Status symbol and button in header content

Hey,

I wanna show a status symbol in the head of my master list. I have this piece of code:

        <semantic:customHeaderContent>
            <Button id="flushButton" icon="sap-icon://synchronize" press=""/>
            <ObjectStatus id="synchronizedStatus" visible="true" state="Error" icon="sap-icon://alert"/>
        </semantic:customHeaderContent>

But there is only one UI element showed, the button. When I change the order, only the status symbol is shown. How can I establish that both UI elements are shown?

Thanks for your help and best regards,

David