[TYPO3-project-formidable] Edit in list using a modalbox, using renderlet:LISTBOX inside the modalbox

[Kontaxis Panagiotis]

Hello!

I tried the new "Edit in list using a modalbox" example.

I used renderlet:TEXT and renderlet:BUTTON inside the modalbox 
successfully but I couldn't use renderlet:LISTBOX inside the modalbox. 
When I added renderlet:LISTBOX, the modalbox didn't appear.

Maybe modalbox supports only renderlet:TEXT and renderlet:BUTTON?

My code of modalbox follows:
<renderlet:MODALBOX name="editbox">
<childs>
<renderlet:TEXT name="title" label="Title" />
<renderlet:LISTBOX name="list_pack" label="Packs List">
<data>
<items>
<item caption="pack1" value="1"/>
<item caption="pack2" value="2"/>
</items>
</data>
</renderlet:LISTBOX>
				
<renderlet:BUTTON name="btnCancel" label="Cancel">
<onclick runat="client" exec="cb1.btnCancel_click()" />
</renderlet:BUTTON>
<renderlet:BUTTON name="btnSave" label="Save and close">
<onclick
	runat="ajax"
	params="editbox.title, editbox.subtitle"
	cache="false"
	exec="cb1.btnSave_click()"
/>
</renderlet:BUTTON>
</childs>
</renderlet:MODALBOX>