public class ActivityLifecycleUtils implements Application.ActivityLifecycleCallbacks {

    public static Activity currentActivity;

    @Override
    public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
        currentActivity = activity;
    }

    @Override
    public void onActivityStarted(Activity activity) {

    }

    @Override
    public void onActivityResumed(Activity activity) {
        currentActivity = activity;
    }

    @Override
    public void onActivityPaused(Activity activity) {
        currentActivity = null;
    }

    @Override
    public void onActivityStopped(Activity activity) {

    }

    @Override
    public void onActivitySaveInstanceState(Activity activity, Bundle outState) {

    }

    @Override
    public void onActivityDestroyed(Activity activity) {

    }
}