Access iLenght property of binding.filter

Hello experts,

I need to access iLenght property value of binding.filter (see image).

I want to retrieve the number of list item in onInit function (or anyway show it at the end of the page loading). I've already use list.getItems().length() and dont work (return 0), so I found iLength property that get number of filtered items (remark: oList have 4 object and iLenght is 3 because apply offline filter on JSON Model).

Does anyone know how to access iLenght property value?