update backgroud to default

returns file path to store background bitmap image (caching) @param context @param notificationId @return the file path of background image

Starts {@link #loadRows()} method after delay. It also cancels previously registered task if it has not yet executed. @param query the word to be sear

prepare bitmap from URL string @param url @return

Updates UI after loading Row done.

if UpdateBackgroundTask is already running, cancel this task and start new task.

should be called Activity's onDestroy

ArrayList of movies within specified "category". If argument is null, then returns all movie list. @param category @return

Searches query specified by mQuery, and sets the result to mRowsAdapter.

only load rows which can be prepared (executed in main thread) instantaneously. UI update is done in {@link #setRows}