Popup: ensure that "palette" is reevaluated when enabled state changes

When changing the enabled state of a Menu after component completion,
the background would not change. The problem was that
QQuickPopup::paletteChanged() was not being emitted when the enabled
state changed, resulting in QQuickControl::palette() (which
QQuickPopup::palette() forwards calls to via its popupItem) not
being called. QQuickControl::palette() changes the palette's current
color group to QPalette::Disabled when it is disabled, so if it's not
called, the popup's colors won't change.

Fix the issue by adding a virtual enabledChange() function to
QQuickControl, which QQuickPopupItem can override to emit both
QQuickPopup::enabledChanged() (saving a connection in the process)
and QQuickPopup::paletteChanged(). This ensures that bindings to
QQuickPopup::palette are re-evaluated.

The patch adds a virtual instead of just emitting paletteChanged()
in QQuickPopup::setEnabled(), because we also want to be notified
of indirect enabled state changes, such as those coming from
parent items.

Change-Id: Ibdbd05f27b5a74fe731bda9d6698cbf6b8f81785
Fixes: QTBUG-73447
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/quicktemplates2/qquickcontrol_p.h b/src/quicktemplates2/qquickcontrol_p.h
index a38e34f9..3fe20f3b 100644
--- a/src/quicktemplates2/qquickcontrol_p.h
+++ b/src/quicktemplates2/qquickcontrol_p.h
@@ -278,6 +278,7 @@ protected:
     virtual void localeChange(const QLocale &newLocale, const QLocale &oldLocale);
     virtual void paletteChange(const QPalette &newPalette, const QPalette &oldPalette);
     virtual void insetChange(const QMarginsF &newInset, const QMarginsF &oldInset);
+    virtual void enabledChange();
 
 #if QT_CONFIG(accessibility)
     virtual QAccessible::Role accessibleRole() const;