Add radio button with simple/advanced view, add widget visibility

include/gui/RadioButton.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "Widget.hpp"
+
+#include <mglpp/graphics/Text.hpp>
+#include <vector>
+#include <functional>
+
+namespace gsr {
+    class RadioButton : public Widget {
+    public:
+        RadioButton(mgl::Font *font);
+        RadioButton(const RadioButton&) = delete;
+        RadioButton& operator=(const RadioButton&) = delete;
+
+        bool on_event(mgl::Event &event, mgl::Window &window, mgl::vec2f offset) override;
+        void draw(mgl::Window &window, mgl::vec2f offset) override;
+
+        void add_item(const std::string &text, const std::string &id);
+        void set_selected_item(const std::string &id);
+
+        mgl::vec2f get_size() override;
+
+        std::function<void(const std::string &text, const std::string &id)> on_selection_changed;
+    private:
+        void update_if_dirty();
+    private:
+        struct Item {
+            mgl::Text text;
+            std::string id;
+        };
+
+        mgl::Font *font;
+        std::vector<Item> items;
+        size_t selected_item = 0;
+        bool dirty = true;
+        mgl::vec2f size;
+    };
+}