The follow sample demonstrates initializing the EditorType of a specific field's Settings so that it should use a XamCurrencyEditor. The EditAsType would only need to be initialized if the DataType of the Field differs from how the value should be interpretted. For example, if the control was bound to an xml data source where the schema was not defined and the type was intrepretted as string.
<igDP:XamDataGrid
DataSource="{Binding Source={StaticResource OrdersDataSource}, XPath=Order}">
<igDP:XamDataGrid.FieldLayouts>
<igDP:FieldLayout>
<igDP:FieldLayout.Fields>
<igDP:Field Name="Title" Column="0"/>
<igDP:Field Name="Price" Column="1">
<igDP:Field.Settings>
<igDP:FieldSettings
EditorType="{x:Type igEditors:XamCurrencyEditor}"
EditAsType="{x:Type sys:Decimal}" />
</igDP:Field.Settings>
</igDP:Field>
</igDP:FieldLayout.Fields>
</igDP:FieldLayout>
</igDP:XamDataGrid.FieldLayouts>
</igDP:XamDataGrid>
