Android Question Flash drive

[David Riley]

I bought B4A to rewrite a data logger I wrote in VB6. It requires the data to be written to a removable flash drive.
The kitkat dictate of only accessing files in Android/data/b4a.example/ does not seem to present a problem.
However I don't see how to address the secondary external storage and create the file and directories. Please would someone write me a few lines of example code that will work on Nexus 7 to get me started.
Thanks.

 

[EddyW]

Look at command File.DirRootExternal
With this command you goto the flash drive

 

[NJDude]

Look at command File.DirRootExternal
With this command you goto the flash drive

That's not correct, DirRootExternal points to the INTERNAL SDCard.

 

[Erel]

There is no API to get the path of the secondary storage. See this thread for a possible solution: http://www.b4x.com/android/forum/threads/external-sd-card-root-folder.22532/

 

[EddyW]

Ok thought he mean the internal SD Card because most tablets cant use a external USB drive (so far i know)

 

[DonManfred]

Ok thought he mean the internal SD Card because most tablets cant use a external USB drive (so far i know)

I have an Samsung Galaxy Note 3 Tablet 10,1 and it HAS two SDCards like my Phone. An internal and an external.
I found the folder like suggested in above thread under /mnt/sdcard/exStorages/SdCard but it may vary in different devices...

 

[David Riley]

I'm going round in circles. I cannot find anything with B4A that sees the flash drive.
Using a Nexus 7 2013, otg cable and 4GB drive. OTG Disk Explorer Lite is letting me look at files and directories.
If kitkat only allows reading or writing in Android/data/MyAppName/ , how do these directories get created ?

 

[Erel]

You should be able to create the folder yourself. Note that it is not MyAppName. The folder is based on the package name.

There is a new method in Android 4.4 that allows you to get the path:

Sub Activity_Create(FirstTime As Boolean)
   Dim paths() As Object = GetContext.RunMethod("getExternalFilesDirs", Array(Null))
   For Each p As Object In paths
     Log(p)
   Next
 End Sub

Sub GetContext As JavaObject
   Return GetBA.GetField("context")
End Sub

Sub GetBA As JavaObject
  Dim jo As JavaObject
  Dim cls As String = Me
  cls = cls.SubString("class ".Length)
  jo.InitializeStatic(cls)
  Return jo.GetFieldJO("processBA")
End Sub

 

[David Riley]

The result is /storage/emulated/0/Android/data/b4a.example/files .
With or without the flash drive connected.

 

[Erel]

The API is described here: http://developer.android.com/refere...t.html#getExternalFilesDirs(java.lang.String)

 

[David Riley]

But it states "The returned paths do not include transient devices, such as USB flash drives." ?

 

[Erel]

This is correct. There is no API to find USB flash drives. You can try to run df with Shell (Phone library) and then parse the result.