Rewrote most of the regular pointer handling.

The old implementation had been hacked on for a while and needed
cleanup. The new code is heavily based on looking at the behavior of
other platforms. It also reuses more of the cross platform code,
which improves the handling of Enter and Leave events.

We also switched to letting Symbian grab the pointer automatically
when pressing down the mouse button, which improves things
considerably compared to doing it ourselves.

Popups should also work a lot better after this fix, since they were
not really handled at all in the old code.

The old code had calls to set the Symbian cursor sprite. This code
has been removed since that code is now being called from within
dispatchEnterLeaveEvents().

In addition, there was code to check whether the up key event had
been left out by the platform. This was solved a bit differently now,
instead putting the code in the section that handles virtual mouse,
since that is where the problem occurs.

Task:     QTBUG-4990
RevBy:    Shane Kearns
AutoTest: N/A, Platform specific code that an autotest cannot catch.
          Lots of manual testing was done on normal examples as well
          drag'n'drop examples and it seemed to work fine.

2 files changed, 94 insertions, 90 deletions

diff --git a/src/gui/kernel/qapplication_s60.cpp b/src/gui/kernel/qapplication_s60.cpp
index ab57c32..27f2644 100644
--- a/src/gui/kernel/qapplication_s60.cpp
+++ b/src/gui/kernel/qapplication_s60.cpp
@@ -361,6 +361,8 @@ void QSymbianControl::ConstructL(bool isWindowOwning, bool desktop)
 
         SetFocusing(true);
         m_longTapDetector = QLongTapTimer::NewL(this);
+
+        DrawableWindow()->SetPointerGrab(ETrue);
     }
 }
 
@@ -472,41 +474,6 @@ void QSymbianControl::HandlePointerEventL(const TPointerEvent& pEvent)
     QT_TRYCATCH_LEAVING(HandlePointerEvent(pEvent));
 }
 
-typedef QPair<QWidget*,QMouseEvent> Event;
-
-/*
- * Helper function called by HandlePointerEvent - separated to keep that function readable
- */
-static void generateEnterLeaveEvents(QList<Event> &events, QWidget *widgetUnderPointer,
-    QPoint globalPos, Qt::MouseButton button, Qt::KeyboardModifiers modifiers)
-{
-    //moved to another widget, create enter and leave events
-    if (S60->lastPointerEventTarget) {
-        QMouseEvent mEventLeave(QEvent::Leave, S60->lastPointerEventTarget->mapFromGlobal(
-            S60->lastCursorPos), S60->lastCursorPos, button, QApplicationPrivate::mouse_buttons,
-            modifiers);
-        events.append(Event(S60->lastPointerEventTarget, mEventLeave));
-    }
-    if (widgetUnderPointer) {
-        QMouseEvent mEventEnter(QEvent::Enter, widgetUnderPointer->mapFromGlobal(globalPos),
-            globalPos, button, QApplicationPrivate::mouse_buttons, modifiers);
-
-        events.append(Event(widgetUnderPointer, mEventEnter));
-#ifndef QT_NO_CURSOR
-        S60->curWin = widgetUnderPointer->effectiveWinId();
-        if (!QApplication::overrideCursor()) {
-#ifndef Q_SYMBIAN_FIXED_POINTER_CURSORS
-            if (S60->brokenPointerCursors)
-                qt_symbian_set_pointer_sprite(widgetUnderPointer->cursor());
-            else
-#endif
-                qt_symbian_setWindowCursor(widgetUnderPointer->cursor(), S60->curWin);
-        }
-#endif
-    }
-}
-
-
 void QSymbianControl::HandlePointerEvent(const TPointerEvent& pEvent)
 {
     QMouseEvent::Type type;
@@ -514,85 +481,77 @@ void QSymbianControl::HandlePointerEvent(const TPointerEvent& pEvent)
     mapS60MouseEventTypeToQt(&type, &button, &pEvent);
     Qt::KeyboardModifiers modifiers = mapToQtModifiers(pEvent.iModifiers);
 
-    if (type == QMouseEvent::None)
-        return;
-
-    // store events for later sending/saving
-    QList<Event > events;
-
     QPoint widgetPos = QPoint(pEvent.iPosition.iX, pEvent.iPosition.iY);
     TPoint controlScreenPos = PositionRelativeToScreen();
     QPoint globalPos = QPoint(controlScreenPos.iX, controlScreenPos.iY) + widgetPos;
+    S60->lastCursorPos = globalPos;
+    S60->lastPointerEventPos = widgetPos;
 
-    // widgets interested in the event
-    QWidget *widgetUnderPointer = qwidget->childAt(widgetPos);
-    if (!widgetUnderPointer)
-        widgetUnderPointer = qwidget; //i.e. this container widget
+    QWidget *mouseGrabber = QWidget::mouseGrabber();
 
