attachment property Null safety

QChatSystemNotificationAttachment? attachment
@JsonKey(fromJson: QChatSystemNotificationAttachment._fromJson, toJson: QChatSystemNotificationAttachment._toJson), read / write

通知附件字符串解析后的结构

Implementation

@JsonKey(
    fromJson: QChatSystemNotificationAttachment._fromJson,
    toJson: QChatSystemNotificationAttachment._toJson)
QChatSystemNotificationAttachment? attachment;