PhoneGapFileSystem example: Read/Write txt/mp3 to/from public folder


newest edit Please see the last post for complete example code!

Hi. I have deployed the phonegap example PhoneGapFileSystem with phonegap but it gives me an error at startup:

Uncaught ReferenceError: LocalFileSystem is not defined.
line 15 column 32

I have not changed the example. Can anyone confirm and/or correct this error? I don’t understand what’s wrong

SDcard SQL saving

The change was at PhoneGap’s end. For some reason, PhoneGap Build’s default version of the File library isn’t in PhoneGap Build. It’s a bug in PhoneGap.

The workaround is easy. In Project Properties, open PhoneGap configxml. Change the line for cordova-file-plugin so that it has the version number for the library:

<gap:plugin name="cordova-plugin-file" source="npm" version="3.0.0"/>

Version 3 of the library is there and it works fine.


first of all I have to thank you for your prompt and compentent help.

Yes, now the example works. But I can’t locate the textfile on my android.

This is the code:
Dim folder = "storage"
Dim filename = folder & “/” & “textfile.txt”

But even with TotalCommander I can’t find the file on the device.

When I try to set another folder:
Dim folder = “storage/emulated/0/abcfolder”

(/storage/emulated/0/is my main directory whereas /storage/sdcard1 is the main directory of the sd card)

…then the app starts with an error message:
Error writing: 9

I am confused because I didn’t expect running into such an error…


This isn’t really an AppStudio issue - you’ll need to look at the PhoneGap docs:


It took me two days and night (I hate the poor ability to debug PhoneGap builds…) to finish my task:

read/write text files and read mp3 files to/from public main (root) directory of my android device.

But I made it… finaly… here is the code:

You need 4 Buttons: btWrite, btReadTxt, btReadMp3, btPath as well as
audio1 control and TextArea1.

Permission for Cordova File Plugin needs to be set in config.xml:
< gap:plugin name=“cordova-plugin-file” source=“npm” version=“3.0.0”/>

Dim folder
Dim fileName
Dim dataToWrite = "This is the data to write." 'what needs to be written in txt file

'Where to Store Files (Android):
'cordova.file.dataDirectory - Persistent and private data storage within the application's sandbox
'cordova.file.cacheDirectory -  The OS may delete these files when the device runs low on storage
'cordova.file.externalApplicationStorageDirectory - Application Space On external storage
'cordova.file.externalDataDirectory - App-specific data files On external storage
'cordova.file.externalCacheDirectory - Application cache On external storage
'cordova.file.externalRootDirectory - External storage (SD card) root

Function btPath_onclick()
End Function

'############ READ txt / mp3 file

Function btReadTxt_onclick()
  folder = "storage"
  fileName = folder & "/" & "text.txt"  
  Call ReadFilePart1of2()
End Function

Function btReadMp3_onclick()
  folder = "storage"
  fileName = folder & "/" & "ding.mp3"  
  Call ReadFilePart1of2()
End Function

Sub ReadFilePart1of2()
 'needs public var: folder, fileName
    'window.resolveLocalFileSystemURL(cordova.file.externalDataDirectory, gotFileSystemR, failPermissionR) 
    window.resolveLocalFileSystemURL(cordova.file.externalRootDirectory, gotFileSystemR, failPermissionR) 
  End Sub
    Function failPermissionR(error)
      Call AddLog("no permission for folder")
    End Function   
    Sub gotFileSystemR(fs)
      dataDir = fs.getDirectory(folder, {create: True}) 
      fs.getFile(fileName, {create: False }, gotFileEntryR, failExistR) 
    End Sub
        'if doesn't exist
        Sub failExistR(error)
          Call AddLog("This file does not exist!")
        End Sub
        'if exist...
        Sub gotFileEntryR(fe)
          fe.file(gotFileReader, failGetFileReader)
        End Function
          Function failGetFileReader(error)
            Call AddLog("Could not read file")
          End Function
          Function gotFileReader(fileBlob)
            reader = new FileReader()

            'if it's a mp3
            reader.onload = readSuccess
            'if it's a text file
            'reader.onloadend = GetRef(readData)      
            'Alternative from
              'var reader = new FileReader();
              'reader.onloadend = Function(e) {
              '        console.log("Text is: "+this.result);
              '        document.querySelector("#textArea").innerHTML = this.result;
          End Function
            Function readSuccess(e)
              AddLog("file content: " & this.result)
              'if it's a mp3
              Audio1.src = this.result
End Function  

'######## WRITE txt file

Function btWrite_onclick()
  folder = "storage"
  fileName = folder & "/" & "text.txt"
  Call WriteFilePart1of2()
  'to be continued at WriteFilePart2of2...
End Sub

Function WriteFilePart1of2()
 'needs public var: folder, fileName, dataToWrite

    'window.resolveLocalFileSystemURL(cordova.file.externalDataDirectory, gotFileSystemW, failPermissionW) 
    window.resolveLocalFileSystemURL(cordova.file.externalRootDirectory, gotFileSystemW, failPermissionW) 
  End Function
    Function failPermissionW(error)
      Call AddLog("no permission for folder")
      Call WriteFilePart2of2()
    End Function  
    Function gotFileSystemW(fs)
      dataDir = fs.getDirectory(folder, {create: True}) 
      fs.getFile(fileName, {create: True }, gotFileEntryW, failExistW)
    End Function
      Function failExistW(error)
        Call AddLog("file does not yet exist")
      End Function
      Function gotFileEntryW(fe)
        fe.createWriter(gotFileWriter, failGetFileWriter)
      End Function
          Function failGetFileWriter(error)
            'AddLog("Error writing: " + error.code)
            Call WriteFilePart2of2()
          End Function
          Function gotFileWriter(fw) 
            'fileWriter = fw
            fw.onwrite = GetRef(writeSuccess)
            'Alternative from
              'var blob = new Blob([Log], {type:'text/plain'});
          End Function
              Function writeSuccess(evt)
                  Call WriteFilePart2of2(True)
              End Function
  Sub WriteFilePart2of2(wasOkay)
    If wasOkay = True Then
      Call AddLog("write: ok")
      Call AddLog("could not write")
    End If
End Sub

'######### log

Sub AddLog(txt)
  TextArea1.text = txt & vbCRLF & TextArea1.text
End Sub


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