2 files changed, 53 insertions, 31 deletions

diff --git a/src/gui/kernel/qwidget.cpp b/src/gui/kernel/qwidget.cpp
index ab84a54..492954a 100644
--- a/src/gui/kernel/qwidget.cpp
+++ b/src/gui/kernel/qwidget.cpp
@@ -67,6 +67,7 @@
 # include "qt_mac_p.h"
 # include "qt_cocoa_helpers_mac_p.h"
 # include "qmainwindow.h"
+# include "qtoolbar.h"
 #endif
 #if defined(Q_WS_QWS)
 # include "qwsdisplay_qws.h"
@@ -9716,46 +9717,58 @@ QWidget *QWidget::childAt(const QPoint &p) const
 
 QWidget *QWidgetPrivate::childAt_helper(const QPoint &p, bool ignoreChildrenInDestructor) const
 {
-    Q_Q(const QWidget);
+    if (children.isEmpty())
+        return 0;
+
 #ifdef Q_WS_MAC
+    Q_Q(const QWidget);
+    // Unified tool bars on the Mac require special handling since they live outside
+    // QMainWindow's geometry(). See commit: 35667fd45ada49269a5987c235fdedfc43e92bb8
     bool includeFrame = q->isWindow() && qobject_cast<const QMainWindow *>(q)
                         && static_cast<const QMainWindow *>(q)->unifiedTitleAndToolBarOnMac();
+    if (includeFrame)
+        return childAtRecursiveHelper(p, ignoreChildrenInDestructor, includeFrame);
 #endif
 
-    if (
-#ifdef Q_WS_MAC
-            !includeFrame &&
-#endif
-            !q->rect().contains(p))
+    if (!pointInsideRectAndMask(p))
         return 0;
+    return childAtRecursiveHelper(p, ignoreChildrenInDestructor);
+}
 
-    for (int i = children.size(); i > 0 ;) {
-        --i;
-        QWidget *w = qobject_cast<QWidget *>(children.at(i));
-        if (w && !w->isWindow() && !w->isHidden()
-                && (w->geometry().contains(p)
-#ifdef Q_WS_MAC
-                    || (includeFrame && w->geometry().contains(qt_mac_nativeMapFromParent(w, p)))
+QWidget *QWidgetPrivate::childAtRecursiveHelper(const QPoint &p, bool ignoreChildrenInDestructor, bool includeFrame) const
+{
+#ifndef Q_WS_MAC
+    Q_UNUSED(includeFrame);
 #endif
-               )) {
-            if (ignoreChildrenInDestructor && w->data->in_destructor)
-                continue;
-            if (w->testAttribute(Qt::WA_TransparentForMouseEvents))
-                continue;
-            QPoint childPoint = w->mapFromParent(p);
-#ifdef Q_WS_MAC
-            if (includeFrame && !w->geometry().contains(p))
-                childPoint = qt_mac_nativeMapFromParent(w, p);
-#endif
-            if (QWidget *t = w->d_func()->childAt_helper(childPoint, ignoreChildrenInDestructor))
-                return t;
-            // if WMouseNoMask is set the widget mask is ignored, if
-            // the widget has no mask then the WMouseNoMask flag has no
-            // effect
-            if (w->testAttribute(Qt::WA_MouseNoMask) || w->mask().contains(childPoint)
-                || w->mask().isEmpty())
-                return w;
+    for (int i = children.size() - 1; i >= 0; --i) {
+        QWidget *child = qobject_cast<QWidget *>(children.at(i));
+        if (!child || child->isWindow() || child->isHidden() || child->testAttribute(Qt::WA_TransparentForMouseEvents)
+            || (ignoreChildrenInDestructor && child->data->in_destructor)) {
+            continue;
         }
+
+        // Map the point 'p' from parent coordinates to child coordinates.
+        QPoint childPoint = p;
+#ifdef Q_WS_MAC
+        // 'includeFrame' is true if the child's parent is a top-level QMainWindow with an unified tool bar.
+        // An unified tool bar on the Mac lives outside QMainWindow's geometry(), so a normal
+        // QWidget::mapFromParent won't do the trick.
+        if (includeFrame && qobject_cast<QToolBar *>(child))
+            childPoint = qt_mac_nativeMapFromParent(child, p);
+        else
+#endif
+        childPoint -= child->data->crect.topLeft();
+
+        // Check if the point hits the child.
+        if (!child->d_func()->pointInsideRectAndMask(childPoint))
+            continue;
+
+        // Do the same for the child's descendants.
+        if (QWidget *w = child->d_func()->childAtRecursiveHelper(childPoint, ignoreChildrenInDestructor))
+            return w;
+
+        // We have found our target; namely the child at position 'p'.
+        return child;
     }
     return 0;
 }
diff --git a/src/gui/kernel/qwidget_p.h b/src/gui/kernel/qwidget_p.h
index 49a2dc8..4247c3a 100644
--- a/src/gui/kernel/qwidget_p.h
+++ b/src/gui/kernel/qwidget_p.h
@@ -542,7 +542,9 @@ public:
     bool setMinimumSize_helper(int &minw, int &minh);
     bool setMaximumSize_helper(int &maxw, int &maxh);
     void setConstraints_sys();
+    bool pointInsideRectAndMask(const QPoint &) const;
     QWidget *childAt_helper(const QPoint &, bool) const;
+    QWidget *childAtRecursiveHelper(const QPoint &p, bool, bool includeFrame = false) const;
     void updateGeometry_helper(bool forceUpdate);
 
     void getLayoutItemMargins(int *left, int *top, int *right, int *bottom) const;
@@ -968,6 +970,13 @@ inline void QWidgetPrivate::setSharedPainter(QPainter *painter)
     x->sharedPainter = painter;
 }
 
+inline bool QWidgetPrivate::pointInsideRectAndMask(const QPoint &p) const
+{
+    Q_Q(const QWidget);
+    return q->rect().contains(p) && (!extra || !extra->hasMask || q->testAttribute(Qt::WA_MouseNoMask)
+                                     || extra->mask.contains(p));
+}
+
 inline QWidgetBackingStore *QWidgetPrivate::maybeBackingStore() const
 {
     Q_Q(const QWidget);