Refactor: move change listener notification logic into helpers

A dozen loops doing more or less the same, all with the comment
"intentional copy (QTBUG-54732)", are best factored out into a helper.

Most of the loops call a different QQuickItemChangeListener member, so
provide a template that expects a pointer to a QQuickItemChangeListener
member function.
Some loops have some additional logic, so provide a second template that
just calls a functor.

No functional change, but needed for follow-up fixes to focus reason
handling in Qt Quick Controls.

Pick-to: 6.2
Change-Id: I6b11e06331da44b288315fc0732009d5f34f539a
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 27 insertions, 0 deletions

diff --git a/src/quick/items/qquickitem_p.h b/src/quick/items/qquickitem_p.h
index 51ef850d5f..576d392a26 100644
--- a/src/quick/items/qquickitem_p.h
+++ b/src/quick/items/qquickitem_p.h
@@ -331,6 +331,7 @@ public:
         ImplicitWidth = 0x100,
         ImplicitHeight = 0x200,
         Enabled = 0x400,
+        AllChanges = 0xFFFFFFFF
     };
 
     Q_DECLARE_FLAGS(ChangeTypes, ChangeType)
@@ -358,6 +359,32 @@ public:
         QQuickGeometryChange gTypes;  //NOTE: not used for ==
     };
 
+    // call QQuickItemChangeListener PMF
+    template <typename Fn, typename ...Args>
+    void notifyChangeListeners(QQuickItemPrivate::ChangeTypes changeTypes, Fn &&function, Args &&...args)
+    {
+        if (changeListeners.isEmpty())
+            return;
+
+        const auto listeners = changeListeners; // NOTE: intentional copy (QTBUG-54732)
+        for (const QQuickItemPrivate::ChangeListener &change : listeners) {
+            if (change.types & changeTypes)
+                (change.listener->*function)(args...);
+        }
+    }
+    // call functor
+    template <typename Fn>
+    void notifyChangeListeners(QQuickItemPrivate::ChangeTypes changeTypes, Fn &&function) {
+        if (changeListeners.isEmpty())
+            return;
+
+        const auto listeners = changeListeners; // NOTE: intentional copy (QTBUG-54732)
+        for (const QQuickItemPrivate::ChangeListener &change : listeners) {
+            if (change.types & changeTypes)
+                function(change);
+        }
+    }
+
     struct ExtraData {
         ExtraData();