Problem with July 30 2020 Version: nb184 no longer able to write and read files

[ewpatton]

Right, but if you install the app fresh on Android 11 once App Inventor targets SDK 30 (it only targets SDK 29 right now), then you won't be able to create myDir because it is not in scoped storage.

Edit: More specifically, to ease the transition App Inventor includes the requestLegacyExternalStorage flag in the manifest so that apps can still access files outside of scoped storage. Once apps target Android 11, this will be ignored (ref):

To give developers additional time for testing, apps that target Android 10 (API level 29) can still request the requestLegacyExternalStorage attribute. This flag allows apps to temporarily opt out of the changes associated with scoped storage, such as granting access to different directories and different types of media files. After you update your app to target Android 11, the system ignores the requestLegacyExternalStorage flag.

Edit 2: There is also preserveLegacyExternalStorage, which we will turn on when we target SDK 30, but this only holds if the app was installed on the device prior to upgrading to Android 11 and the grandfathering in of the permissions model goes away if you uninstall and then install fresh the app:

If you have data to migrate, it's possible to preserve the legacy storage model when a user upgrades to the new version of your app that targets Android 11. That way, the user retains access to app data that's stored in directories where your app had previously saved the data. To enable the legacy storage model for an upgrade, set the preserveLegacyExternalStorage attribute to true in your app's manifest.