Ensure a hierarchy of menus fade out together.

On Mac OS X, when you have a large hierarchies of menus and you select
the item at the end of the hierarchy. It will flash and then the rest
will fade out at the same time. Qt would do a phased approach which was
what no one expected. Introduce a QMacWindowFader class that can hold an
arbitrary number of qwidgets and then on command fade them all down
pased on the set duration. The API is a bit clumsy but is prefect for
this internal API.

Task-#: 251700
Reviewed-by: Richard Moe Gustavsen

2 files changed, 27 insertions, 15 deletions

diff --git a/src/gui/widgets/qmenu.cpp b/src/gui/widgets/qmenu.cpp
index 3004841..50100af 100644
--- a/src/gui/widgets/qmenu.cpp
+++ b/src/gui/widgets/qmenu.cpp
@@ -398,9 +398,12 @@ QRect QMenuPrivate::actionRect(QAction *act) const
     return ret;
 }
 
+static const float MenuFadeTimeInSec = 0.150;
+
 void QMenuPrivate::hideUpToMenuBar()
 {
     Q_Q(QMenu);
+    bool fadeMenus = q->style()->styleHint(QStyle::SH_Menu_FadeOutOnHide);
     if (!tornoff) {
         QWidget *caused = causedPopup.widget;
         hideMenu(q); //hide after getting causedPopup
@@ -415,8 +418,9 @@ void QMenuPrivate::hideUpToMenuBar()
             if (QMenu *m = qobject_cast<QMenu*>(caused)) {
                 caused = m->d_func()->causedPopup.widget;
                 if (!m->d_func()->tornoff)
-                    hideMenu(m);
-                m->d_func()->setCurrentAction(0);
+                    hideMenu(m, fadeMenus);
+                if (!fadeMenus) // Mac doesn't clear the action until after hidden.
+                    m->d_func()->setCurrentAction(0);
             } else {
 #ifndef QT_NO_TOOLBUTTON
                 if (qobject_cast<QToolButton*>(caused) == 0)
@@ -425,26 +429,32 @@ void QMenuPrivate::hideUpToMenuBar()
                 caused = 0;
             }
         }
+#if defined(Q_WS_MAC)
+        if (fadeMenus) {
+            QEventLoop eventLoop;
+            QTimer::singleShot(int(MenuFadeTimeInSec * 1000), &eventLoop, SLOT(quit()));
+            QMacWindowFader::currentFader()->performFade();
+            eventLoop.exec();
+        }
+#endif
     }
     setCurrentAction(0);
 }
 
-void QMenuPrivate::hideMenu(QMenu *menu)
+void QMenuPrivate::hideMenu(QMenu *menu, bool justRegister)
 {
     if (!menu)
         return;
-
 #if !defined(QT_NO_EFFECTS)
     menu->blockSignals(true);
     aboutToHide = true;
     // Flash item which is about to trigger (if any).
     if (menu->style()->styleHint(QStyle::SH_Menu_FlashTriggeredItem)
-        && currentAction && currentAction == actionAboutToTrigger) {
-
+        && currentAction && currentAction == actionAboutToTrigger
+        && menu->actions().contains(currentAction)) {
         QEventLoop eventLoop;
         QAction *activeAction = currentAction;
 
-        // Deselect and wait 60 ms.
         menu->setActiveAction(0);
         QTimer::singleShot(60, &eventLoop, SLOT(quit()));
         eventLoop.exec();
@@ -458,22 +468,24 @@ void QMenuPrivate::hideMenu(QMenu *menu)
     // Fade out.
     if (menu->style()->styleHint(QStyle::SH_Menu_FadeOutOnHide)) {
         // ### Qt 4.4:
-        // Should be something like: q->transitionWindow(Qt::FadeOutTransition, 150);
+        // Should be something like: q->transitionWindow(Qt::FadeOutTransition, MenuFadeTimeInSec);
         // Hopefully we'll integrate qt/research/windowtransitions into main before 4.4.
         // Talk to Richard, Trenton or Bjoern.
 #if defined(Q_WS_MAC)
-		macWindowFade(qt_mac_window_for(menu));		// FIXME - what is the default duration for view animations
+        if (justRegister) {
+            QMacWindowFader::currentFader()->setFadeDuration(MenuFadeTimeInSec);
+            QMacWindowFader::currentFader()->registerWindowToFade(menu);
+        } else {
+            macWindowFade(qt_mac_window_for(menu), MenuFadeTimeInSec);
+        }
 
-        // Wait for the transition to complete.
-		QEventLoop eventLoop;
-        QTimer::singleShot(150, &eventLoop, SLOT(quit()));
-        eventLoop.exec();
 #endif // Q_WS_MAC
     }
     aboutToHide = false;
     menu->blockSignals(false);
 #endif // QT_NO_EFFECTS
-    menu->hide();
+    if (!justRegister)
+        menu->hide();
 }
 
 void QMenuPrivate::popupAction(QAction *action, int delay, bool activateFirst)
diff --git a/src/gui/widgets/qmenu_p.h b/src/gui/widgets/qmenu_p.h
index edfeee7..9654126 100644
--- a/src/gui/widgets/qmenu_p.h
+++ b/src/gui/widgets/qmenu_p.h
@@ -220,7 +220,7 @@ public:
     virtual QList<QPointer<QWidget> > calcCausedStack() const;
     QMenuCaused causedPopup;
     void hideUpToMenuBar();
-    void hideMenu(QMenu *menu);
+    void hideMenu(QMenu *menu, bool delay = true);
 
     //index mappings
     inline QAction *actionAt(int i) const { return q_func()->actions().at(i); }