-    QWidget *widgetWithMouseGrab = QWidget::mouseGrabber();
+    QWidget *popupWidget = qApp->activePopupWidget();
+    QWidget *popupReceiver = 0;
+    if (popupWidget) {
+        QWidget *popupChild = popupWidget->childAt(popupWidget->mapFromGlobal(globalPos));
+        popupReceiver = popupChild ? popupChild : popupWidget;
+    }
 
-    // handle auto grab of pointer when pressing / releasing
-    if (!widgetWithMouseGrab && type == QEvent::MouseButtonPress) {
-        //if previously auto-grabbed, generate a fake mouse release (platform bug: mouse release event was lost)
-        if (S60->mousePressTarget) {
-            QMouseEvent mEvent(QEvent::MouseButtonRelease, S60->mousePressTarget->mapFromGlobal(globalPos), globalPos,
-                button, QApplicationPrivate::mouse_buttons, modifiers);
-            events.append(Event(S60->mousePressTarget,mEvent));
+    if (mouseGrabber) {
+        if (popupReceiver) {
+            sendMouseEvent(popupReceiver, type, globalPos, button, modifiers);
+        } else {
+            sendMouseEvent(mouseGrabber, type, globalPos, button, modifiers);
         }
-        //auto grab the mouse
-        widgetWithMouseGrab = S60->mousePressTarget = widgetUnderPointer;
-        widgetWithMouseGrab->grabMouse();
-    }
-    if (widgetWithMouseGrab && widgetWithMouseGrab == S60->mousePressTarget && type == QEvent::MouseButtonRelease) {
-        //release the auto grab - note this release event still goes to the autograb widget
-        S60->mousePressTarget = 0;
-        widgetWithMouseGrab->releaseMouse();
+        // No Enter/Leave events in grabbing mode.
+        return;
     }
 
-    QWidget *widgetToReceiveMouseEvent;
-    if (widgetWithMouseGrab)
-        widgetToReceiveMouseEvent = widgetWithMouseGrab;
-    else
-        widgetToReceiveMouseEvent = widgetUnderPointer;
-
-    //queue QEvent::Enter and QEvent::Leave, if the pointer has moved
-    if (widgetUnderPointer != S60->lastPointerEventTarget && (type == QEvent::MouseButtonPress || type == QEvent::MouseButtonDblClick || type == QEvent::MouseMove))
-        generateEnterLeaveEvents(events, widgetUnderPointer, globalPos, button, modifiers);
+    QWidget *widgetUnderPointer = qwidget->childAt(widgetPos);
+    if (!widgetUnderPointer)
+        widgetUnderPointer = qwidget;
 
-    //save global state
-    S60->lastCursorPos = globalPos;
-    S60->lastPointerEventPos = widgetPos;
+    QApplicationPrivate::dispatchEnterLeave(widgetUnderPointer, S60->lastPointerEventTarget);
     S60->lastPointerEventTarget = widgetUnderPointer;
 
+    QWidget *receiver;
+    if (!popupReceiver && S60->mousePressTarget && type != QEvent::MouseButtonPress) {
+        receiver = S60->mousePressTarget;
+        if (type == QEvent::MouseButtonRelease)
+            S60->mousePressTarget = 0;
+    } else {
+        receiver = popupReceiver ? popupReceiver : widgetUnderPointer;
+        if (type == QEvent::MouseButtonPress)
+            S60->mousePressTarget = receiver;
+    }
+
 #if !defined(QT_NO_CURSOR) && !defined(Q_SYMBIAN_FIXED_POINTER_CURSORS)
     if (S60->brokenPointerCursors)
         qt_symbian_move_cursor_sprite();
 #endif
 
-    //queue this event.
-    Q_ASSERT(widgetToReceiveMouseEvent);
-    QMouseEvent mEvent(type, widgetToReceiveMouseEvent->mapFromGlobal(globalPos), globalPos,
+    sendMouseEvent(receiver, type, globalPos, button, modifiers);
+}
+
+void QSymbianControl::sendMouseEvent(
+        QWidget *receiver,
+        QEvent::Type type,
+        const QPoint &globalPos,
+        Qt::MouseButton button,
+        Qt::KeyboardModifiers modifiers)
+{
+    Q_ASSERT(receiver);
+    QMouseEvent mEvent(type, receiver->mapFromGlobal(globalPos), globalPos,
         button, QApplicationPrivate::mouse_buttons, modifiers);
-    events.append(Event(widgetToReceiveMouseEvent,mEvent));
     QEventDispatcherS60 *dispatcher;
     // It is theoretically possible for someone to install a different event dispatcher.
-    if ((dispatcher = qobject_cast<QEventDispatcherS60 *>(widgetToReceiveMouseEvent->d_func()->threadData->eventDispatcher)) != 0) {
+    if ((dispatcher = qobject_cast<QEventDispatcherS60 *>(receiver->d_func()->threadData->eventDispatcher)) != 0) {
         if (dispatcher->excludeUserInputEvents()) {
-            for (int i=0;i < events.count();++i)
-            {
-                Event next = events[i];
-                dispatcher->saveInputEvent(this, next.first, new QMouseEvent(next.second));
-            }
+            dispatcher->saveInputEvent(this, receiver, new QMouseEvent(mEvent));
             return;
         }
     }
 
