Hi,
In RadGridView on click "Click Here to Add New Item" is not adding new row to the RadGridView. It is designed with the property as below
<telerik:RadGridView Name="radGridSizeDetails" Grid.Row="1"
ShowGroupPanel="False" AutoExpandGroups="True" ShowGroupFooters="False"
ShowColumnFooters="True" CanUserSortColumns="True" ShowColumnHeaders="True"
AutoGenerateColumns="False"
CanUserInsertRows="True"
NewRowPosition="Top"
GroupRenderMode="Flat"
ShowColumnSortIndexes="True"
ItemsSource="{Binding SizeDetailsList}"
SelectionMode="Single"
RowIndicatorVisibility="Visible"
VerticalAlignment="Stretch"
IsReadOnly="False" AddingNewDataItem="radGridSizeDetails_AddingNewDataItem">
Let me know if I miss anything.
Thanks
Dilip