title: Do QListView, QTreeView etc. cache and recycle QItemViews or do they load everything at once?
body: <p>I'm coming from iOS development where the basic <code>UITableView</code> and <code>UIScrollView</code> containers cache and then recycle table cells, loading only what will be visible as the user scrolls, in order to conserve memory and improve performance.</p>
  
  <p>I've been trying to find out if the <code>QListView</code>, <code>QTreeView</code>, etc. containers work this way or if they load the entire data source irregardless of what subsection of it will actually be displayed.</p>
  
  <p>I'm not having any issues yet but I am working with an SQLite db with potentially thousands of records, and the <code>QListView</code> will be displaying a thumbnail along with text for each record. So far testing with a few hundred records performance is good but I am wondering if the Qt Model/View approach scales well or if I need to think about managing this myself.</p>