This isn't a nice fix but the least evil version of a hack i could come
up. The source of the flickering is: We have a deeply nested structure
of widgets on the project pane. If we call hide() on such a deeply
nested widget, it will activate() it's parent layout synchronously.
That will then post an event (via updateGeometries() ) to its parent
layout that it needs relayouting. Which then will post to its parent
layout the same. And for each LayoutRequested, there's a painting in
between. The fix instead calls activate() up the chain until we are at
the viewport. This immediately relayouts everything. This adds a non
obvoius potentially for breakeage if the widgets are embedded in a
different widget hierarchy. But well, that's life.
This has still a few missing things, but this enough to start getting
some feedback. Missing are non qt projects, a solution for the
runconfiguration, a missing black line between the treeview on top and
the project settings at the bottom. Some flickering with removing/adding
widgets to the QScrollArea and not showing the expanded widget if the
Details button is right at the bottom.
Removing the last project did set startupproject to zero and unloaded
the project. Thus the check that the project for the current item and
the startup project are both null and the same.
