Indeed, splitters behave oddly (even in Qt 4.2 TP1). AFAIR you can fix that with QSplitter::setStretchFactor(), but you have to do this in code.
QSplitter docs say:
Which might mean that stretch factors are just ignored. Maybe the Trolls will be able to explain this behavior.The initial distribution of size between the widgets is determined by the initial size of each widget.
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