getVScrollRange for combobox always return 1

[corentinjaffre]

I wrote a few months ago a function which centers the combobox scroll to the current selection. It seems to be broken right now, because getVScrollRange always returns 1, even if the combobox is full of data with a visible V scrollbar.

I'm doing this: float itemSize = _sender->getVScrollRange() / _sender->getItemCount(); _sender->setVScrollPosition(_sender->getIndexSelected() * itemSize); And it doesn't work anymore.

[Altren]

You are doing integer division, both getVScrollRange and getItemCount return size_t, thus _sender->getVScrollRange() / _sender->getItemCount() return size_t. You should do (float)_sender->getVScrollRange() / _sender->getItemCount()

[Altren]

Also I guess that _sender is ComboBox and it have it's internal scroll (because it have edit area). So you are changing wrong scroll bar. There is _sender->beginToItemSelected(); that makes selected item visible. Unfortunately there is no direct access to the popup list, so to make it centered you would need to call something ugly like _sender->beginToItemAt(_sender->getIndexSelected() - 2)

[corentinjaffre]

OK, that can explain why _sender->getVScrollRange() always return 1. Anyway beginToItemSelected() is good enough for me, so thanks a lot for your information.