Hiding softkeyboard causes refresh?

Question

Hi guys 25 days ago I asked explaination about refreshing of listview withot calling notifyDataSetChanged():

Listview refresh without notifyDataSetChange

Now the question is connected to the last because I noticed that listview doesn't refresh without notify method but only when I press back button to hide softkeyboard. So when I add an item to listview, if I call notifyDataSetChanged() and the softkeyboard is opened I see immediatelly adding result, if I haven't notify and add new item to listview I see adding result only when press back button to hide softkeyboard.

I surfed on internet to understand this behaviour but nothing helped me. Can anyone explain me if hiding softkeyboard causes refresh of something?

My code:

btnAdd.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            // Toast.makeText(getActivity(), txtQuantita.getText(), Toast.LENGTH_LONG).show();
            if (!txtQuantita.getText().toString().equals(""))
            {
                row.setQuantity(Double.parseDouble(txtQuantita.getText().toString()));
                new InsertShopRowAsync(getActivity(), mListFoodsIn, wherehouseAdapter, row, false).execute();
            }

          //InputMethodManager inputMethodManager =  (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
          //inputMethodManager.toggleSoftInput(InputMethodManager.HIDE_IMPLICIT_ONLY, 0);

Async add:

   public InsertShopRowAsync(Context ct, ArrayList<Wherehouse> list, wherehouseAdapter adapter, Wherehouse newRow, boolean updateQuery) {
        mContext = ct;
        mList = list;
        newItem = newRow;
        mAdapter = adapter;
        db = new DBManager(ct);
        queryUpdate = updateQuery;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected Boolean doInBackground(Wherehouse... wherehouses) {


        int index = GetItemAtIndex(newItem);
        if (index > -1){
            //Ho un item uguale, lo aggiorno --> qui aggiorno solo incrementando le qta al contrario della dailymealsfragment dove rimpiazzio direttamente la routine
            mList.get(index).setQuantity( mList.get(index).getQuantity() + newItem.getQuantity());
        }else{
            mList.add(newItem);
        }
        boolean result = db.InsertIntoWherehouse(newItem);

        return result;
    }

    @Override
    protected void onPostExecute(Boolean aLong) {
        super.onPostExecute(aLong);

           //mAdapter.notifyDataSetChanged();

        asyncInsertedResult = aLong;
    }