Since to fill an xCLV you use a function that returns you a Panel-B4XView (unless you use AddTextItem), the first time you call it, place this Panel above the xCLV. Obviously you will have to change the value of the views contained in it in case of changes to the items of the xCLV.
Title items are added to the list. A Panel is set above the list. The panel shows the current title when the top visible item is not a title item. It works by checking for the top item type. If it is a title item then the panel is hidden, otherwise the panel is shown with the current title...