Web Dynpro ALV is not displaying

Hi experts.

As title of this discussion suggests I have a problem with displaying ALV in Web Dynpro. I read many tutorials and everyhing I've done looks ok, but I don't understand why my code isn't working as intended.

1. I've added node GT_PERSONS to ComponentController. In field "Dictionary Structure" i put name of my own structure.

2. I've copied that node to my View (mapping is created).

3. I've created ViewContainerUIElement called "INW_ALL_ITEM" in my View layout and also a button "ShowALV".

4. Here is mine Window Structure:

5. In InterfaceController_Usage node "DATA" is the same type as my node GT_PERSONS and it's mapped with(?) it.

6. I set event to my button, method was created automatically. In this method I put my code (seletcs and other stuff to populate my internal table)

7. Here's the code which in my opinion should bind my data to ALV's node and display it:

DATA lo_nd_item_tab_alv TYPE REF TO if_wd_context_node.

DATA lo_el_item_tab_alv TYPE REF TO if_wd_context_element.

DATA ls_persons TYPE wd_this->element_gt_persons.

lo_nd_item_tab_alv = wd_context->get_child_node( name = wd_this->wdctx_gt_persons ).

lo_nd_item_tab_alv->bind_table( lt_alv_persons ).

wd_this->gt_persons[] = lt_alv_persons[].

Can you please tell me if I am doing something wrong? If you need more info please tell me about and I'll try to provide it ASAP.

Thank you all in advance

Bartłomiej.