From ca60a5a6cffec7ea86f2cab918f64150fdb9f90f Mon Sep 17 00:00:00 2001
From: Marco Martin <notmart@gmail.com>
Date: Fri, 6 Nov 2009 20:20:35 +0000
Subject: [PATCH] convert the function to a qgraphicswidget: sceneeventfilter
 appears to eat events always and in this way i can remove elements from
 dragHandles when they get deleted

svn path=/trunk/KDE/kdelibs/; revision=1045818
---
 widgets/scrollwidget.cpp | 44 ++++++++++++++++++----------------------
 widgets/scrollwidget.h   |  6 +++---
 2 files changed, 23 insertions(+), 27 deletions(-)

diff --git a/widgets/scrollwidget.cpp b/widgets/scrollwidget.cpp
index 63c278afc..23b411048 100644
--- a/widgets/scrollwidget.cpp
+++ b/widgets/scrollwidget.cpp
@@ -213,6 +213,11 @@ public:
                                                 (widget->pos() + delta).toPoint());
     }
 
+    void cleanupDragHandles(QObject *destroyed)
+    {
+        dragHandles.remove(static_cast<QGraphicsWidget *>(destroyed));
+    }
+
     ScrollWidget *q;
     QGraphicsWidget *scrollingWidget;
     QGraphicsWidget *widget;
@@ -228,7 +233,7 @@ public:
     Qt::ScrollBarPolicy horizontalScrollBarPolicy;
     QString styleSheet;
     QRectF rectToBeVisible;
-    QSet<QGraphicsItem *>dragHandles;
+    QSet<QGraphicsWidget *>dragHandles;
     bool dragging;
     int animId;
     static const int borderSize = 4;
@@ -345,9 +350,9 @@ void ScrollWidget::ensureItemVisible(QGraphicsItem *item)
     QTimer::singleShot(0, this, SLOT(makeRectVisible()));
 }
 
-void ScrollWidget::registerAsDragHandle(QGraphicsItem *item)
+void ScrollWidget::registerAsDragHandle(QGraphicsWidget *item)
 {
-    if (!d->widget || !item) {
+    if (!d->widget || !item || d->dragHandles.contains(item)) {
         return;
     }
 
@@ -360,14 +365,15 @@ void ScrollWidget::registerAsDragHandle(QGraphicsItem *item)
         parentOfItem = parentOfItem->parentItem();
     }
 
-    item->installSceneEventFilter(this);
+    connect(item, SIGNAL(destroyed(QObject *)), this, SLOT(cleanupDragHandles(QObject *)));
+    item->installEventFilter(this);
     d->dragHandles.insert(item);
 }
 
-void ScrollWidget::unregisterAsDragHandle(QGraphicsItem *item)
+void ScrollWidget::unregisterAsDragHandle(QGraphicsWidget *item)
 {
     if (item) {
-        item->removeSceneEventFilter(this);
+        item->removeEventFilter(this);
         d->dragHandles.remove(item);
     }
 }
@@ -482,24 +488,6 @@ void ScrollWidget::wheelEvent(QGraphicsSceneWheelEvent *event)
 
 }
 
-bool ScrollWidget::sceneEventFilter(QGraphicsItem *watched, QEvent *event)
-{
-    if (!d->widget && !scene()) {
-        return false;
-    }
-
-    if (d->dragHandles.contains(watched)) {
-        if (event->type() == QEvent::GraphicsSceneMousePress ||
-            event->type() == QEvent::GraphicsSceneMouseMove ||
-            event->type() == QEvent::GraphicsSceneMouseRelease) {
-            if (scene()) {
-                scene()->sendEvent(d->widget, event);
-            }
-        }
-    }
-    return false;
-}
-
 bool ScrollWidget::eventFilter(QObject *watched, QEvent *event)
 {
     if (!d->widget) {
@@ -518,6 +506,14 @@ bool ScrollWidget::eventFilter(QObject *watched, QEvent *event)
         d->verticalScrollBar->setValue(-d->widget->pos().y()/10);
         d->horizontalScrollBar->blockSignals(false);
         d->verticalScrollBar->blockSignals(false);
+    } else if (d->dragHandles.contains(static_cast<QGraphicsWidget *>(watched))) {
+        if (event->type() == QEvent::GraphicsSceneMousePress ||
+            event->type() == QEvent::GraphicsSceneMouseMove ||
+            event->type() == QEvent::GraphicsSceneMouseRelease) {
+            if (scene()) {
+                scene()->sendEvent(this, event);
+            }
+        }
     }
 
     return false;
diff --git a/widgets/scrollwidget.h b/widgets/scrollwidget.h
index 37cdf95d6..c6397c509 100644
--- a/widgets/scrollwidget.h
+++ b/widgets/scrollwidget.h
@@ -129,13 +129,13 @@ public:
      *             it's not necessary to call this function.
      * @since 4.4
      */
-    void registerAsDragHandle(QGraphicsItem *item);
+    void registerAsDragHandle(QGraphicsWidget *item);
 
     /**
      * Unregister the given item as drag handle (if it was registered)
      * @since 4.4
      */
-    void unregisterAsDragHandle(QGraphicsItem *item);
+    void unregisterAsDragHandle(QGraphicsWidget *item);
 
     /**
      * The geometry of the viewport.
@@ -191,7 +191,6 @@ protected:
     bool eventFilter(QObject *watched, QEvent *event);
     void focusInEvent(QFocusEvent *event);
     QSizeF sizeHint(Qt::SizeHint which, const QSizeF & constraint) const;
-    bool sceneEventFilter(QGraphicsItem *watched, QEvent *event);
 
 private:
     ScrollWidgetPrivate * const d;
@@ -199,6 +198,7 @@ private:
     Q_PRIVATE_SLOT(d, void verticalScroll(int value))
     Q_PRIVATE_SLOT(d, void horizontalScroll(int value))
     Q_PRIVATE_SLOT(d, void makeRectVisible())
+    Q_PRIVATE_SLOT(d, void cleanupDragHandles(QObject *destroyed))
 };
 
 } // namespace Plasma