The layouting was becoming too complex to maintain and to introduce
new features. Was even buggy, the fuzzer was constantly finding
bugs, which took hours to workaround.
Problem with the old layout engine is that there was a catch 22, between
Items driving the separators, and separators driving the anchors.
The new layout is much simpler, both in implementation and conceptually.
There's simply a recursive hierarchy of Item elements. An Item can either
have a QWidget to show, or be a ItemContainer, which contains Item children,
and so forth. Each ItemContainer is either vertical or horizontal. That's enough
to represent the "nested multi-splitter" concept which KDDW uses.
After each item insertion/deletion/resize, the separators are regenerated. They
are essentially dumb now.
TODO:
- Separators are drawn, but are not interactive yet
- There's 5 tests failing
- LayoutSaver scalling functionality
Each subset is identified by its "affinity name".
See DockWidget/MainWindow setAffinityName property.
Patch contributed by Andras Mantia, I've changed it to deal in
terms of affinity names instead of unique names.
After a restore with relative sizes the items might not be on a pixel
perfect position regarding to their anchors. Make sure they are after
the restore is complete.
Silenced a false-positive warning about anchor visibility.
It was invisible because we're within a main window show()
It will be checked by the unit-tests and fuzzer anyway. No need to
do it in production.
