안드로이드 에러/RuntimeException: 4개의 글
RecyclerView ScrollBar(Attempt to invoke virtual method 'boolean android.support.v7.widget.RecyclerView$LayoutManager.canScrollVertically()' on a null object reference)
MediaRecorder(java.lang.RuntimeException: stop failed.)
Custom View 호출 에러(Unable to start activity ComponentInfo~)
Fragment 재실행 에러(make sure class name exists, ~~)