android broadcastreceiver中找不到新的通话记录

public class CallLogObserver extends ContentObserver {
    private static final String TAG = "CallLogObserver";
    private Context mContext;

    public CallLogObserver(Context context) {
        super(null);
        mContext = context;
    }

    @Override
    public void onChange(boolean selfChange) {
        super.onChange(selfChange);
        // 处理通话记录变化的逻辑
        Log.d(TAG, "Call log changed");
    }

    public void register() {
        // 注册ContentObserver
        mContext.getContentResolver().registerContentObserver(
                CallLog.Calls.CONTENT_URI,
                true,
                this
        );
    }

    public void unregister() {
        // 注销ContentObserver
        mContext.getContentResolver().unregisterContentObserver(this);
    }
}

CallLogObserver callLogObserver = new CallLogObserver(context);
callLogObserver.register();