来自绑定全局列表的Wpf ComboboxEdit

  <dxg:GridColumn.EditTemplate>
      <ControlTemplate>
         <dxe:ComboBoxEdit 
           HorizontalContentAlignment="Left"
           ItemsSource="{Binding HizmetSaglayiciList}"
           SelectedItem="{Binding Hiz_Sag_Id, Mode=TwoWay}"
           ValueMember="Hiz_Sag_Id"
           IsTextEditable="False"
           AllowNullInput="False" 
           AutoComplete="False"                               
           ImmediatePopup="False" 
           EditMode="InplaceActive"/>
       </ControlTemplate>
 </dxg:GridColumn.EditTemplate>
  <dxg:GridColumn.EditTemplate>
      <ControlT