title: QListView in gridmode: auto stretch with fixed items on a row / column
body: <p>I want to make a simple grid with <code>QListView</code>, e.g 3x3, but the <code>gridSize()</code> option in <code>QListView</code> doesn't work that way, it's the width/height of all child widgets in <code>QListView</code>, how should I do that ?</p>