c# - Add items to wpf DataGrid in design mode -

i have kind of complex type (with nested class)

namespace restore {     public class item     {         public string title { get; set; }         public imagesource image { get; set; }     }      public class itemsummary     {         public imagesource status { get; set; }         public item item { get; set; }         public string description { get; set; }     } } 

and xaml

<window x:class="restore.mainwindow"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         xmlns:local="clr-namespace:restore"      <window.resources>         <bitmapimage x:key="error" urisource="../../images/error.png" />     </window.resources>      <datagrid>         <datagrid.columns>             <datagridtemplatecolumn header="status" width="45" >                 <datagridtemplatecolumn.celltemplate>                     <datatemplate>                         <image source="{binding status}" width="16" height="16" />                     </datatemplate>                 </datagridtemplatecolumn.celltemplate>             </datagridtemplatecolumn>             <datagridtemplatecolumn header="object" width="*">                 <datagridtemplatecolumn.celltemplate>                     <datatemplate>                         <stackpanel orientation="horizontal">                             <image source="{binding item.image}" width="16" height="16" />                             <textblock text="{binding item.title}" />                         </stackpanel>                     </datatemplate>                 </datagridtemplatecolumn.celltemplate>             </datagridtemplatecolumn>             <datagridtextcolumn header="description" width="*" binding="{binding description}" />         </datagrid.columns>         <local:itemsummary item="{???}" status="{staticresource error}" description="1 item" />         <local:itemsummary item="{???}" status="{staticresource success}" description="2 item" />         <local:itemsummary item="{???}" status="{staticresource warning}" description="3 item" />      </datagrid> </window> 

i don't know how set item value item="{???}"