Reserve a virtual method for use with a feature in Qt 5.1.

The view will query the delegate for roles which are relevant to
the particular delegate. For unrelated roles, the delegate
will not have to repaint when the data changes.

Change-Id: If8f1ba4c2bce7dbcf70de344b984aea1deca0edd
Reviewed-by: Thorbjørn Lund Martsum <tmartsum@gmail.com>
Reviewed-by: David Faure <faure@kde.org>

2 files changed, 12 insertions, 0 deletions

diff --git a/src/widgets/itemviews/qabstractitemdelegate.cpp b/src/widgets/itemviews/qabstractitemdelegate.cpp
index ecba3e238f..125beab91b 100644
--- a/src/widgets/itemviews/qabstractitemdelegate.cpp
+++ b/src/widgets/itemviews/qabstractitemdelegate.cpp
@@ -402,6 +402,16 @@ bool QAbstractItemDelegate::helpEvent(QHelpEvent *event,
     return false;
 }
 
+/*!
+    \internal
+
+    This virtual method is reserved and will be used in Qt 5.1.
+*/
+QSet<int> QAbstractItemDelegate::paintingRoles() const
+{
+    return QSet<int>();
+}
+
 QT_END_NAMESPACE
 
 #endif // QT_NO_ITEMVIEWS
diff --git a/src/widgets/itemviews/qabstractitemdelegate.h b/src/widgets/itemviews/qabstractitemdelegate.h
index 2c51dfcac8..89aa1915f6 100644
--- a/src/widgets/itemviews/qabstractitemdelegate.h
+++ b/src/widgets/itemviews/qabstractitemdelegate.h
@@ -114,6 +114,8 @@ public:
                            const QStyleOptionViewItem &option,
                            const QModelIndex &index);
 
+    virtual QSet<int> paintingRoles() const;
+
 Q_SIGNALS:
     void commitData(QWidget *editor);
     void closeEditor(QWidget *editor, QAbstractItemDelegate::EndEditHint hint = NoHint);