wpf - show submenuitems next to items in a combobox -

i need doing following:

i have combbox , bind value of enum ..

internal enum myproducts     {         producta,         productb,         productc,         productd     }  internal enum productsvalue     {         valuea,         valueb,         valuec,         valued     } 

...

<window.resources> <objectdataprovider x:key="productsobjectdata" methodname="getvalues"                             objecttype="{x:type system:enum}">         <objectdataprovider.methodparameters>             <x:type typename="myproducts"/>         </objectdataprovider.methodparameters>     </objectdataprovider>  <objectdataprovider x:key="valuesobjectdata" methodname="getvalues"                             objecttype="{x:type system:enum}">         <objectdataprovider.methodparameters>             <x:type typename="productsvalue"/>         </objectdataprovider.methodparameters>     </objectdataprovider> </window.resources> 

...

 <combobox itemssource="{binding source={staticresource productsobjectdata}}" horizontalalignment="left" width="160" fontsize="16"> 

now, need show each item in combobox submenu showing values enum productsvalue ..

so, when user clicks on combobox, dropdown of products open , next each item in combobox there should arrow when clicked, show list productvalues .. please check image below .. (it shows user clicked on producta, , choosed valueb) )

any appreciated .. in advance