2 files changed, 40 insertions, 1 deletions
diff --git a/include/cru/ui/controls/LayoutControl.hpp b/include/cru/ui/controls/LayoutControl.hpp
index cbdb8aa2..106dd94d 100644
--- a/include/cru/ui/controls/LayoutControl.hpp
+++ b/include/cru/ui/controls/LayoutControl.hpp
@@ -5,6 +5,8 @@ namespace cru::ui::controls {
 class LayoutControl : public Control {
  protected:
   LayoutControl() = default;
+  explicit LayoutControl(render::RenderObject* container_render_object)
+      : container_render_object_(container_render_object) {}
 
  public:
   LayoutControl(const LayoutControl& other) = delete;
@@ -15,5 +17,19 @@ class LayoutControl : public Control {
 
   using Control::AddChild;
   using Control::RemoveChild;
+
+ protected:
+  // If container render object is not null. Render object of added or removed
+  // child control will automatically sync to the container render object.
+  render::RenderObject* GetContainerRenderObject() const;
+  void SetContainerRenderObject(render::RenderObject* ro) {
+    container_render_object_ = ro;
+  }
+
+  void OnAddChild(Control* child, Index position) override;
+  void OnRemoveChild(Control* child, Index position) override;
+
+ private:
+  render::RenderObject* container_render_object_ = nullptr;
 };
-}  // namespace cru::ui
+}  // namespace cru::ui::controls
diff --git a/include/cru/ui/controls/Popup.hpp b/include/cru/ui/controls/Popup.hpp
new file mode 100644
index 00000000..f17cd1b2
--- /dev/null
+++ b/include/cru/ui/controls/Popup.hpp
@@ -0,0 +1,23 @@
+#pragma once
+#include "LayoutControl.hpp"
+
+#include <memory>
+
+namespace cru::ui::controls {
+class Popup : public LayoutControl {
+ public:
+  explicit Popup(Control* attached_control = nullptr);
+
+  CRU_DELETE_COPY(Popup)
+  CRU_DELETE_MOVE(Popup)
+
+  ~Popup() override;
+
+ private:
+  std::unique_ptr<host::WindowHost> window_host_;
+
+  std::unique_ptr<render::StackLayoutRenderObject> render_object_;
+
+  Control* attached_control_;
+};
+}  // namespace cru::ui::controls