DownloadManager not working for Android 10 (Q)

Question

I've been beating my head against this issue for quite awhile... I am updating an app that uses DownloadManger to do a simple task like downloading a file to the external storage public directory ie:

Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)

Everything works fine here from Android api 19-28. Its when testing on API 29 (Q/10) is where issues occur. Android implemented scoped storage and so deprecated the getExternalStoragePublicDirectory... As a result I need to figure out a compatible solution to support APIs 19- 29 . I cannot use internal application storage since DownloadManager will throw a SecurityException. Androids documentation states that I can use the DownloadManager.Request setDestinationUri and it even mentions for Android Q that I can use Context.getExternalFilesDir(String) . When I do this though, the path is still the emulated path:

/storage/emulated/0/Android/data/com.my.package.name/files/Download/myFile.xml

I get a callback from the download manager that the download is complete (with right ID) but then I cannot grab the download from the area I saved it to. I check to see if the file exists and it returns false:

new File("/storage/emulated/0/Android/data/com.my.package.name/files/Download/myFile.xml").exists();

Any help is appreciated

Adding code for context. So setting up download manager

    private void startDownload() {
        IntentFilter filter = new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE);
        registerReceiver(downloadReceiver, filter);

        String remoteURL= getString(R.string.remote_url);

        DownloadManager.Request request = new DownloadManager.Request(Uri.parse(remoteUrl));
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE);
        request.setTitle(getString(R.string.download_title));
        request.setDescription(getString(R.string.download_description));
        request.setDestinationUri(Uri.fromFile(new File(getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS), "myFile.xml")));

        DownloadManager manager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
        mainDownloadID= manager.enqueue(request);
    }

checking file if it exists:

new File(getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS), "myFile.xml").exists(); //this returns false in the onReceive (and download IDs match)

Answer 1

Try add this into your manifest file in application tag

android:requestLegacyExternalStorage="true"

Answer 2

Yeah Its scope storage but even though you can download file in Q+ using downloadmanger no need to do android:requestLegacyExternalStorage="true"

I am doing this way.

1. manifest

• -->

2. Downloadmanger

    val fileName = Constants.FILE_NAME + Date().time val downloadUri = Uri.parse(media.url) val request = DownloadManager.Request( downloadUri ) request.setAllowedNetworkTypes( DownloadManager.Request.NETWORK_WIFI or DownloadManager.Request.NETWORK_MOBILE ) .setAllowedOverRoaming(true).setTitle("Some name") .setDescription("Downloading file") .setDestinationInExternalPublicDir( Environment.DIRECTORY_DOWNLOADS, File.separator + FOLDER + File.separator + fileName ) Toast.makeText( context, "Download successfully to ${downloadUri?.path}", Toast.LENGTH_LONG ).show() downloadManager.enqueue(request)

Hence it will ask write permission below Q, but in Q and Q+ it will download without asking permission in /Download/folder dir.

Answer 3

File Paths outside of the App's private directories in Android Q and above useless.

See https://developer.android.com/training/data-storage#scoped-storage

You need to ask the user where to download the files too, this will get you a URI for the DownloadManager destination.

https://developer.android.com/training/data-storage/shared/documents-files#grant-access-directory

You will probably want to persist this permission

https://developer.android.com/training/data-storage/shared/documents-files#persist-permissions

Answer 4

Use this code and enjoy, this code uses RxJava for network call:

import android.content.ContentValues
import android.content.Context
import android.os.Build
import android.os.Environment
import android.provider.MediaStore
import io.reactivex.Observable
import io.reactivex.ObservableEmitter
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.ResponseBody
import java.io.*
import java.net.HttpURLConnection
import java.util.concurrent.TimeUnit

    class FileDownloader(
         private val context: Context,
         private val url: String,
         private val fileName: String
         ) {
    
        private val okHttpClient: OkHttpClient = OkHttpClient.Builder()
            .connectTimeout(60, TimeUnit.SECONDS)
            .readTimeout(60, TimeUnit.SECONDS)
            .build()
    
        private val errorMessage = "File couldn't be downloaded"
        private val bufferLengthBytes: Int = 1024 * 4
    
        fun download(): Observable<Int> {
            return Observable.create<Int> { emitter ->
    
