Android Question Silly question - how to save an image file to internal SD card with Fileprovider ?

[Phayao]

I hesitated long time to post this question - but honestly I'm unable to figure it out.
I can create a bitmap file with the intent camera and show it in an imageview.
But to save it with fileprovider to a file in the internal SD Card (SDK version 26) i could not do.
The fileprovider examples show how to copy from dir.assets to the shared folder and share it - but not the other way around. I tried with File.copy(imagefolder,tempfile,file.dirrootexternal,"mypic.jpg") only to get java error "file not found 'mypic.jpg' access denied".
(of course I included fileprovider.bas and modified manifest according to the fileprovider example).
I guess the solution is super-easy, please forgive my ignorance

Thanks a lot,
Chris

 

[agraham]

FileProvider is not concerned with file copying but only with file sharing.

This is how I copy a file from the SD Card to a file in the Download folder using a Stream opened by Erel's ExternalStorage class.

It is confusing, at least to me, that External Storage seems to mean either 'internal external storage' which needs PERMISSION_WRITE_EXTERNAL_STORAGE or an SD Card or USB stick which need to use the Storage Access Framework as implemented in the ExternalStorage class module. In fact I find the whole Android permission system totally baffling as Google seems to keep changing it. But then I loathe Google and Android anyway!

' in Activity_Create
    Dim rp As RuntimePermissions   
   rp.CheckAndRequest(rp.PERMISSION_WRITE_EXTERNAL_STORAGE) ' Implicit read capability if granted
   Wait For Activity_PermissionResult (Permission As String, Result As Boolean)
   Log($"PERMISSION_WRITE_EXTERNAL_STORAGE = ${Result}"$)

' then later
' Starter.MapTempDestination, = "/Download/OS Search Map.jpg"
           Dim out As OutputStream = File.OpenOutput(File.DirRootExternal, Starter.MapTempDestination, False)
           File.Copy2(Storage.OpenInputStream(extfile), out)
           out.Close

 

[Phayao]

Thanks a lot, that helps but does not solve the problem 100%.
I am using the ExternalStorage class, though the critical command now is:

File.Copy2(Storage.OpenInputStream(extFile), out)

I do not get where the extFile should come from - it is a kind of stream object i guess, but what I have is a bitmap which I want to save as file on the internal SD card. How to bring the bitmap into this extFile ? Or did i get it totally wrong ?
Thanks in advance again.

 

[agraham]

You said you could create the file and wanted to copy it to the SD Card so I showed you how to get permission and use two Streams to copy it. Now I don't understand what you mean. If you know how to create the file in External storage then using Storage.OpenInputStream should be obvious. extFile is the name of the file to copy.

 

[Phayao]

Thanks to your hints I was able to figure it out, it's actually very easy - I got confused about the Fileprovider class.
It is as you said not necessary here.
The solution is:

Sub Activity_Create(FirstTime As Boolean)
   Activity.LoadLayout("1")
   Dim rp As RuntimePermissions
   rp.CheckAndRequest(rp.PERMISSION_WRITE_EXTERNAL_STORAGE) ' Implicit read capability if granted
   Wait For Activity_PermissionResult (Permission As String, Result As Boolean)
   Log($"PERMISSION_WRITE_EXTERNAL_STORAGE = ${Result}"$)
   imageFolder = rp.GetSafeDirDefaultExternal("shared") 'shared folder as set in the manifest editor
   Log("imagefolder: "&imageFolder)
   If lastPicture.IsInitialized Then ImageView1.Bitmap = lastPicture
End Sub

Sub Button1_Click
   TakePicture
End Sub

Sub TakePicture
   Dim i As Intent
   i.Initialize("android.media.action.IMAGE_CAPTURE", "")
   File.Delete(imageFolder, tempImageFile)
   File.Delete(myFolder,"camintentTest.jpg")
   Dim p As Phone
   Dim u As Object
   Log("SDK Version: "&p.SdkVersion)
   If p.SdkVersion < 24 Then
       Dim uri As Uri
       uri.Parse("file://" & File.Combine(imageFolder, tempImageFile))
       u = uri
   Else
       u = CreateFileProviderUri(imageFolder, tempImageFile)
   End If
   i.PutExtra("output", u) 'the image will be saved to this path
   Try
       StartActivityForResult(i)
   Catch
       Msgbox("Camera is not available."&CRLF&LastException, "Camera ERROR")
   End Try
End Sub

'result arrives here
Sub ion_Event (MethodName As String, Args() As Object) As Object
   If Args(0) = -1 Then
       Try
           Dim in As Intent = Args(1)
           If File.Exists(imageFolder, tempImageFile) Then
               lastPicture = LoadBitmapSample(imageFolder, tempImageFile, ImageView1.Width, ImageView1.Height)
               ImageView1.Bitmap = lastPicture
           Else If in.HasExtra("data") Then 'try to get thumbnail instead
               Dim jo As JavaObject = in
               lastPicture = jo.RunMethodJO("getExtras", Null).RunMethod("get", Array("data"))
           End If
       Catch
           Msgbox( LastException,"ERROR")
       End Try

       ' copy to directory
       Try
           File.Copy(imageFolder,tempImageFile,myFolder,"camintentTest.jpg") ' <==== THIS IS THE WHOLE "TRICK" !!
           ' NO FILEPROVIDER OR EXTFILE NECESSARY !

           If File.Exists(myFolder,"camintentTest.jpg") Then _
               Msgbox("Image written to: camintentTest.jpg ","IMAGE SAVE")
       Catch
           Msgbox( LastException,"ERROR in copy file")
       End Try
   End If
   If lastPicture.IsInitialized Then ImageView1.Bitmap = lastPicture

   Return Null
End Sub

Sub CreateFileProviderUri (Dir As String, FileName As String) As Object
   Dim fp As JavaObject
   Dim context As JavaObject
   context.InitializeContext
   fp.InitializeStatic("android.support.v4.content.FileProvider")
   Dim f As JavaObject
   f.InitializeNewInstance("java.io.File", Array(Dir, FileName))
   Log("Packagename: "&Application.PackageName)
   Return fp.RunMethod("getUriForFile", Array(context, Application.PackageName & ".provider", f))
End Sub


Sub StartActivityForResult(i As Intent)
   Dim jo As JavaObject = GetBA
   ion = jo.CreateEvent("anywheresoftware.b4a.IOnActivityResult", "ion", Null)
   jo.RunMethod("startActivityForResult", Array As Object(ion, i))
End Sub

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

I hope that helps another beginner like me !
Thanks a lot.