[core, ios, macos] Added layers and sources properties to MGLStyle

Added new layers and sources properties to MGLStyle that contain all the style’s layers and sources, respectively. These properties are KVC-compliant with all the mutable to-many methods. Layers are ordered from topmost to bottommost, for consistency with Cocoa APIs where front/first means top and back/last means bottom.

Also added storage for mbgl::style::Source in MGLSource proper for wrapping AnnotationSource. Until the style finishes loading, its name property is set to nil.

Fixes #6003.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/mbgl/style/style.hpp b/src/mbgl/style/style.hpp
index 2875311c63..1da22b8cf3 100644
--- a/src/mbgl/style/style.hpp
+++ b/src/mbgl/style/style.hpp
@@ -64,11 +64,14 @@ public:
         return lastError;
     }
 
+    std::vector<const Source*> getSources() const;
+    std::vector<Source*> getSources();
     Source* getSource(const std::string& id) const;
     void addSource(std::unique_ptr<Source>);
     std::unique_ptr<Source> removeSource(const std::string& sourceID);
 
     std::vector<const Layer*> getLayers() const;
+    std::vector<Layer*> getLayers();
     Layer* getLayer(const std::string& id) const;
     Layer* addLayer(std::unique_ptr<Layer>,
                     optional<std::string> beforeLayerID = {});