-    //send events in the queue
-    for (int i=0;i < events.count();++i)
-    {
-        Event next = events[i];
-        sendMouseEvent(next.first, &(next.second));
-    }
+    sendMouseEvent(receiver, &mEvent);
 }
 
 bool QSymbianControl::sendMouseEvent(QWidget *widget, QMouseEvent *mEvent)
@@ -672,27 +631,58 @@ TKeyResponse QSymbianControl::OfferKeyEvent(const TKeyEvent& keyEvent, TEventCod
                         fakeEvent.iType = TPointerEvent::EButton1Up;
                     S60->virtualMouseAccel = 1;
                     S60->virtualMouseLastKey = 0;
+                    switch (keyCode) {
+                    case Qt::Key_Left:
+                        S60->virtualMousePressedKeys &= ~QS60Data::Left;
+                        break;
+                    case Qt::Key_Right:
+                        S60->virtualMousePressedKeys &= ~QS60Data::Right;
+                        break;
+                    case Qt::Key_Up:
+                        S60->virtualMousePressedKeys &= ~QS60Data::Up;
+                        break;
+                    case Qt::Key_Down:
+                        S60->virtualMousePressedKeys &= ~QS60Data::Down;
+                        break;
+                    case Qt::Key_Select:
+                        S60->virtualMousePressedKeys &= ~QS60Data::Select;
+                        break;
+                    }
                 }
                 else if (type == EEventKey) {
                     switch (keyCode) {
                     case Qt::Key_Left:
+                        S60->virtualMousePressedKeys |= QS60Data::Left;
                         x -= S60->virtualMouseAccel;
                         fakeEvent.iType = TPointerEvent::EMove;
                         break;
                     case Qt::Key_Right:
+                        S60->virtualMousePressedKeys |= QS60Data::Right;
                         x += S60->virtualMouseAccel;
                         fakeEvent.iType = TPointerEvent::EMove;
                         break;
                     case Qt::Key_Up:
+                        S60->virtualMousePressedKeys |= QS60Data::Up;
                         y -= S60->virtualMouseAccel;
                         fakeEvent.iType = TPointerEvent::EMove;
                         break;
                     case Qt::Key_Down:
+                        S60->virtualMousePressedKeys |= QS60Data::Down;
                         y += S60->virtualMouseAccel;
                         fakeEvent.iType = TPointerEvent::EMove;
                         break;
                     case Qt::Key_Select:
-                        fakeEvent.iType = TPointerEvent::EButton1Down;
+                        // Platform bug. If you start pressing several keys simultaneously (for
+                        // example for drag'n'drop), Symbian starts producing spurious up and
+                        // down messages for some keys. Therefore, make sure we have a clean slate
+                        // of pressed keys before starting a new button press.
+                        if (S60->virtualMousePressedKeys != 0) {
+                            S60->virtualMousePressedKeys |= QS60Data::Select;
+                            return EKeyWasConsumed;
+                        } else {
+                            S60->virtualMousePressedKeys |= QS60Data::Select;
+                            fakeEvent.iType = TPointerEvent::EButton1Down;
+                        }
                         break;
                     }
                 }
diff --git a/src/gui/kernel/qt_s60_p.h b/src/gui/kernel/qt_s60_p.h
index 08f8bb5..737e9d7 100644
--- a/src/gui/kernel/qt_s60_p.h
+++ b/src/gui/kernel/qt_s60_p.h
@@ -103,6 +103,14 @@ public:
     int defaultDpiY;
     WId curWin;
     int virtualMouseLastKey;
+    enum PressedKeys {
+        Select = 0x1,
+        Right = 0x2,
+        Down = 0x4,
+        Left = 0x8,
+        Up = 0x10
+    };
+    int virtualMousePressedKeys; // of the above type, but avoids casting problems
     int virtualMouseAccel;
     int virtualMouseMaxAccel;
 #ifndef Q_SYMBIAN_FIXED_POINTER_CURSORS
@@ -192,6 +200,12 @@ private:
     TKeyResponse OfferKeyEvent(const TKeyEvent& aKeyEvent,TEventCode aType);
     TKeyResponse sendKeyEvent(QWidget *widget, QKeyEvent *keyEvent);
     bool sendMouseEvent(QWidget *widget, QMouseEvent *mEvent);
+    void sendMouseEvent(
+            QWidget *receiver,
+            QEvent::Type type,
+            const QPoint &globalPos,
+            Qt::MouseButton button,
+            Qt::KeyboardModifiers modifiers);
     void HandleLongTapEventL( const TPoint& aPenEventLocation, const TPoint& aPenEventScreenLocation );
 #ifdef QT_SYMBIAN_SUPPORTS_ADVANCED_POINTER
     void translateAdvancedPointerEvent(const TAdvancedPointerEvent *event);