Android 当数据库变动时更新UI数据 注册观察者监听

/**
	 * Register an observer for provider status changes - we will need to
	 * reflect them in the UI.
	 */
	private void registerObserver() {
		getContentResolver().registerContentObserver(
				ContactsContract.Contacts.CONTENT_URI, true, mObserver);
		getContentResolver().registerContentObserver(
				CallLog.Calls.CONTENT_URI, true, mObserver);
	}

	private void unregisterObserver() {
		getContentResolver().unregisterContentObserver(mObserver);
	}

	private ContentObserver mObserver = new ContentObserver(new Handler()) {

		@Override
		public void onChange(boolean selfChange) {
			isContactChanged = true;
		}
	};