Initial UI in src

src/UI/UI_x_boxes.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "UI_item.hpp"
+
+class UI_x_boxes : public UI_item
+{
+    public:
+        UI_x_boxes(std::string type);
+        UI_x_boxes(std::string id, std::string type, std::string text, Color fg_color, Color bg_color, std::vector<std::string> options);
+
+        void from_json(const json& j) override;
+        json to_json() const override;
+    protected:
+        std::vector<std::string> p_options;
+        // std::vector<size_t> p_selected_multi;
+        // size_t p_selected;
+
+        // void (*p_on_change) (std::string id, int selected);
+};