Use of AsyncReaderSourceCollection with VirtualizationSource

[Alice]

I'm experimenting with AsyncShapeFileReader using the provided example. It works as expected with AsyncShapeFileReader's Source and DataSource properties set. The only thing I wish to change in the example is to use AsyncReaderSourceCollection to asyncronously load multiple shape files and benefit UI Virtualization.

01.<telerik:VisualizationLayer.VirtualizationSource>
02.    <telerik:MapShapeDataVirtualizationSource>
03.        <telerik:MapShapeDataVirtualizationSource.Reader>
04.            <telerik:AsyncShapeFileReader x:Name="mapShapeDataReader">
05.                <telerik:AsyncReaderSourceCollection>
06.                    <telerik:AsyncReaderSource Source="/MyProject;component/Resources/myshape1.shp" DataSource="/MyProject;component/Resources/myshape1.dbf" />
07.                    <telerik:AsyncReaderSource Source="/MyProject;component/Resources/myshape2.shp" DataSource="/MyProject;component/Resources/myshape2.dbf" />
08.                </telerik:AsyncReaderSourceCollection>
09.            </telerik:AsyncShapeFileReader>
10.        </telerik:MapShapeDataVirtualizationSource.Reader>
11.    </telerik:MapShapeDataVirtualizationSource>
12.</telerik:VisualizationLayer.VirtualizationSource>

Visualization layer displays only the last AsyncReaderSource (myshape2.shp), although ReadShapeDataCompleted is called twice without exception. I wonder is it possible to load multiple shapes asynchronously and benefit Items Virtualization?

[Andrey]

Hello Alice,

You should set the MapShapeDataVirtualizationSource.ClearCache property to 'False' when you use the AsyncReaderSourceCollection.
The sample code is below.

<telerik:MapShapeDataVirtualizationSource ClearCache="False">
...
</telerik:MapShapeDataVirtualizationSource>

Regards,
Andrey Murzov
Telerik

 

 

[Alice]

thanks alot for help, problem solve

[brousouf]

Hello,
I'm trying to load many KML files from code behind. It works fine with one KML, but I'm not able to make it work with many of them, (loading from code behind, not in XAML).
Thanks a lot

[Petar Mladenov]

Hi brousouf,

Is it possible for you to open a new support ticket with more details about your scenario ? What type of Layer do you use ? Can you send us an isolated sample that we can better investigate? Thank you in advance for your cooperation.

Regards,
Petar Mladenov
Telerik

 

 

[Sanjay]

Hi Petar

1. Can you share C# code for implementing VisualizationLayer.VirtualizationSource ,i.e I wish to create Virtualization layer object at runtime, define and add MapShapeDataVirtualizationSource AsyncShapeFileReader  in MapShapeDataVirtualizationSource, and 
setting its source to URI shapefile.

2. How many Virtualization layers can i add to radMap.

3. What is the maximum size of shapefile in MB which radMap WPF engine can render without UI responsive issue.

4. I have some 3000 shapefiles of size less than 5 KB.Should i add them all in one Virtualization layer or can load each of them in individual Virtualization layers.Kindly advice.

Thanks In Anticipation.

[Petar Mladenov]

Hi Sanjay,

We answered these questions in the following forum thread.

http://www.telerik.com/community/forums/how-to-add-asyncshapefilereader-to-mapshapedatavirtualizationsource-at-runtime

Regards,
Petar Mladenov
Telerik