Fortunately, I have found it.

<s:DataGroup itemRenderer="ListPostRenderer" verticalCenter="0"
x.normal="0" y.normal="5" x.disabled="0" y.disabled="10" id="dataGroup"
height="205" clipAndEnableScrolling="true">
<s:layout>
<s:VerticalLayout gap.normal="0" paddingTop="10"/>
</s:layout>
</s:DataGroup>