summaryrefslogtreecommitdiffstats
path: root/doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp')
-rw-r--r--doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp278
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]
+