Android rayshader sample.

samples/android_sample/jni/activity_handler.h

Index: samples/android_sample/jni/activity_handler.h
===================================================================
--- samples/android_sample/jni/activity_handler.h	(revision 0)
+++ samples/android_sample/jni/activity_handler.h	(revision 0)
@@ -0,0 +1,25 @@
+#ifndef ACTIVITY_HANDLER_H
+#define ACTIVITY_HANDLER_H
+
+class ActivityHandler {
+  public:
+    virtual int32_t OnActivate() = 0;
+    virtual void OnDeactivate() = 0;
+    virtual int32_t OnStep() = 0;
+    virtual void OnStart() {}
+    virtual void OnResume() {}
+    virtual void OnPause() {}
+    virtual void OnStop() {}
+    virtual void OnDestroy() {}
+    virtual void OnSaveState(void** data, size_t* size) {}
+    virtual void OnConfigurationChanged() {}
+    virtual void OnLowMemory() {}
+    virtual void OnCreateWindow() {}
+    virtual void OnDestroyWindow() {}
+    virtual void OnGainedFocus() {}
+    virtual void OnLostFocus() {}
+    virtual ~ActivityHandler() {}
+};
+
+#endif
+