1 files changed, 14 insertions, 6 deletions
diff --git a/include/cru/ui/render/RenderObject.hpp b/include/cru/ui/render/RenderObject.hpp
index f052221e..4e5c9060 100644
--- a/include/cru/ui/render/RenderObject.hpp
+++ b/include/cru/ui/render/RenderObject.hpp
@@ -3,12 +3,13 @@
 
 #include "MeasureRequirement.hpp"
 #include "cru/common/Event.hpp"
+#include "cru/ui/Base.hpp"
 
+#include <cstddef>
 #include <string>
 #include <string_view>
 
 namespace cru::ui::render {
-
 // Render object will not destroy its children when destroyed. Control must
 // manage lifecycle of its render objects. Since control will destroy its
 // children when destroyed, render objects will be destroyed along with it.
@@ -38,7 +39,7 @@ namespace cru::ui::render {
 //  Size OnMeasureContent(const MeasureRequirement& requirement) override;
 //  void OnLayoutContent(const Rect& content_rect) override;
 class RenderObject : public Object {
-  friend WindowRenderObject;
+  friend WindowHost;
 
   CRU_DEFINE_CLASS_LOG_TAG(u"cru::ui::render::RenderObject")
 
@@ -64,7 +65,7 @@ class RenderObject : public Object {
   Control* GetAttachedControl() const { return control_; }
   void SetAttachedControl(Control* new_control) { control_ = new_control; }
 
-  WindowHost* GetWindowHost() const { return ui_host_; }
+  WindowHost* GetWindowHost() const { return window_host_; }
 
   RenderObject* GetParent() const { return parent_; }
 
@@ -132,6 +133,11 @@ class RenderObject : public Object {
   // Add offset before pass point to children.
   virtual RenderObject* HitTest(const Point& point) = 0;
 
+  IEvent<WindowHost*>* AttachToHostEvent() { return &attach_to_host_event_; }
+  IEvent<std::nullptr_t>* DetachFromHostEvent() {
+    return &detach_from_host_event_;
+  }
+
  public:
   void InvalidateLayout();
   void InvalidatePaint();
@@ -190,7 +196,6 @@ class RenderObject : public Object {
   virtual void OnLayoutContent(const Rect& content_rect) = 0;
 
   virtual void OnAfterLayout();
-  static void NotifyAfterLayoutRecursive(RenderObject* render_object);
 
   virtual Rect GetPaddingRect() const;
   virtual Rect GetContentRect() const;
@@ -198,11 +203,11 @@ class RenderObject : public Object {
  private:
   void SetParent(RenderObject* new_parent);
 
-  void SetRenderHostRecursive(WindowHost* host);
+  void SetWindowHostRecursive(WindowHost* host);
 
  private:
   Control* control_ = nullptr;
-  WindowHost* ui_host_ = nullptr;
+  WindowHost* window_host_ = nullptr;
 
   RenderObject* parent_ = nullptr;
   std::vector<RenderObject*> children_{};
@@ -217,5 +222,8 @@ class RenderObject : public Object {
 
   Thickness margin_{};
   Thickness padding_{};
+
+  Event<WindowHost*> attach_to_host_event_;
+  Event<std::nullptr_t> detach_from_host_event_;
 };
 }  // namespace cru::ui::render