Widgets/GraphicsView examples: cleanup

Cleanup GraphicsView examples with the help of clang-tidy
 - modernize-use-nullptr
 - modernize-use-default-member-init
 - modernize-use-override.IgnoreDestructors
 - Some QList -> QVector changes
 - use nullptr
 - use normalized includes, remove unused includes
 - fix style

Change-Id: I79347e55bfde52f6ae7749cc7093fbd442044020
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 11 insertions, 3 deletions

diff --git a/examples/widgets/graphicsview/dragdroprobot/coloritem.cpp b/examples/widgets/graphicsview/dragdroprobot/coloritem.cpp
index 262e18a317..23fb5fda50 100644
--- a/examples/widgets/graphicsview/dragdroprobot/coloritem.cpp
+++ b/examples/widgets/graphicsview/dragdroprobot/coloritem.cpp
@@ -48,10 +48,18 @@
 **
 ****************************************************************************/
 
-#include <QtWidgets>
-
 #include "coloritem.h"
 
+#include <QApplication>
+#include <QBitmap>
+#include <QCursor>
+#include <QDrag>
+#include <QGraphicsSceneMouseEvent>
+#include <QMimeData>
+#include <QPainter>
+#include <QRandomGenerator>
+#include <QWidget>
+
 //! [0]
 ColorItem::ColorItem()
     : color(QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256), QRandomGenerator::global()->bounded(256))
@@ -128,7 +136,7 @@ void ColorItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
         QPainter painter(&pixmap);
         painter.translate(15, 15);
         painter.setRenderHint(QPainter::Antialiasing);
-        paint(&painter, 0, 0);
+        paint(&painter, nullptr, nullptr);
         painter.end();
 
         pixmap.setMask(pixmap.createHeuristicMask());