数据库变化监听方法

1.  Cursor

void	registerContentObserver( ContentObserver observer) Register an observer that is called when changes happen to the content backing this cursor.
void	registerDataSetObserver( DataSetObserver observer) Register an observer that is called when changes happen to the contents of the this cursors data set, for example, when the data set is changed via  requery(),  deactivate(), or  close().

void	setNotificationUri( ContentResolver cr,  Uri notifyUri) Specifies a content URI to watch for changes.

2. ContentResolver

final void

registerContentObserver( Uri uri, boolean notifyForDescendents,  ContentObserver observer) Register an observer class that gets callbacks when data identified by a given content URI changes.

3. Adapter && ListAdapter

abstract void

registerDataSetObserver( DataSetObserver observer) Register an observer that is called when changes happen to the data used by this adapter.

   BaseAdapter  &&  SimpleCursorAdapter

void	notifyDataSetChanged() Notifies the attached observers that the underlying data has been changed and any View reflecting the data set should refresh itself.
void	notifyDataSetInvalidated() Notifies the attached observers that the underlying data is no longer valid or available.
void	registerDataSetObserver( DataSetObserver observer) Register an observer that is called when changes happen to the data used by this adapter.
void	unregisterDataSetObserver( DataSetObserver observer) Unregister an observer that has previously been registered with this adapter via  registerDataSetObserver(DataSetObserver).