InformationDataProviderBase.LayerItemsGenerating Event

Occurs when a data provider starts generating map items for a layer.

Namespace: DevExpress.XtraMap

Assembly: DevExpress.XtraMap.v23.2.dll

NuGet Package: DevExpress.Win.Map

Declaration

C#

public event LayerItemsGeneratingEventHandler LayerItemsGenerating

VB.NET

Public Event LayerItemsGenerating As LayerItemsGeneratingEventHandler

Event Data

The LayerItemsGenerating event's data class is LayerItemsGeneratingEventArgs. The following properties provide information specific to this event:

Property	Description
Cancelled	Gets a value indicating whether an asynchronous operation has been canceled. Inherited from AsyncCompletedEventArgs.
Error	Gets a value indicating which error occurred during an asynchronous operation. Inherited from AsyncCompletedEventArgs.
Items	Returns all the items generated for the layer.
UserState	Gets the unique identifier for the asynchronous task. Inherited from AsyncCompletedEventArgs.

The event data class exposes the following methods:

Method	Description
RaiseExceptionIfNecessary()	Raises a user-supplied exception if an asynchronous operation failed. Inherited from AsyncCompletedEventArgs.

Example

View Example

Form1.cs

void OnLayerItemsGenerating(object sender, LayerItemsGeneratingEventArgs e) {
    foreach(MapItem item in e.Items) {
        MapPolyline polyline = item as MapPolyline;
        if(polyline != null) {
            polyline.Stroke = Color.FromArgb(0xFF, 0x00, 0x72, 0xC6);
            polyline.StrokeWidth = 4;
        }
    }
}

Form1.vb

Private Sub OnLayerItemsGenerating(ByVal sender As Object, ByVal e As LayerItemsGeneratingEventArgs)
    For Each item As MapItem In e.Items
        Dim polyline As MapPolyline = TryCast(item, MapPolyline)
        If polyline IsNot Nothing Then
            polyline.Stroke = Color.FromArgb(&HFF, &H0, &H72, &HC6)
            polyline.StrokeWidth = 4
        End If
    Next item
End Sub

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the LayerItemsGenerating event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

winforms-map-calculate-routes-from-major-roads/CS/CalculateRoutesFromMajorRoads/Form1.cs#L29

routeProvider = new BingRouteDataProvider { BingKey = yourBingKey };
routeProvider.LayerItemsGenerating += OnLayerItemsGenerating;
routeProvider.RouteCalculated += OnRouteCalculated;

winforms-map-get-geo-point-info-from-bing-geocode-service/CS/RequestLocationInformation/Form1.cs#L32

geocodeProvider.LocationInformationReceived += OnLocationInformationReceived;
geocodeProvider.LayerItemsGenerating += OnLayerItemsGenerating;
informationLayer.DataProvider = geocodeProvider;

VB.NET

winforms-map-calculate-routes-from-major-roads/VB/CalculateRoutesFromMajorRoads/Form1.vb#L36

routeProvider = New BingRouteDataProvider With {.BingKey = yourBingKey}
AddHandler routeProvider.LayerItemsGenerating, AddressOf OnLayerItemsGenerating
AddHandler routeProvider.RouteCalculated, AddressOf OnRouteCalculated

winforms-map-get-geo-point-info-from-bing-geocode-service/VB/RequestLocationInformation/Form1.vb#L40

AddHandler geocodeProvider.LocationInformationReceived, AddressOf OnLocationInformationReceived
AddHandler geocodeProvider.LayerItemsGenerating, AddressOf OnLayerItemsGenerating
informationLayer.DataProvider = geocodeProvider