[UI] Loop thread to main thread WindowedAppContext

src/xenia/ui/windowed_app_context_android.h

@@ -0,0 +1,61 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2021 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_UI_WINDOWED_APP_CONTEXT_ANDROID_H_
+#define XENIA_UI_WINDOWED_APP_CONTEXT_ANDROID_H_
+
+#include <android/native_activity.h>
+#include <memory>
+
+#include "xenia/ui/windowed_app_context.h"
+
+namespace xe {
+namespace ui {
+
+class WindowedApp;
+
+class AndroidWindowedAppContext final : public WindowedAppContext {
+ public:
+  // For calling from android.app.func_name exports.
+  static void StartAppOnNativeActivityCreate(
+      ANativeActivity* activity, void* saved_state, size_t saved_state_size,
+      std::unique_ptr<WindowedApp> (*app_creator)(
+          WindowedAppContext& app_context));
+
+  // Defined in the translation unit where WindowedApp is complete because of
+  // std::unique_ptr.
+  ~AndroidWindowedAppContext();
+
+  ANativeActivity* activity() const { return activity_; }
+  WindowedApp* app() const { return app_.get(); }
+
+  void NotifyUILoopOfPendingFunctions() override;
+
+  void PlatformQuitFromUIThread() override;
+
+ private:
+  explicit AndroidWindowedAppContext(ANativeActivity* activity);
+  bool InitializeApp(std::unique_ptr<WindowedApp> (*app_creator)(
+      WindowedAppContext& app_context));
+
+  // TODO(Triang3l): Switch from ANativeActivity to the context itself being the
+  // object for communication with the Java code when NativeActivity isn't used
+  // anymore as its functionality is heavily limited.
+  ANativeActivity* activity_;
+  std::unique_ptr<WindowedApp> app_;
+
+  // TODO(Triang3l): The rest of the context, including quit handler (and the
+  // destructor) calling `finish` on the activity, UI looper notification
+  // posting, etc.
+};
+
+}  // namespace ui
+}  // namespace xe
+
+#endif  // XENIA_UI_WINDOWED_APP_CONTEXT_ANDROID_H_