[Development] Multi-Selection behavior of item views breaks drag'n'drop UX - options

[Volker Hilsheimer]

Hey Widget fans,

I need your opinions on https://bugreports.qt.io/browse/QTBUG-59888

The UX resulting from our (strange) choice to trigger selection changes on mouse press rather than mouse release is indeed quite horrible, as explained in the ticket.

The options to fix that seem to be:

1) change the default behavior - always change selection on mouse release
2) change the default behavior if drag (as per dragDropMode)
3) make the "selection trigger" a property

None of those options would IMHO result in a change that qualifies for stable branches. I’ve for now implemented option 3. This introduces new API, so if we agree that this is the way to go then it would ideally be merged before 6.2 feature freeze next Friday.

https://codereview.qt-project.org/c/qt/qtbase/+/351595

However, the possible property values seem oddly specific to this problem, and give that this is a 6.2 only change anyway, perhaps it would be best to simply change the default, which would then also make Qt matching native UIs better (ie Windows Explorer or macOS Finder)?

Cheers,
Volker