Build placeholders/parameters for HTML element

Hi there,

How can I add an individual placeholder/parameter to my dashboard?

I have tried it already the following way, but it didn't work:

• add a custom parameter "ActualTime" under the components tab:
  Code:

  ---

  function f() {    var Jetzt = new Date();
    return Jetzt.toLocaleString();
}

  ---

• add ${ActualTime} to a HTML element in the layout tab
• in preview the placeholder isn't replaced

Can somebody please help me with this, I didn't find any other forum entries on an similiar issue?

Best
Karsten