src/ui-kde/qgraphicswidgetitem.cpp

   1 /****************************************************************************
   2 **
   3 ** Copyright (C) 2007-2007 Trolltech ASA. All rights reserved.
   4 **
   5 ** This file is part of the Graphics Widget Items project on Trolltech Labs.
   6 **
   7 ** This file may be used under the terms of the GNU General Public
   8 ** License version 2.0 as published by the Free Software Foundation
   9 ** and appearing in the file LICENSE.GPL included in the packaging of
  10 ** this file.  Please review the following information to ensure GNU
  11 ** General Public Licensing requirements will be met:
  12 ** http://www.trolltech.com/products/qt/opensource.html
  13 **
  14 ** If you are unsure which license is appropriate for your use, please
  15 ** review the following information:
  16 ** http://www.trolltech.com/products/qt/licensing.html or contact the
  17 ** sales department at sales@trolltech.com.
  18 **
  19 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  20 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  21 **
  22 ****************************************************************************/
  23
  24 #include "qgraphicswidgetitem.h"
  25
  26 #include <QtGui/qevent.h>
  27 #include <QtGui/QGraphicsView>
  28
  29 QGraphicsWidgetItem::QGraphicsWidgetItem(QGraphicsWidgetItem *parent)
  30     : QGraphicsItem(parent, 0), embeddedWidget(0), lastActiveView(0)
  31 {
  32     setFlag(ItemIgnoresTransformations);
  33 }
  34
  35 QGraphicsWidgetItem::QGraphicsWidgetItem(QWidget *widget, QGraphicsWidgetItem *parent)
  36     : QGraphicsItem(parent, 0), embeddedWidget(0), lastActiveView(0)
  37 {
  38     setFlag(ItemIgnoresTransformations);
  39     setWidget(widget);
  40 }
  41
  42 QWidget *QGraphicsWidgetItem::widget() const
  43 {
  44     return embeddedWidget;
  45 }
  46
  47 void QGraphicsWidgetItem::setWidget(QWidget *widget)
  48 {
  49     if (embeddedWidget && embeddedWidget->parent() == (QObject *)this) {
  50         embeddedWidget->removeEventFilter(this);
  51         embeddedWidget->hide();
  52         embeddedWidget->setParent(0);
  53     }
  54     embeddedWidget = widget;
  55     if (embeddedWidget) {
  56         embeddedWidget->installEventFilter(this);
  57         adjust();
  58     }
  59 }
  60
  61 QRectF QGraphicsWidgetItem::boundingRect() const
  62 {
  63     return QRectF(0, 0, size.width(), size.height());
  64 }
  65
  66 void QGraphicsWidgetItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
  67 {
  68     adjust();
  69 }
  70
  71 int QGraphicsWidgetItem::type() const
  72 {
  73     return Type;
  74 }
  75
  76 bool QGraphicsWidgetItem::eventFilter(QObject *watched, QEvent *event)
  77 {
  78     // Adjust the item when it's reparented or resized.
  79     if (watched == embeddedWidget) {
  80         switch (event->type()) {
  81         case QEvent::Resize:
  82         case QEvent::ParentChange:
  83             adjust();
  84             break;
  85         default:
  86             break;
  87         }
  88     }
  89
  90     // Adjust the item when the mouse enters or leaves a scene.
  91     if (watched == scene()) {
  92         switch (event->type()) {
  93         case QEvent::Enter:
  94         case QEvent::Leave:
  95             adjust();
  96             break;
  97         default:
  98             break;
  99         }
 100     }
 101
 102     return QObject::eventFilter(watched, event);
 103 }
 104
 105 QVariant QGraphicsWidgetItem::itemChange(GraphicsItemChange change, const QVariant &value)
 106 {
 107     if (change == ItemSceneChange) {
 108         // Update the scene event filter as the item moves to a new scene.
 109         if (QGraphicsScene *oldScene = scene())
 110             oldScene->removeEventFilter(this);
 111         if (QGraphicsScene *newScene = qVariantValue<QGraphicsScene *>(value))
 112             newScene->installEventFilter(this);
 113     }
 114     return QGraphicsItem::itemChange(change, value);
 115 }
 116
 117 void QGraphicsWidgetItem::adjust()
 118 {
 119     QGraphicsScene *scene = this->scene();
 120     if (!scene || !embeddedWidget)
 121         return;
 122
 123     // Update the graphics item's geometry if the widget's geometry has
 124     // changed.
 125     if (embeddedWidget->size() != size) {
 126         prepareGeometryChange();
 127         size = embeddedWidget->size();
 128     }
 129
 130     // Find the active view if there's no active view, use the last known
 131     // active view.
 132     QList<QGraphicsView *> views = scene->views();
 133     QGraphicsView *activeView = 0;
 134     if (views.size() == 1) {
 135         activeView = views.first();
 136     } else {
 137         foreach (QGraphicsView *view, scene->views()) {
 138             if (view->viewport()->underMouse()) {
 139                 activeView = view;
 140                 break;
 141             }
 142         }
 143     }
 144     if (!activeView)
 145         activeView = lastActiveView;
 146     if (!activeView)
 147         return;
 148     lastActiveView = activeView;
 149
 150     // Check if the item is visible in the active view.
 151     QTransform itemTransform = deviceTransform(activeView->viewportTransform());
 152     bool visibleInActiveView = (itemTransform.mapRect(QRect(0, 0, size.width(), size.height())).intersects(activeView->viewport()->rect()));
 153     if (!visibleInActiveView)
 154         return;
 155
 156     // Reparent the widget if necessary.
 157     if (embeddedWidget->parentWidget() != activeView->viewport())
 158         embeddedWidget->setParent(activeView->viewport());
 159
 160     // Move the widget to its new viewport position.
 161     QPoint viewportPos = itemTransform.map(QPointF(0, 0)).toPoint();
 162     embeddedWidget->move(viewportPos);
 163     embeddedWidget->show();
 164 }