sapui5 smartfilterbar filter positioning

In my app i have smart filter bar with smart filters. I'm using annotations on front end (no possibility to generate it from back-end, unfortunately).

I also have 2 custom filters that are defined in my xml view

Now, i'm struggling an issue with positioning of the filters in right order (i need search bar, which is my custom field to be the first). I use index property, but that doesn't seem to be working.

Can somebody please help me on this?