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androidpreferences

Can SharedPreferences be shared among different Android applications?


As I checked in APIs description for getSharedPreferences(String, int),Second attribute is defining accessibility mode and can take 0 or MODE_PRIVATE for the default operation, MODE_WORLD_READABLE and MODE_WORLD_WRITEABLE to control permissions.

But there is this small note in API description:

Note: currently this class (android.content.SharedPreferences) does not support use across multiple processes. This will be added later.

Moreover in Mark L. Murphy book "beginning Android 2" he mentioned:

(Eventually, preferences might be shareable across applications, but that is not supported as of the time of this writing)

Im so confused! does this mean that MODE_WORLD_READABLE and MODE_WORLD_WRITEABLE of getSharedPrefrences is there but NOT SUPPORTED YET in latest API level???

Thanks! Migan


Solution

  • My book reference is based upon that comment.

    Moreover, making any file MODE_WORLD_READABLE or (worse) MODE_WORLD_WRITEABLE is a bad idea. You lose any hope of security.

    If you wish to share data between two applications, there are a myriad of solutions, such as:

    • service with an API exposed by AIDL
    • service with an API exposed via commands sent via startService() and responses sent via a Messenger or createPendingResult() PendingIntent or something
    • content provider
    • broadcast Intents

    All of those allow you to define permissions for integration and let you control the granularity of access.