Mobile app framework 7 > how to display 2nd picker and load serverconnect on 1srt picker changed value

Hi everybody,
How to reload a serverconnect based on previous picker F7 value?
I tryed adding a dmx-show on the second picker when 1rst picket value is not null.
Then I tried a reload SC on-changed.
(I used the same logic on web app with success)

This no works on browser

dmx-on:changed="app.main.f7page.scListModeles.load({idmarque: app.main.f7page.popupCreateMagasin.f7viewCreateMagasin.f7pageCreateMagasin.f7pickerMarques.value},true)"

Thanks for your help