5 files changed, 74 insertions, 33 deletions
diff --git a/include/cru/platform/native/ui_application.hpp b/include/cru/platform/native/ui_application.hpp
index b69b1f52..edbcc578 100644
--- a/include/cru/platform/native/ui_application.hpp
+++ b/include/cru/platform/native/ui_application.hpp
@@ -3,6 +3,7 @@
 
 #include <chrono>
 #include <functional>
+#include <memory>
 #include <vector>
 
 namespace cru::platform::graph {
@@ -11,6 +12,7 @@ struct IGraphFactory;
 
 namespace cru::platform::native {
 struct INativeWindow;
+struct INativeWindowResolver;
 struct ICursorManager;
 
 // The entry point of a ui application.
@@ -39,7 +41,8 @@ struct IUiApplication : public virtual INativeResource {
   virtual void CancelTimer(unsigned long id) = 0;
 
   virtual std::vector<INativeWindow*> GetAllWindow() = 0;
-  virtual INativeWindow* CreateWindow(INativeWindow* parent) = 0;
+  virtual std::shared_ptr<INativeWindowResolver> CreateWindow(
+      INativeWindow* parent) = 0;
 
   virtual cru::platform::graph::IGraphFactory* GetGraphFactory() = 0;
 
diff --git a/include/cru/platform/native/window.hpp b/include/cru/platform/native/window.hpp
index bfaf170b..84193a13 100644
--- a/include/cru/platform/native/window.hpp
+++ b/include/cru/platform/native/window.hpp
@@ -12,22 +12,17 @@ struct IPainter;
 }
 
 namespace cru::platform::native {
+struct INativeWindowResolver;
+
 // Represents a native window, which exposes some low-level events and
 // operations.
 //
-// Although you can always retain an instance of this class, the real window
-// associated with it might be have already been destroyed by explicitly calling
-// Close or closed by the user, which leads to an invalid instance. You can
-// check the validity by IsValid. When you call perform native operations on the
-// invalid instance, there is no effect.
+// Usually you save an INativeWindowResolver after creating a window. Because
+// window may be destroyed when user do certain actions like click the close
+// button. Then the INativeWindow instance is destroyed and
+// INativeWindowResolver::Resolve return nullptr to indicate the fact.
 struct INativeWindow : virtual INativeResource {
-  // Return if the window is still valid, that is, hasn't been closed or
-  // destroyed.
-  virtual bool IsValid() = 0;
-
-  // Set if the instance is deleted automatically when the window is destroyed
-  // by other ways. Default is true.
-  virtual void SetDeleteThisOnDestroy(bool value) = 0;
+  virtual std::shared_ptr<INativeWindowResolver> GetResolver() = 0;
 
   virtual void Close() = 0;
 
@@ -71,4 +66,9 @@ struct INativeWindow : virtual INativeResource {
   virtual IEvent<int>* KeyDownEvent() = 0;
   virtual IEvent<int>* KeyUpEvent() = 0;
 };
+
+// See INativeWindow for more info.
+struct INativeWindowResolver : virtual INativeResource {
+  virtual INativeWindow* Resolve() = 0;
+};
 }  // namespace cru::platform::native
diff --git a/include/cru/ui/window.hpp b/include/cru/ui/window.hpp
index 35d6772e..105063d9 100644
--- a/include/cru/ui/window.hpp
+++ b/include/cru/ui/window.hpp
@@ -9,7 +9,8 @@
 
 namespace cru::platform::native {
 struct INativeWindow;
-}
+struct INativeWindowResolver;
+}  // namespace cru::platform::native
 
 namespace cru::ui {
 namespace render {
@@ -38,13 +39,11 @@ class Window final : public ContentControl, public SelfResolvable<Window> {
   ~Window() override;
 
  public:
-  std::string_view GetControlType() const override final;
+  std::string_view GetControlType() const final;
 
   render::RenderObject* GetRenderObject() const override;
 
-  platform::native::INativeWindow* GetNativeWindow() const {
-    return native_window_;
-  }
+  platform::native::INativeWindow* GetNativeWindow();
 
   // Get current control that mouse hovers on. This ignores the mouse-capture
   // control. Even when mouse is captured by another control, this function
@@ -85,22 +84,29 @@ class Window final : public ContentControl, public SelfResolvable<Window> {
 
   //*************** region: native messages ***************
 
-  void OnNativeDestroy(std::nullptr_t);
-  void OnNativePaint(std::nullptr_t);
-  void OnNativeResize(const Size& size);
+  void OnNativeDestroy(platform::native::INativeWindow* window, std::nullptr_t);
+  void OnNativePaint(platform::native::INativeWindow* window, std::nullptr_t);
+  void OnNativeResize(platform::native::INativeWindow* window,
+                      const Size& size);
 
