4 files changed, 78 insertions, 2 deletions
diff --git a/src/osx/gui/CMakeLists.txt b/src/osx/gui/CMakeLists.txt
index 26191655..a9a75d76 100644
--- a/src/osx/gui/CMakeLists.txt
+++ b/src/osx/gui/CMakeLists.txt
@@ -2,8 +2,8 @@ set(CRU_OSX_GUI_INCLUDE_DIR ${CRU_INCLUDE_DIR}/cru/osx/gui)
 
 add_library(cru_osx_gui SHARED
 	Resource.cpp
-	UiApplication.cpp
-	Window.cpp
+	UiApplication.mm
+	Window.mm
 )
 
 target_sources(cru_osx_gui PUBLIC
diff --git a/src/osx/gui/UiApplication.mm b/src/osx/gui/UiApplication.mm
new file mode 100644
index 00000000..69f52c1f
--- /dev/null
+++ b/src/osx/gui/UiApplication.mm
@@ -0,0 +1,76 @@
+#include "cru/osx/gui/UiApplication.hpp"
+
+#include <AppKit/NSApplication.h>
+#include <algorithm>
+
+@interface AppDelegate : NSObject <NSApplicationDelegate>
+- (id)init:(cru::platform::gui::osx::details::OsxUiApplicationPrivate*)p;
+- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication*)sender;
+- (void)applicationWillTerminate:(NSNotification*)notification;
+@end
+
+namespace cru::platform::gui::osx {
+
+namespace details {
+class OsxUiApplicationPrivate {
+  friend OsxUiApplication;
+
+ public:
+  explicit OsxUiApplicationPrivate(OsxUiApplication* osx_ui_application)
+      : osx_ui_application_(osx_ui_application) {
+    app_delegate_ = [[AppDelegate alloc] init:this];
+  }
+
+  CRU_DELETE_COPY(OsxUiApplicationPrivate)
+  CRU_DELETE_MOVE(OsxUiApplicationPrivate)
+
+  ~OsxUiApplicationPrivate() = default;
+
+  void CallQuitHandlers();
+
+ private:
+  OsxUiApplication* osx_ui_application_;
+  AppDelegate* app_delegate_;
+  std::vector<std::function<void()>> quit_handlers_;
+};
+
+void OsxUiApplicationPrivate::CallQuitHandlers() {
+  for (const auto& handler : quit_handlers_) {
+    handler();
+  }
+}
+}
+
+OsxUiApplication::OsxUiApplication() : OsxGuiResource(this) {}
+
+OsxUiApplication::~OsxUiApplication() {}
+
+int OsxUiApplication::Run() {
+  [NSApp run];
+  return 0;
+}
+
+void OsxUiApplication::RequestQuit(int quit_code) {
+  [NSApp terminate:[NSNumber numberWithInteger:quit_code]];
+}
+
+void OsxUiApplication::AddOnQuitHandler(std::function<void()> handler) {
+  p_->quit_handlers_.push_back(std::move(handler));
+}
+
+}
+
+@implementation AppDelegate
+cru::platform::gui::osx::details::OsxUiApplicationPrivate* _p;
+
+- (id)init:(cru::platform::gui::osx::details::OsxUiApplicationPrivate*)p {
+  _p = p;
+  return self;
+}
+- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication*)sender {
+  return NSApplicationTerminateReply::NSTerminateNow;
+}
+- (void)applicationWillTerminate:(NSNotification*)notification {
+  _p->CallQuitHandlers();
+}
+@end
diff --git a/src/osx/gui/Window.cpp b/src/osx/gui/Window.cpp
deleted file mode 100644
index e69de29b..00000000
--- a/src/osx/gui/Window.cpp
+++ /dev/null
diff --git a/src/osx/gui/UiApplication.cpp b/src/osx/gui/Window.mm
index e69de29b..e69de29b 100644
--- a/src/osx/gui/UiApplication.cpp
+++ b/src/osx/gui/Window.mm