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) { // To Download File for Android 10 and above
                    val content = ContentValues().apply {
                        put(MediaStore.MediaColumns.DISPLAY_NAME, fileName)
                        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOWNLOADS)
                    }
                    val uri = context.contentResolver.insert(
                        MediaStore.Downloads.EXTERNAL_CONTENT_URI,
                        content
                    )
                    uri?.apply {
                        val responseBody = getResponseBody(url)
                        if (responseBody != null
                        ) {
                            responseBody.byteStream().use { inputStream ->
                                context.contentResolver.openOutputStream(uri)?.use { fileOutStream ->
                                    writeOutStream(
                                        inStream = inputStream,
                                        outStream = fileOutStream,
                                        contentLength = responseBody.contentLength(),
                                        emitter = emitter
                                    )
                                }
                                emitter.onComplete()
                            }
                        } else {
                            emitter.onError(Throwable(errorMessage))
                        }
                    }
                }
                    else { // For Android versions below than 10
                        val directory = File(
                            Environment.getExternalStoragePublicDirectory(
                                Environment.DIRECTORY_DOWNLOADS).absolutePath
                        ).apply {
                            if (!exists()) {
                                mkdir()
                            }
                        }
    
                    val file = File(directory, fileName)
                    val responseBody = getResponseBody(url)
    
                    if (responseBody != null) {
                        responseBody.byteStream().use { inputStream ->
                            file.outputStream().use { fileOutStream ->
                                writeOutStream(
                                    inStream = inputStream,
                                    outStream = fileOutStream,
                                    contentLength = responseBody.contentLength(),
                                    emitter = emitter
                                )
                            }
                            emitter.onComplete()
                        }
    
                    } else {
                        emitter.onError(Throwable(errorMessage))
                    }
                }
            }
        }
    
        private fun getResponseBody(url: String): ResponseBody? {
            val response = okHttpClient.newCall(Request.Builder().url(url).build()).execute()
    
            return if (response.code >= HttpURLConnection.HTTP_OK &&
                response.code < HttpURLConnection.HTTP_MULT_CHOICE &&
                response.body != null
            )
                response.body
            else
                null
        }
    
        private fun writeOutStream(
            inStream: InputStream,
            outStream: OutputStream,
            contentLength: Long,
            emitter: ObservableEmitter<Int>) {
                var bytesCopied = 0
                val buffer = ByteArray(bufferLengthBytes)
                var bytes = inStream.read(buffer)
                while (bytes >= 0) {
                    outStream.write(buffer, 0, bytes)
                    bytesCopied += bytes
                    bytes = inStream.read(buffer)
    //                emitter.onNext(
                        ((bytesCopied * 100) / contentLength).toInt()
    //                )
                }
        outStream.flush()
        outStream.close()
    
        }
    }

On calling side you've to right this:

private fun downloadFileFromUrl(context: Context, url: String, fileName: String) {
    FileDownloader(
        context = context,
        url = url,
        fileName = fileName
    ).download()
        .throttleFirst(2, TimeUnit.SECONDS)
        .toFlowable(BackpressureStrategy.LATEST)
        .subscribeOn(Schedulers.io())
        .observeOn(mainThread())
        .subscribe({
            // onNext: Downloading in progress
        }, { error ->
            // onError: Download Error
            requireContext()?.apply {
                Toast.makeText(this, error.message, Toast.LENGTH_SHORT).show()
            }
        }, {
            // onComplete: Download Complete
            requireContext()?.apply {
                Toast.makeText(this, "File downloaded to Downloads Folder", Toast.LENGTH_SHORT).show()
            }
        })
}