Added a base class MarkerList::MarkerListHolder, and used it to remove the getMarkers() method from Component.

modules/juce_gui_basics/components/juce_Component.cpp

@@ -2139,12 +2139,6 @@ void Component::copyAllExplicitColoursTo (Component& target) const
         target.colourChanged();
 }
 
-//==============================================================================
-MarkerList* Component::getMarkers (bool /*xAxis*/)
-{
-    return nullptr;
-}
-
 //==============================================================================
 Component::Positioner::Positioner (Component& c) noexcept
     : component (c)

modules/juce_gui_basics/components/juce_Component.h

@@ -2105,14 +2105,6 @@ public:
     */
     virtual void colourChanged();
 
-    //==============================================================================
-    /** Components can implement this method to provide a MarkerList.
-        The default implementation of this method returns nullptr, but you can override
-        it to return a pointer to the component's marker list. If xAxis is true, it should
-        return the X marker list; if false, it should return the Y markers.
-    */
-    virtual MarkerList* getMarkers (bool xAxis);
-
     //==============================================================================
     /** Returns the underlying native window handle for this component.
 

modules/juce_gui_basics/drawables/juce_Drawable.h

@@ -33,7 +33,8 @@ namespace juce
 
     @see DrawableComposite, DrawableImage, DrawablePath, DrawableText
 */
-class JUCE_API  Drawable  : public Component
+class JUCE_API  Drawable  : public Component,
+                            public MarkerList::MarkerListHolder
 {
 protected:
     //==============================================================================
@@ -225,6 +226,8 @@ public:
     */
     static void registerDrawableTypeHandlers (ComponentBuilder& componentBuilder);
 
+    MarkerList* getMarkers (bool) override          { return nullptr; }
+
 protected:
     //==============================================================================
     friend class DrawableComposite;

modules/juce_gui_basics/positioning/juce_MarkerList.h

@@ -146,6 +146,16 @@ public:
     /** Synchronously calls markersChanged() on all the registered listeners. */
     void markersHaveChanged();
 
+    //==============================================================================
+    /** A base class for objects that want to provide a MarkerList. */
+    struct MarkerListHolder
+    {
+        virtual ~MarkerListHolder() {}
+
+        /** Objects can implement this method to provide a MarkerList. */
+        virtual MarkerList* getMarkers (bool xAxis) = 0;
+    };
+
     //==============================================================================
     /** Forms a wrapper around a ValueTree that can be used for storing a MarkerList. */
     class ValueTreeWrapper

modules/juce_gui_basics/positioning/juce_RelativeCoordinatePositioner.cpp

@@ -73,19 +73,28 @@ struct MarkerListScope  : public Expression::Scope
     static const MarkerList::Marker* findMarker (Component& component, const String& name, MarkerList*& list)
     {
         const MarkerList::Marker* marker = nullptr;
-        list = component.getMarkers (true);
 
-        if (list != nullptr)
-            marker = list->getMarker (name);
+        auto* mlh = dynamic_cast<MarkerList::MarkerListHolder*> (&component);
 
-        if (marker == nullptr)
+        if (mlh != nullptr)
         {
-            list = component.getMarkers (false);
+            list = mlh->getMarkers (true);
 
             if (list != nullptr)
                 marker = list->getMarker (name);
         }
 
+        if (marker == nullptr)
+        {
+            if (mlh != nullptr)
+            {
+                list = mlh->getMarkers (false);
+
+                if (list != nullptr)
+                    marker = list->getMarker (name);
+            }
+        }
+
         return marker;
     }
 
@@ -117,7 +126,7 @@ Expression RelativeCoordinatePositionerBase::ComponentScope::getSymbolValue (con
     {
         MarkerList* list;
 
-        if (const MarkerList::Marker* const marker = MarkerListScope::findMarker (*parent, symbol, list))
+        if (auto* marker = MarkerListScope::findMarker (*parent, symbol, list))
         {
             MarkerListScope scope (*parent);
             return Expression (marker->position.getExpression().evaluate (scope));
@@ -175,7 +184,7 @@ public:
                 break;
 
             default:
-                if (Component* const parent = component.getParentComponent())
+                if (auto* parent = component.getParentComponent())
                 {
                     MarkerList* list;
 
@@ -186,8 +195,12 @@ public:
                     else
                     {
                         // The marker we want doesn't exist, so watch all lists in case they change and the marker appears later..
-                        positioner.registerMarkerListListener (parent->getMarkers (true));
-                        positioner.registerMarkerListListener (parent->getMarkers (false));
+                        if (auto* mlh = dynamic_cast<MarkerList::MarkerListHolder*> (parent))
+                        {
+                            positioner.registerMarkerListListener (mlh->getMarkers (true));
+                            positioner.registerMarkerListListener (mlh->getMarkers (false));
+                        }
+
                         ok = false;
                     }
                 }