/* 아래와 같이 BackStack에 쌓여있는 EntryCount 를 얻어서 처리하면 됩니다 */
FragmentManager flagmentManager = getSupportFragmentManager();
int fragmentStackCount = flagmentManager.getBackStackEntryCount();
if(fragmentStackCount > 0){
fragmentManager.popBackStack();
return;
}else{
doubleBackCloseHandler.onBackPressed(); //더블클릭 종료 핸들러
}