DataView is a DataView this is the cause. DataView is the view of data.
With a datasource you can filter order etc then you see the effects on DataView.
this.ddsTerminKonfiguration.DataView.Add is not a valid operation.
http://msdn.microsoft.com/en-us/library/ee707363(v=vs.91).aspx
Basic usage is
<Grid x:Name="LayoutRoot" Background="White">
<riaControls:DomainDataSource x:Name="source" QueryName="GetProductsByColor" AutoLoad="true">
<riaControls:DomainDataSource.DomainContext>
<domain:ProductDomainContext />
</riaControls:DomainDataSource.DomainContext>
<riaControls:DomainDataSource.QueryParameters>
<riaData:Parameter ParameterName="color" Value="Black" />
</riaControls:DomainDataSource.QueryParameters>
</riaControls:DomainDataSource>
<data:DataGrid ItemsSource="{Binding Data, ElementName=source}" />
</Grid>
As you notice it DataGrid bound to Data not DataView.
{Binding Data, ElementName=source}"