安装新版本后如何保留RMS？
我在诺基亚 S40 上安装了 j2me 应用程序。 一些配置数据存储在 RMS 中。 是否可以用新版本覆盖已安装的应用程序？ 新版本如何保留RMS？
如果可以的话能否设置为升级时的默认操作，避免用户误删数据？
I have an j2me application installed on a Nokia S40. Some configuration data is stored in the RMS. Is it possible to overwrite the installed app with a new version? How to keep RMS in the new version?
If it is possible can it be set as a default operation when upgrading to avoid the user accidentally delete the data?
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如果您的手机在不询问用户的情况下自动删除 RMS 数据库，那么这是一个违反 MIDP 规范的巨大错误。
我假设您使用的是零售手机，而不是原型机。
始终值得检查是否可以使用诺基亚 PC 工具升级固件。
如果升级过程询问用户是否删除旧的 RMS 数据，您可能无能为力来阻止询问。
通常最好的做法是在远程服务器上同步配置数据，并在其不可用时重新下载。
If your phone automatically deletes the RMS database without asking the user, it's a huge bug that goes against the MIDP specifications.
I assume you are using a retail phone, not a prototype.
It's always worth checking if the firmware can be upgraded with nokia PC tool.
If the upgrade process asks the user whether to delete old RMS data, there is probably little you can do to prevent the question being asked.
It's usually good practice to synchronize configuration data on a remote server and re-download it when it becomes unavailable.
从浏览器安装新版本时，应用程序会保留 RMS 并从设备中删除旧版本。
从蓝牙安装时，旧版本不会被删除，新版本也不会获得旧的 RMS。
某些诺基亚 S60 设备会询问用户是否要保留 RMS。 但对于 S40 来说就是这样。
When installing a new version from the browser the application keeps the RMS and removes the old version from the device.
When installing from bluetooth the old version isn't removed and the new version doesn't get the old RMS.
Some Nokia S60 devices asks if the user wants to keep the RMS. But for S40 that is how it works.
基本上，您对安装和更新过程没有任何控制权。 电话环境很重要。 有些手机会询问用户是否保存RMS数据，但这无法由开发者或用户控制
Basically, you don't have any control over the installation and update process. The phone environment takes care. Some phones ask the user whether to save the RMS data or not, but that cannot be controlled by the developer or the user
正如所说，您无法控制安装过程，操作系统会询问用户是否要保留以前的数据或删除它。
但是，您可以在应用程序 RMS 数据中包含版本号，并且在加载应用程序时，您可以检测它是否来自以前的版本，并决定更新它或重置为新的默认值。
As was said you can't control the installation procedure, the OS asks the user if it wants to keep the previous data or erase it.
However you can include a version number in the application RMS data and when you load the application you can detect if it was from a previous version and decide to update it or reset to the new default.
特别是在诺基亚 S40 上，本机安装程序在升级过程中询问用户是否要保留应用程序数据。 如果用户决定清除数据，您的 MIDlet 的 RMS 数据（以及文件系统上的 MIDlet 的私有文件夹）将被删除。
您可能会在特定设备上找到解决此问题的方法，特别是如果您的 MIDlet 由制造商或运营商签名，但实际上没有万无一失且可移植的方法来在升级时保留数据。 您应该考虑将数据保存在服务器上。
Specifically on Nokia S40, the native installer asks the user during the upgrade whether he/she would like to keep the application data. If the user decides to clear the data, your MIDlet's RMS data (and also the MIDlet's private folder on the file system) will be deleted.
You might find ways around this on specific devices, especially if your MIDlet is signed by manufacturer or operator, but there's really no foolproof and portable way to keep data over upgrades. You should consider saving the data on a server.