QItemDelegate was superseded since Qt4 by QStyledItemDelegate but it
took until Qt6.7 to remove the last occurrences in qtbase.
- remove unused includes / replace with qabstractitemdelegate.h
- replace references in the documentation with QStyledItemDelegate
- adjust the examples and tests to use QStyledItemDelegate
Pick-to: 6.5
Change-Id: I246755004ce2d01192a726ca0972106c237df0cc
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
(cherry picked from commit 4e8b54eb811f8c6064fd2e937711efe68543087c)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
84f0320209