MainWindow.xaml

<Window x:Class="HowToCreateLookUpEdit.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525"
        xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
        xmlns:dxe="http://schemas.devexpress.com/winfx/2008/xaml/editors"
        xmlns:dx="http://schemas.devexpress.com/winfx/2008/xaml/core">
    <Grid>
        <dxg:LookUpEdit Name="lookUpEdit1"
                        DisplayMember="ProductName"
                        ValueMember="ID"
                        AutoPopulateColumns="False"
                        AutoComplete="True"
                        IncrementalFiltering="True"
                        ImmediatePopup="True"
                        IsPopupAutoWidth="False"
                        HorizontalAlignment="Center"
                        VerticalAlignment="Top"
                        Width="200" Margin="10">
            <dxg:LookUpEdit.PopupContentTemplate>
                <ControlTemplate>
                    <dxg:GridControl Name="PART_GridControl">
                        <dxg:GridControl.Columns>
                            <dxg:GridColumn FieldName="ProductName"/>
                            <dxg:GridColumn FieldName="UnitPrice"/>
                            <dxg:GridColumn FieldName="Quantity"/>
                        </dxg:GridControl.Columns>
                        <dxg:GridControl.View>
                            <dxg:TableView AutoWidth="True"/>
                        </dxg:GridControl.View>
                    </dxg:GridControl>
                </ControlTemplate>
            </dxg:LookUpEdit.PopupContentTemplate>
        </dxg:LookUpEdit>
    </Grid>
</Window>