generated ui nodes indexing

src/graphics/ui/elements/UINode.cpp

@@ -1,5 +1,6 @@
 #include "UINode.h"
 
+#include "containers.h"
 #include "../../core/Batch2D.h"
 
 using gui::UINode;
@@ -256,3 +257,19 @@ void UINode::setGravity(Gravity gravity) {
         reposition();
     }
 }
+
+void UINode::getIndices(
+    std::shared_ptr<UINode> node,
+    std::unordered_map<std::string, std::shared_ptr<UINode>>& map
+) {
+    const std::string& id = node->getId();
+    if (!id.empty()) {
+        map[id] = node;
+    }
+    auto container = std::dynamic_pointer_cast<gui::Container>(node);
+    if (container) {
+        for (auto subnode : container->getNodes()) {
+            getIndices(subnode, map);
+        }
+    }
+}