[core] Add missing file

src/lib/score/graphics/DefaultControlImpl.hpp

@@ -0,0 +1,40 @@
+#pragma once
+#include <QGraphicsItem>
+#include <QGraphicsScene>
+#include <QPointer>
+#include <QTimer>
+
+namespace score
+{
+struct DefaultControlImpl
+{
+  static void editWidgetInContextMenu(
+      auto& self, QGraphicsScene* scene, QGraphicsItem* obj, double v)
+  {
+    self.m_value = self.unmap(v);
+
+    QPointer p{&self};
+    if constexpr(requires { self.m_noValueChangeOnMove; })
+    {
+      if(!self.m_noValueChangeOnMove)
+        self.sliderMoved();
+    }
+    else
+    {
+      self.sliderMoved();
+    }
+
+    if(p)
+    {
+      self.update();
+    }
+    else
+    {
+      QTimer::singleShot(0, &self, [scene, obj] {
+        scene->removeItem(obj);
+        delete obj;
+      });
+    }
+  }
+};
+}