1 files changed, 51 insertions, 54 deletions

diff --git a/src/gui/kernel/qt_cocoa_helpers_mac.mm b/src/gui/kernel/qt_cocoa_helpers_mac.mm
index ddbf53f..c8132e8 100644
--- a/src/gui/kernel/qt_cocoa_helpers_mac.mm
+++ b/src/gui/kernel/qt_cocoa_helpers_mac.mm
@@ -1060,30 +1060,26 @@ QWidget *qt_mac_getTargetForMouseEvent(
     returnGlobalPoint = flipPoint([NSEvent mouseLocation]).toPoint();
     QWidget *mouseGrabber = QWidget::mouseGrabber();
     bool buttonDownNotBlockedByModal = qt_button_down && !QApplicationPrivate::isBlockedByModal(qt_button_down);
+    QWidget *popup = QApplication::activePopupWidget();
 
     // Resolve the widget under the mouse:
     QWidget *widgetUnderMouse = 0;
-    if (nativeWidget) {
+    if (popup || qt_button_down || !nativeWidget || !nativeWidget->isVisible()) {
+        // Using QApplication::widgetAt for finding the widget under the mouse
+        // is most safe, since it ignores cocoas own mouse down redirections (which
+        // we need to be prepared for when using nativeWidget as starting point).
+        // (the only exception is for QMacNativeWidget, where QApplication::widgetAt fails).
+        // But it is also slower (I guess), so we try to avoid it and use nativeWidget if we can:
+        widgetUnderMouse = QApplication::widgetAt(returnGlobalPoint);
+    }
+
+    if (!widgetUnderMouse && nativeWidget) {
+        // Entering here should be the common case. We
+        // also handle the QMacNativeWidget fallback case.
         QPoint p = nativeWidget->mapFromGlobal(returnGlobalPoint);
         widgetUnderMouse = nativeWidget->childAt(p);
-        if (!widgetUnderMouse){
-            // Cocoa will redirct mouse event to the current
-            // mouse down widget, which is not what we want for our
-            // widgetUnderMouse assignment. So we need to check
-            // if we are actually inside nativeView:
-            if (nativeWidget->rect().contains(p)) {
-                widgetUnderMouse = nativeWidget;
-            } else {
-                // Ok, fallback to find the widget under mouse ourselves.
-                widgetUnderMouse = QApplication::widgetAt(returnGlobalPoint);
-            }
-        }
-    } else {
-        // Calling QApplication::widgetAt is potentially slow, hence the
-        // reason we avoid it if we can. So supplying a nativeWidget to
-        // this function is mostly an optimization. But at the same time,
-        // calling QApplication::widgetAt fails for QMacNativeWidget...
-        widgetUnderMouse = QApplication::widgetAt(returnGlobalPoint);
+        if (!widgetUnderMouse && nativeWidget->rect().contains(p))
+            widgetUnderMouse = nativeWidget;
     }
 
     if (widgetUnderMouse) {
@@ -1107,23 +1103,27 @@ QWidget *qt_mac_getTargetForMouseEvent(
     if (returnWidgetUnderMouse)
         *returnWidgetUnderMouse = widgetUnderMouse;
 
-    // Resolve the target for the mouse event. Default will be widgetUnderMouse, except
-    // if there is a popup-"grab", mousegrab, or button-down-"grab":
-    QWidget *popup = QApplication::activePopupWidget();
+    // Resolve the target for the mouse event. Default will be
+    // widgetUnderMouse, except if there is a grab (popup/mouse/button-down):
     if (popup && !mouseGrabber) {
-        if (!popup->isAncestorOf(widgetUnderMouse)) {
-            // The popup will always grab the mouse unless the
-            // mouse is over a child, or the user scrolls:
+        // We special case handling of popups, since they have an implicitt mouse grab.
+        QWidget *candidate = buttonDownNotBlockedByModal ? qt_button_down : widgetUnderMouse;
+        if (!popup->isAncestorOf(candidate)) {
+            // INVARIANT: we have a popup, but the candidate is not
+            // in it. But the popup will grab the mouse anyway,
+            // except if the user scrolls:
             if (eventType == QEvent::Wheel)
                 return 0;
             returnLocalPoint = popup->mapFromGlobal(returnGlobalPoint);
             return popup;
-        } else if (popup == widgetUnderMouse) {
+        } else if (popup == candidate) {
+            // INVARIANT: The candidate is the popup itself, and not a child:
             returnLocalPoint = popup->mapFromGlobal(returnGlobalPoint);
             return popup;
         } else {
-            returnLocalPoint = widgetUnderMouse->mapFromGlobal(returnGlobalPoint);
-            return widgetUnderMouse;
+            // INVARIANT: The candidate is a child inside the popup:
+            returnLocalPoint = candidate->mapFromGlobal(returnGlobalPoint);
+            return candidate;
         }
     }
 
@@ -1139,6 +1139,8 @@ QWidget *qt_mac_getTargetForMouseEvent(
     return target;
 }
 
