I am using shared storage to write a pdf file. The file is created but it is of 0 bytes. Not able to understand what is the issue.

Below is my code

• ACTION_CREATE_DOCUMENT

  fun saveFile() {
  
   val exportIntent = Intent(Intent.ACTION_CREATE_DOCUMENT)
   exportIntent.addCategory(Intent.CATEGORY_OPENABLE)
   exportIntent.type = "application/pdf"
   val filename = "test.pdf"
   exportIntent.putExtra(Intent.EXTRA_TITLE, filename)
   startForResult.launch(exportIntent)
  }
  

• Activity result

  private val MEGABYTE = 1024 * 1024
  
  val startForResult =
   registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result: ActivityResult ->
       if (result.resultCode == Activity.RESULT_OK) {
           val intent = result.data
           if (intent?.data != null) {
               val uri: Uri = intent.data!!
               GlobalScope.launch {
                   writeFile(uri)
               }
  
  
           }
       }
   }
  

• Write file method

   fun writeFile(uri:Uri){
   val outputStream: OutputStream? =
       requireContext().contentResolver.openOutputStream(uri)
   if (outputStream != null) {
       val url = URL(some url)
       val urlConnection: HttpURLConnection =
           url.openConnection() as HttpURLConnection
       urlConnection.setRequestMethod("GET")       
       urlConnection.setDoOutput(true)
       urlConnection.connect()
  
       val inputStream: InputStream = urlConnection.getInputStream()
  
       val buffer = ByteArray(MEGABYTE)
       var bufferLength = 0
       while (inputStream.read(buffer).also { bufferLength = it } > 0) {
           outputStream.write(buffer, 0, bufferLength)
       }
  
       outputStream.close()
   }
   }
  

CodePudding user response：

Thanks to comment from @blackapps was able to work it out Removed the following

urlConnection.setRequestMethod("GET")
urlConnection.setDoOutput(true)

Correct function becomes

fun writeFile(uri: Uri, docUrl: String) {
    val outputStream: OutputStream? =
        requireContext().contentResolver.openOutputStream(uri)
    if (outputStream != null) {
        val url =
            URL(docUrl)
        val urlConnection: HttpURLConnection =
            url.openConnection() as HttpURLConnection
        urlConnection.connect()

        val inputStream: InputStream = urlConnection.getInputStream()
        val buffer = ByteArray(1024 * 1024)
        var bufferLength = 0
        while (inputStream.read(buffer).also { bufferLength = it } > 0) {
            outputStream.write(buffer, 0, bufferLength)
        }
        outputStream.close()
    }
}

CodePudding user response：

Check inputstream is accessible or not by logging inputStream.available() Must be >0

The use this logic to write inputstream to outputstream

byte[] buffer = new byte[1024];
int len;
while ((len = inputStream.read(buffer)) != -1) {
    outputStream.write(buffer, 0, len);
}
outputStream.close()