Initial import from the monolithic Qt.

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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 278 insertions, 0 deletions

diff --git a/doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp b/doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp
new file mode 100644
index 0000000000..c4cf674995
--- /dev/null
+++ b/doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp
@@ -0,0 +1,278 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+**     the names of its contributors may be used to endorse or promote
+**     products derived from this software without specific prior written
+**     permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+class SimpleItem : public QGraphicsItem
+{
+public:
+    QRectF boundingRect() const
+    {
+        qreal penWidth = 1;
+        return QRectF(-10 - penWidth / 2, -10 - penWidth / 2,
+                      20 + penWidth, 20 + penWidth);
+    }
+
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
+               QWidget *widget)
+    {
+        painter->drawRoundedRect(-10, -10, 20, 20, 5, 5);
+    }
+};
+//! [0]
+
+
+//! [1]
+class CustomItem : public QGraphicsItem
+{
+   ...
+   enum { Type = UserType + 1 };
+
+   int type() const
+   {
+       // Enable the use of qgraphicsitem_cast with this item.
+       return Type;
+   }
+   ...
+};
+//! [1]
+
+
+//! [2]
+item->setCursor(Qt::IBeamCursor);
+//! [2]
+
+
+//! [3]
+item->setCursor(Qt::IBeamCursor);
+//! [3]
+
+
+//! [4]
+QGraphicsRectItem rect;
+rect.setPos(100, 100);
+
+rect.sceneTransform().map(QPointF(0, 0));
+// returns QPointF(100, 100);
+
+rect.sceneTransform().inverted().map(QPointF(100, 100));
+// returns QPointF(0, 0);
+//! [4]
+
+
+//! [5]
+QGraphicsRectItem rect;
+rect.setPos(100, 100);
+
+rect.deviceTransform(view->viewportTransform()).map(QPointF(0, 0));
+// returns the item's (0, 0) point in view's viewport coordinates
+
+rect.deviceTransform(view->viewportTransform()).inverted().map(QPointF(100, 100));
+// returns view's viewport's (100, 100) coordinate in item coordinates
+//! [5]
+
+
+//! [6]
+// Rotate an item 45 degrees around (0, 0).
+item->rotate(45);
+
+// Rotate an item 45 degrees around (x, y).
+item->setTransform(QTransform().translate(x, y).rotate(45).translate(-x, -y));
+//! [6]
+
+
+//! [7]
+// Scale an item by 3x2 from its origin
+item->scale(3, 2);
+
+// Scale an item by 3x2 from (x, y)
+item->setTransform(QTransform().translate(x, y).scale(3, 2).translate(-x, -y));
+//! [7]
+
+
+//! [8]
+QRectF CircleItem::boundingRect() const
+{
+    qreal penWidth = 1;
+    return QRectF(-radius - penWidth / 2, -radius - penWidth / 2,
+                  diameter + penWidth, diameter + penWidth);
+}
+//! [8]
+
+
+//! [9]
+QPainterPath RoundItem::shape() const
+{
+    QPainterPath path;
+    path.addEllipse(boundingRect());
+    return path;
+}
+//! [9]
+
+
+//! [10]
+void RoundRectItem::paint(QPainter *painter,
+                          const QStyleOptionGraphicsItem *option,
+                          QWidget *widget)
+{
+    painter->drawRoundedRect(-10, -10, 20, 20, 5, 5);
+}
+//! [10]
+
+
+//! [11]
+static const int ObjectName = 0;
+
+QGraphicsItem *item = scene.itemAt(100, 50);
+if (item->data(ObjectName).toString().isEmpty()) {
+    if (qgraphicsitem_cast<ButtonItem *>(item))
+        item->setData(ObjectName, "Button");
+}
+//! [11]
+
+
+//! [12]
+QGraphicsScene scene;
+QGraphicsEllipseItem *ellipse = scene.addEllipse(QRectF(-10, -10, 20, 20));
+QGraphicsLineItem *line = scene.addLine(QLineF(-10, -10, 20, 20));
+
+line->installSceneEventFilter(ellipse);
+// line's events are filtered by ellipse's sceneEventFilter() function.
+
+ellipse->installSceneEventFilter(line);
+// ellipse's events are filtered by line's sceneEventFilter() function.
+//! [12]
+
+
+//! [13]
+void CustomItem::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
+{
+    QMenu menu;
+    QAction *removeAction = menu.addAction("Remove");
+    QAction *markAction = menu.addAction("Mark");
+    QAction *selectedAction = menu.exec(event->screenPos());
+    // ...
+}
+//! [13]
+
+
+//! [14]
+CustomItem::CustomItem()
+{
+    setAcceptDrops(true);
+    ...
+}
+
+void CustomItem::dragEnterEvent(QGraphicsSceneDragDropEvent *event)
+{
+    event->setAccepted(event->mimeData()->hasFormat("text/plain"));
+}
+//! [14]
+
+
+//! [15]
+QVariant Component::itemChange(GraphicsItemChange change, const QVariant &value)
+{
+    if (change == ItemPositionChange && scene()) {
+        // value is the new position.
+        QPointF newPos = value.toPointF();
+        QRectF rect = scene()->sceneRect();
+        if (!rect.contains(newPos)) {
+            // Keep the item inside the scene rect.
+            newPos.setX(qMin(rect.right(), qMax(newPos.x(), rect.left())));
+            newPos.setY(qMin(rect.bottom(), qMax(newPos.y(), rect.top())));
+            return newPos;
+        }
+    }
+    return QGraphicsItem::itemChange(change, value);
+}
+//! [15]
+
+
+//! [16]
+void CircleItem::setRadius(qreal newRadius)
+{
+    if (radius != newRadius) {
+        prepareGeometryChange();
+        radius = newRadius;
+    }
+}
+//! [16]
+
+
+//! [17]
+// Group all selected items together
+QGraphicsItemGroup *group = scene->createItemGroup(scene->selecteditems());
+
+// Destroy the group, and delete the group item
+scene->destroyItemGroup(group);
+//! [17]
+
+
+//! [QGraphicsItem type]
+class CustomItem : public QGraphicsItem
+{
+   ...
+   enum { Type = UserType + 1 };
+
+   int type() const
+   {
+       // Enable the use of qgraphicsitem_cast with this item.
+       return Type;
+   }
+   ...
+};
+//! [QGraphicsItem type]
+
+//! [18]
+class QGraphicsPathItem : public QAbstractGraphicsShapeItem
+{
+ public:
+  enum { Type = 2 };
+    int type() const { return Type; }
+  ...
+};
+//! [18]
+
+//! [19]
+QTransform xform = item->deviceTransform(view->viewportTransform());
+QRect deviceRect = xform.mapRect(rect).toAlignedRect();
+view->viewport()->scroll(dx, dy, deviceRect);
+//! [19]
+