-  void OnNativeFocus(cru::platform::native::FocusChangeType focus);
+  void OnNativeFocus(platform::native::INativeWindow* window,
+                     cru::platform::native::FocusChangeType focus);
 
   void OnNativeMouseEnterLeave(
+      platform::native::INativeWindow* window,
       cru::platform::native::MouseEnterLeaveType enter);
-  void OnNativeMouseMove(const Point& point);
+  void OnNativeMouseMove(platform::native::INativeWindow* window,
+                         const Point& point);
   void OnNativeMouseDown(
+      platform::native::INativeWindow* window,
       const platform::native::NativeMouseButtonEventArgs& args);
   void OnNativeMouseUp(
+      platform::native::INativeWindow* window,
       const platform::native::NativeMouseButtonEventArgs& args);
 
-  void OnNativeKeyDown(int virtual_code);
-  void OnNativeKeyUp(int virtual_code);
+  void OnNativeKeyDown(platform::native::INativeWindow* window,
+                       int virtual_code);
+  void OnNativeKeyUp(platform::native::INativeWindow* window, int virtual_code);
 
   //*************** region: event dispatcher helper ***************
 
@@ -112,7 +118,9 @@ class Window final : public ContentControl, public SelfResolvable<Window> {
   void UpdateCursor();
 
  private:
-  platform::native::INativeWindow* native_window_;
+  std::shared_ptr<platform::native::INativeWindowResolver>
+      native_window_resolver_;
+
   std::vector<EventRevokerGuard> event_revoker_guards_;
 
   std::unique_ptr<render::WindowRenderObject> render_object_;
diff --git a/include/cru/win/native/ui_application.hpp b/include/cru/win/native/ui_application.hpp
index 80e358e4..73f67abe 100644
--- a/include/cru/win/native/ui_application.hpp
+++ b/include/cru/win/native/ui_application.hpp
@@ -45,7 +45,7 @@ class WinUiApplication : public WinNativeResource,
   void CancelTimer(unsigned long id) override;
 
   std::vector<INativeWindow*> GetAllWindow() override;
-  INativeWindow* CreateWindow(INativeWindow* parent) override;
+  std::shared_ptr<INativeWindowResolver> CreateWindow(INativeWindow* parent) override;
 
   cru::platform::graph::IGraphFactory* GetGraphFactory() override;
 
diff --git a/include/cru/win/native/window.hpp b/include/cru/win/native/window.hpp
index 9752682f..3c883338 100644
--- a/include/cru/win/native/window.hpp
+++ b/include/cru/win/native/window.hpp
@@ -12,12 +12,12 @@ class WinCursor;
 class WindowClass;
 class WindowManager;
 class WindowRenderTarget;
+class WinNativeWindowResolver;
 
 class WinNativeWindow : public WinNativeResource, public virtual INativeWindow {
  public:
-  WinNativeWindow(WinUiApplication* application,
-                  WindowClass* window_class, DWORD window_style,
-                  WinNativeWindow* parent);
+  WinNativeWindow(WinUiApplication* application, WindowClass* window_class,
+                  DWORD window_style, WinNativeWindow* parent);
 
   CRU_DELETE_COPY(WinNativeWindow)
   CRU_DELETE_MOVE(WinNativeWindow)
@@ -25,8 +25,9 @@ class WinNativeWindow : public WinNativeResource, public virtual INativeWindow {
   ~WinNativeWindow() override;
 
  public:
-  bool IsValid() override;
-  void SetDeleteThisOnDestroy(bool value) override;
+  std::shared_ptr<INativeWindowResolver> GetResolver() override {
+    return std::static_pointer_cast<INativeWindowResolver>(resolver_);
+  }
 
   void Close() override;
 
@@ -118,7 +119,14 @@ class WinNativeWindow : public WinNativeResource, public virtual INativeWindow {
  private:
   WinUiApplication* application_;
 
-  bool delete_this_on_destroy_ = true;
+  // when delete is called first, it set this to true to indicate
+  // destroy message handler not to double delete this instance;
+  // when destroy handler is called first (by user action or method
+  // Close), it set this to true to indicate delete not call Close
+  // again.
+  bool sync_flag_ = false;
+
+  std::shared_ptr<WinNativeWindowResolver> resolver_;
 
   HWND hwnd_;
   WinNativeWindow* parent_window_;
@@ -143,4 +151,26 @@ class WinNativeWindow : public WinNativeResource, public virtual INativeWindow {
 
   Event<WindowNativeMessageEventArgs&> native_message_event_;
 };
+
+class WinNativeWindowResolver : public WinNativeResource,
+                                public virtual INativeWindowResolver {
+  friend WinNativeWindow::~WinNativeWindow();
+
+ public:
+  WinNativeWindowResolver(WinNativeWindow* window) : window_(window) {}
+
+  CRU_DELETE_COPY(WinNativeWindowResolver)
+  CRU_DELETE_MOVE(WinNativeWindowResolver)
+
+  ~WinNativeWindowResolver() override = default;
+
+ public:
+  INativeWindow* Resolve() override { return window_; }
+
+ private:
+  void Reset();
+
+ private:
+  WinNativeWindow* window_;
+};
 }  // namespace cru::platform::native::win