+QPointer<QWidget> qt_last_native_mouse_receiver = 0;
+
 static inline void qt_mac_checkEnterLeaveForNativeWidgets(QWidget *maybeEnterWidget)
 {
     // Dispatch enter/leave for the cases where QApplicationPrivate::sendMouseEvent do
@@ -1149,29 +1151,25 @@ static inline void qt_mac_checkEnterLeaveForNativeWidgets(QWidget *maybeEnterWid
 
     if (qt_button_down || QWidget::mouseGrabber())
         return;
-    if ((maybeEnterWidget == qt_last_mouse_receiver) && qt_last_mouse_receiver)
-        return;
 
+    if ((maybeEnterWidget == qt_last_native_mouse_receiver) && qt_last_native_mouse_receiver)
+        return;
     if (maybeEnterWidget) {
-        if (!qt_last_mouse_receiver) {
+        if (!qt_last_native_mouse_receiver) {
             // case 3
             QApplicationPrivate::dispatchEnterLeave(maybeEnterWidget, 0);
-            qt_last_mouse_receiver = maybeEnterWidget;
-        } else if (qt_last_mouse_receiver->internalWinId() && maybeEnterWidget->internalWinId()) {
+            qt_last_native_mouse_receiver = maybeEnterWidget->internalWinId() ? maybeEnterWidget : maybeEnterWidget->nativeParentWidget();
+        } else if (maybeEnterWidget->internalWinId()) {
             // case 1
-            if (qt_last_mouse_receiver->isVisible()) {
-                QApplicationPrivate::dispatchEnterLeave(maybeEnterWidget, qt_last_mouse_receiver);
-                qt_last_mouse_receiver = maybeEnterWidget;
-            }
+            QApplicationPrivate::dispatchEnterLeave(maybeEnterWidget, qt_last_native_mouse_receiver);
+            qt_last_native_mouse_receiver = maybeEnterWidget->internalWinId() ? maybeEnterWidget : maybeEnterWidget->nativeParentWidget();
         } // else at lest one of the widgets are alien, so enter/leave will be handled in QApplicationPrivate
     } else {
-        if (qt_last_mouse_receiver && qt_last_mouse_receiver->internalWinId()) {
+        if (qt_last_native_mouse_receiver) {
             // case 2
-            QApplicationPrivate::dispatchEnterLeave(0, qt_last_mouse_receiver);
-            // This seems to be the only case where we need to update qt_last_mouse_receiver
-            // from the mac specific code. Otherwise, QApplicationPrivate::sendMouseEvent
-            // will handle it:
+            QApplicationPrivate::dispatchEnterLeave(0, qt_last_native_mouse_receiver);
             qt_last_mouse_receiver = 0;
+            qt_last_native_mouse_receiver = 0;
         }
     }
 }
@@ -1192,16 +1190,14 @@ bool qt_mac_handleMouseEvent(NSEvent *event, QEvent::Type eventType, Qt::MouseBu
     if (!widgetToGetMouse)
         return false;
 
-    if (!nativeWidget) {
-        // Path typically taken for mouse moves (send
-        // directly from [QCocoaWindow sendEvent]
-        if (!widgetUnderMouse)
-            return false;
-        nativeWidget = widgetUnderMouse->internalWinId() ?
-            widgetUnderMouse : widgetUnderMouse->nativeParentWidget();
-        if (!nativeWidget)
-            return false;
-    }
+    // From here on, we let nativeWidget actually be the native widget under widgetUnderMouse. The reason
+    // for this, is that qt_mac_getTargetForMouseEvent will set cocoa's mouse event redirection aside when
+    // determining which widget is under the mouse (in other words, it will usually ignore nativeWidget).
+    // nativeWidget will be used in QApplicationPrivate::sendMouseEvent to correctly dispatch enter/leave events.
+    if (widgetUnderMouse)
+        nativeWidget = widgetUnderMouse->internalWinId() ? widgetUnderMouse : widgetUnderMouse->nativeParentWidget();
+    if (!nativeWidget)
+        return false;
     NSView *view = qt_mac_effectiveview_for(nativeWidget);
 
     // Handle tablet events (if any) first.
@@ -1278,8 +1274,9 @@ bool qt_mac_handleMouseEvent(NSEvent *event, QEvent::Type eventType, Qt::MouseBu
     if (eventType == QEvent::MouseButtonRelease) {
         // A mouse button was released, which means that the implicit grab was
         // released. We therefore need to re-check if should send (delayed) enter leave events:
-        // qt_button_down has now become NULL since the call at the top of the function.
-        widgetToGetMouse = qt_mac_getTargetForMouseEvent(0, QEvent::None, localPoint, globalPoint, nativeWidget, &widgetUnderMouse);
+        // qt_button_down has now become NULL since the call at the top of the function. Also, since
+        // the relase might have closed a window, we dont give the nativeWidget hint
+        qt_mac_getTargetForMouseEvent(0, QEvent::None, localPoint, globalPoint, nativeWidget, &widgetUnderMouse);
         qt_mac_checkEnterLeaveForNativeWidgets(widgetUnderMouse);
     }