_isQuerying = false;
// Fire event Refreshed without exception
LegendTree.OnRefreshed(this, new Legend.RefreshedEventArgs(this, null));
IsBusy = false;
}
else
{
IsBusy = false;
// Fire event Refreshed
if (LegendTree != null)
{
LegendTree.OnRefreshed(this, new Legend.RefreshedEventArgs(this, null));
}
}
}