Notification 구성 ① Small Icon : This is requried and set with setSmallIcon(). ② App Name : This is provided by the system. ③ Time stamp : This is provided by the system but you can override with setWhen() or hide it with setShowWhen(false). ④ Large Icon : This is optional (usually used only for contact photos; do not use it for your app icon) and set with setLargeIcon(). ⑤ Title : This is optiona..
