Pre-Filter not working

[Håkan]

Hi!

I have a GridView that I want to pre-filter with checkboxes.
I have read a blog about this here
http://blogs.telerik.com/xamlteam/posts/09-11-27/pre-filtering-radgridview-for-silverlight.aspx
with the following code:

ColumnFilterDescriptor countryColumnFilter = new ColumnFilterDescriptor((IDataFieldDescriptor)this.playersGrid.Columns[2]);
countryColumnFilter.DistinctFilter.DistinctValues.Add("England");
countryColumnFilter.DistinctFilter.DistinctValues.Add("Spain");
this.playersGrid.FilterDescriptors.Add(countryColumnFilter);

The problem is that I get an error saying that "Cannot create an instance of the abstract class or interface "Telerik.Windows.Controls.GridView.ColumnFilterDescriptor".

Its pretty old code so I guess this has changed, but how do I do to make it work now?
I use the last Silverlight 4 version.

Regards,
Håkan

[Yoan]

Hello Håkan,

Actually, the mentioned forum post is quite old. Please check the following code snippet which demonstrates how to add ColumnFilterDescriptor:

Telerik.Windows.Controls.GridViewColumn countryColumn = this.clubsGrid.Columns["Name"];
           Telerik.Windows.Controls.GridView.IColumnFilterDescriptor countryFilter = countryColumn.ColumnFilterDescriptor;
           countryFilter.SuspendNotifications();

           // This is the same as the end user selecting a distinct value through the UI.
           countryFilter.DistinctFilter.AddDistinctValue("Arsenal");
           countryFilter.DistinctFilter.AddDistinctValue("Spain");
           countryFilter.DistinctFilter.AddDistinctValue("Uzbekistan");
           countryFilter.DistinctFilter.AddDistinctValue("Netherlands");
           countryFilter.DistinctFilter.AddDistinctValue("Austria");
           countryFilter.DistinctFilter.AddDistinctValue("Finland");
           countryFilter.DistinctFilter.AddDistinctValue("Pakistan");

           // Resume the notifications to force the data engine to update the filter.
           countryFilter.ResumeNotifications();

I strongly recommend you to take a look at this help article as well.

As a side note I must mention that the support for WPF 3.5 and Silverlight 4 has been discontinued as of Q3 2012. You can check this blog post for more information.



Regards,
Yoan
Telerik

[Håkan]

Thanks Yoan!

That worked much better for me.

Regards,
Håkan