QMenu: show shortcuts in context menus by default

Change c2c3452ba introduced a new API in Qt to let QPA inform
whether or not shortcuts should be shown in context menus. This
was set to false by default, since by observation, this seemed to
be the most common behavior across platforms. The problem
is that it left no way for the application to override it; The
attribute Qt::AA_DontShowShortcutsInContextMenus simply doesn't work
when shortcuts are always off. And for some application, showing
shortcuts is not just a matter of look-and-feel, but also important
information to be able to use the application the way intended.

This patch reverts the behavior back to how it was in Qt-5.9, where
shortcuts where shown by default (except on macOS where we still keep
them off). It's no so much because the "always off" logic is wrong, but
because there is no (easy) way/work-around for an app developer to switch
them back on (until Qt-5.13, where a new API is introduced to fix the
situation: b1a9a77). And this lack of API can be a show-stopper for some
when upgrading from e.g 5.9 LTS to 5.12 LTS.

This downside of this patch, OTOH, is that it can cause more
change that what is normally wanted in a patch release. But out of
two evils, this is the best option. Those that wan't to hide shortcuts
can set AA_DontShowShortcutsInContextMenus to true, which now will
work.

[ChangeLog][QtWidgets][QMenu] Shortcuts are again shown by default
in context menus, except on macOS. They can be forced off by
setting AA_DontShowShortcutsInContextMenus to true.

Fixes: QTBUG-69452
Change-Id: Ibcc371395944ac5b19b1d20889940da271bf73d5
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@qt.io>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoaintegration.mm b/src/plugins/platforms/cocoa/qcocoaintegration.mm
index fb3d05d3e4..cbbf6b115e 100644
--- a/src/plugins/platforms/cocoa/qcocoaintegration.mm
+++ b/src/plugins/platforms/cocoa/qcocoaintegration.mm
@@ -490,8 +490,13 @@ QCocoaServices *QCocoaIntegration::services() const
 
 QVariant QCocoaIntegration::styleHint(StyleHint hint) const
 {
-    if (hint == QPlatformIntegration::FontSmoothingGamma)
+    switch (hint) {
+    case FontSmoothingGamma:
         return QCoreTextFontEngine::fontSmoothingGamma();
+    case ShowShortcutsInContextMenus:
+        return QVariant(false);
+    default: break;
+    }
 
     return QPlatformIntegration::styleHint(hint);
 }