ListView doesn't update UI on data change

Hi,

I'm currently working on a calendar view where you can select a day to see the events of this day in a ListView. My collection holds all events, so I'm using a dataFilter to display only the events of the selected day. Everything works fine until here.

The issue that is driving me crazy this whole morning is that my ListView does not update its ListElements when I select another day. If I call updateUi(); when the day changes, I see that my dataFilter is invoked correctly returning the events of the selected day but they just don't show up in the ListView.

<ListSection id="section" 
    dataCollection="calendar" 
    dataTransform="doTransform" 
    dataFilter="dayFilter"
    dataFunction="updateUi" >
 
    <ListItem template="{template}" time:text="{time}" title:text="{title}" />
 
</ListSection>