Add QQuickMenuPrivate::setParentMenu()

To help propagating the cascade-property automatically, instead of
doing it manually in openSubMenu() that we're trying to get rid of.

Change-Id: I3a3d59cafccc85d6affc325eb60e717e22b8f812
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

3 files changed, 31 insertions, 6 deletions

diff --git a/src/quicktemplates2/qquickmenu.cpp b/src/quicktemplates2/qquickmenu.cpp
index ce10b612..bc19a707 100644
--- a/src/quicktemplates2/qquickmenu.cpp
+++ b/src/quicktemplates2/qquickmenu.cpp
@@ -215,7 +215,7 @@ void QQuickMenuPrivate::insertItem(int index, QQuickItem *item)
         Q_Q(QQuickMenu);
         QQuickMenuItemPrivate::get(menuItem)->setMenu(q);
         if (QQuickMenu *subMenu = menuItem->subMenu())
-            QQuickMenuPrivate::get(subMenu)->parentMenu = q;
+            QQuickMenuPrivate::get(subMenu)->setParentMenu(q);
         QObjectPrivate::connect(menuItem, &QQuickMenuItem::triggered, this, &QQuickMenuPrivate::onItemTriggered);
         QObjectPrivate::connect(menuItem, &QQuickItem::activeFocusChanged, this, &QQuickMenuPrivate::onItemActiveFocusChanged);
         QObjectPrivate::connect(menuItem, &QQuickControl::hoveredChanged, this, &QQuickMenuPrivate::onItemHovered);
@@ -239,7 +239,7 @@ void QQuickMenuPrivate::removeItem(int index, QQuickItem *item)
     if (menuItem) {
         QQuickMenuItemPrivate::get(menuItem)->setMenu(nullptr);
         if (QQuickMenu *subMenu = menuItem->subMenu())
-            QQuickMenuPrivate::get(subMenu)->parentMenu = nullptr;
+            QQuickMenuPrivate::get(subMenu)->setParentMenu(nullptr);
         QObjectPrivate::disconnect(menuItem, &QQuickMenuItem::triggered, this, &QQuickMenuPrivate::onItemTriggered);
         QObjectPrivate::disconnect(menuItem, &QQuickItem::activeFocusChanged, this, &QQuickMenuPrivate::onItemActiveFocusChanged);
         QObjectPrivate::disconnect(menuItem, &QQuickControl::hoveredChanged, this, &QQuickMenuPrivate::onItemHovered);
@@ -472,10 +472,24 @@ void QQuickMenuPrivate::openSubMenu(QQuickMenuItem *item, bool activate)
     p->allowHorizontalFlip = cascade;
     if (activate)
         p->setCurrentIndex(0, Qt::PopupFocusReason);
-    subMenu->setCascade(cascade);
     subMenu->open();
 }
 
+void QQuickMenuPrivate::setParentMenu(QQuickMenu *parent)
+{
+    Q_Q(QQuickMenu);
+    if (parentMenu == parent)
+        return;
+
+    if (parentMenu)
+        QObject::disconnect(parentMenu.data(), &QQuickMenu::cascadeChanged, q, &QQuickMenu::setCascade);
+    if (parent)
+        QObject::connect(parent, &QQuickMenu::cascadeChanged, q, &QQuickMenu::setCascade);
+
+    parentMenu = parent;
+    q->resetCascade();
+}
+
 void QQuickMenuPrivate::startHoverTimer()
 {
     Q_Q(QQuickMenu);
@@ -1005,7 +1019,16 @@ void QQuickMenu::setCascade(bool cascade)
     if (d->cascade == cascade)
         return;
     d->cascade = cascade;
-    emit cascadeChanged();
+    emit cascadeChanged(cascade);
+}
+
+void QQuickMenu::resetCascade()
+{
+    Q_D(QQuickMenu);
+    if (d->parentMenu)
+        setCascade(d->parentMenu->cascade());
+    else
+        setCascade(shouldCascade());
 }
 
 /*!
diff --git a/src/quicktemplates2/qquickmenu_p.h b/src/quicktemplates2/qquickmenu_p.h
index 1211172b..9eeeadd6 100644
--- a/src/quicktemplates2/qquickmenu_p.h
+++ b/src/quicktemplates2/qquickmenu_p.h
@@ -66,7 +66,7 @@ class Q_QUICKTEMPLATES2_PRIVATE_EXPORT QQuickMenu : public QQuickPopup
     Q_PROPERTY(QVariant contentModel READ contentModel CONSTANT FINAL)
     Q_PROPERTY(QQmlListProperty<QObject> contentData READ contentData FINAL)
     Q_PROPERTY(QString title READ title WRITE setTitle NOTIFY titleChanged FINAL)
-    Q_PROPERTY(bool cascade READ cascade WRITE setCascade NOTIFY cascadeChanged FINAL REVISION 3)
+    Q_PROPERTY(bool cascade READ cascade WRITE setCascade RESET resetCascade NOTIFY cascadeChanged FINAL REVISION 3)
     Q_PROPERTY(qreal overlap READ overlap WRITE setOverlap NOTIFY overlapChanged FINAL REVISION 3)
     Q_PROPERTY(QQmlComponent *delegate READ delegate WRITE setDelegate NOTIFY delegateChanged FINAL REVISION 3)
     Q_PROPERTY(int currentIndex READ currentIndex WRITE setCurrentIndex NOTIFY currentIndexChanged FINAL REVISION 3)
@@ -103,6 +103,7 @@ public:
 
     bool cascade() const;
     void setCascade(bool cascade);
+    void resetCascade();
 
     qreal overlap() const;
     void setOverlap(qreal overlap);
@@ -124,7 +125,7 @@ protected:
 
 Q_SIGNALS:
     void titleChanged(const QString &title);
-    Q_REVISION(3) void cascadeChanged();
+    Q_REVISION(3) void cascadeChanged(bool cascade);
     Q_REVISION(3) void overlapChanged();
     Q_REVISION(3) void delegateChanged();
     Q_REVISION(3) void currentIndexChanged();
diff --git a/src/quicktemplates2/qquickmenu_p_p.h b/src/quicktemplates2/qquickmenu_p_p.h
index 283c3708..b52f0f3f 100644
--- a/src/quicktemplates2/qquickmenu_p_p.h
+++ b/src/quicktemplates2/qquickmenu_p_p.h
@@ -102,6 +102,7 @@ public:
     void onItemActiveFocusChanged();
 
     void openSubMenu(QQuickMenuItem *item, bool activate);
+    void setParentMenu(QQuickMenu *parent);
 
     void startHoverTimer();
     void stopHoverTimer();