QAbstractItemView: add virtual itemDelegateForIndex

and obsolete itemDelegate(index), which the new function replaces.

This allows itemviews to override the item delegate per index. The
existing APIs to set delegates for rows and columns doesn't work for
tree views, or other views where the delegate should depend on the
parent index as well.

Adjust all itemview code that accessed the QAIVPrivate's relevant
data structures directly to go through the virtual function.

[ChangeLog][QtWidgets][QAbstractItemView] The
itemDelegate(QModelIndex) member function has been made obsolete,
and has been replaced by a new virtual
itemDelegateForIndex(QModelIndex) member function that can be
overridden to give subclasses control over which item delegate
should be used for an index.

Change-Id: Ib03529c38797386d3a1d4cf3c5646e911d95daf5
Reviewed-by: Samuel Gaist <samuel.gaist@idiap.ch>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Christian Ehrlicher <ch.ehrlicher@gmx.de>

1 files changed, 4 insertions, 3 deletions

diff --git a/src/widgets/itemviews/qlistview.cpp b/src/widgets/itemviews/qlistview.cpp
index 141937da75..721b9aa0d3 100644
--- a/src/widgets/itemviews/qlistview.cpp
+++ b/src/widgets/itemviews/qlistview.cpp
@@ -1083,7 +1083,7 @@ void QListView::paintEvent(QPaintEvent *e)
             previousRow = row;
         }
 
-        d->delegateForIndex(*it)->paint(&painter, option, *it);
+        itemDelegateForIndex(*it)->paint(&painter, option, *it);
     }
 
 #if QT_CONFIG(draganddrop)
@@ -1883,14 +1883,15 @@ QModelIndex QListViewPrivate::closestIndex(const QRect &target,
 
 QSize QListViewPrivate::itemSize(const QStyleOptionViewItem &option, const QModelIndex &index) const
 {
+    Q_Q(const QListView);
     if (!uniformItemSizes) {
-        const QAbstractItemDelegate *delegate = delegateForIndex(index);
+        const QAbstractItemDelegate *delegate = q->itemDelegateForIndex(index);
         return delegate ? delegate->sizeHint(option, index) : QSize();
     }
     if (!cachedItemSize.isValid()) { // the last item is probaly the largest, so we use its size
         int row = model->rowCount(root) - 1;
         QModelIndex sample = model->index(row, column, root);
-        const QAbstractItemDelegate *delegate = delegateForIndex(sample);
+        const QAbstractItemDelegate *delegate = q->itemDelegateForIndex(sample);
         cachedItemSize = delegate ? delegate->sizeHint(option, sample) : QSize();
     }
     return cachedItemSize;