Android Question Give File Write permission on SDcard (in a new directory)

[Jim-WI]

I'd like to add file write permission for a file (and directory) on my SDcard. I'm on a phone with Android 10, B4A version 10.0.
It works for files in: "/storage/9016-4EF8/Android/data/b4a.example/files"
I got that directory using: GetAllSafeDirsExternal("")
I would like to be able to write file in another directory (that I created) on the SDcard.
Thanks,
Jim

 

[Erel]

B4A version 10.0.

Big mistake. Always use the latest version.

You need to use ExternalStorage: https://www.b4x.com/android/forum/t...access-sd-cards-and-usb-sticks.90238/#content

 

[DonManfred]

android.jar / targetSdkVersion / minSdkVersion

There are several versioned components that affect the compilation process and the runtime behavior of our apps. The purpose of this tutorial is to explain the differences between them and help you choose which version to use. Each Android version is mapped to an api level. You can see this...

www.b4x.com

To access SDCards you need to use the ExternalStorage Class.

ExternalStorage - Access SD cards and USB sticks

Before we start: External storage means a real sd card or a connected mass storage USB device. This class can also be used to access the secondary storage (File.DirRootExternal). This becomes relevant with newer versions of Android that restrict direct access. It has nothing to do with runtime...

www.b4x.com

 

[Jim-WI]

Thank you. I'll study ExternalStorage issues.
Jim

 

[Jim-WI]

I'm still struggling with being able to write to a file on my sdcard that is not in the directory: "/storage/9016-4EF8/Android/data/b4a.example/files"
I got that directory using: GetAllSafeDirsExternal(""). I have updated to 10.2 B4A.
I did run the FilePicker app suggest to me. That app is here: https://www.b4x.com/android/forum/t...access-sd-cards-and-usb-sticks.90238/#content
The FilePicker app can access the sdcard files (by listing them), but the details of the code to access the files seems hidden in the ExternalStorage library. I can't figure out how to get the actual file name of the sdcard file so I can that file via:
TextReader1.Initialize(File.OpenInput(File.DirRootExternal, fname)) or
fileIn = File.OpenInput(dir, fnamein) {for binary files}.
Also I'd like to access an sdcard file without having to go thru FilePicker, hopefully using its filename.
If the files are in the main stotage area (not the sdcard - /storage/emulated/0/...) I can acces them (read / write). I can also read/write files in the special sdcard directory "/storage/9016-4EF8/Android/data/b4a.example/files". BUT, I can only access sdcard files that are in that special directory.
Still looking for advice / suggestions . . . Thanks

 

[agraham]

I can that file via:
TextReader1.Initialize(File.OpenInput(File.DirRootExternal, fname))

You can't, apart from GetAllSafeDirsExternal you can only access files on the SD Card via the External Storage class methods.

 

[Jim-WI]

Thanks, agraham. I was beginning to believe that was the case.
Using GetAllSafeDirsExternal, I get one folder that is on the sdcard. It is: "/storage/9016-4EF8/Android/data/b4a.example/files". Is there a way that I can add another folder on the sdcard so it is returned when I invoke GetAllSafeDirsExternal? I'd like that folder to have the same "rights and privilages" as the b4a.example/files folder.

 

[agraham]

you can only access files on the SD Card via the External Storage class methods.