访问ActivityResult Android 28 Samsung Galaxy S9+(Verizon)上的公共下载文件

我是如何决定修改getPath的isDownloadDirectory路径流的。我还不知道所有的连锁反应,虽然QA将在明天开始,我会更新,如果我从这学到什么新的东西。

使用direct URI获取文件名的contentResolver(注意*这不是获取文件名的好方法,除非根据Google,您确定它是本地文件,但对我来说,我确定它是下载的。)

private val PUBLIC_DOWNLOAD_PATH = "content://downloads/public_downloads"
private val EXTERNAL_STORAGE_DOCUMENTS_PATH = "com.android.externalstorage.documents"
private val DOWNLOAD_DOCUMENTS_PATH = "com.android.providers.downloads.documents"
private val MEDIA_DOCUMENTS_PATH = "com.android.providers.media.documents"
private val PHOTO_CONTENTS_PATH = "com.google.android.apps.photos.content"

//HELPER METHODS
    private fun isExternalStorageDocument(uri: Uri): Boolean {
        return EXTERNAL_STORAGE_DOCUMENTS_PATH == uri.authority
    }
    private fun isDownloadsDocument(uri: Uri): Boolean {
        return DOWNLOAD_DOCUMENTS_PATH == uri.authority
    }
    private fun isMediaDocument(uri: Uri): Boolean {
        return MEDIA_DOCUMENTS_PATH == uri.authority
    }
    private fun isGooglePhotosUri(uri: Uri): Boolean {
        return PHOTO_CONTENTS_PATH == uri.authority
    }

 fun getPath(context: Context, uri: Uri): String? {
    if (DocumentsContract.isDocumentUri(context, uri)) {
        if (isExternalStorageDocument(uri)) {
            val docId = DocumentsContract.getDocumentId(uri)
            val split = docId.split(COLON.toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
            val type = split[0]
            val storageDefinition: String
            if (PRIMARY_LABEL.equals(type, ignoreCase = true)) {
                return Environment.getExternalStorageDirectory().toString() + FORWARD_SLASH + split[1]
            } else {
                if (Environment.isExternalStorageRemovable()) {
                    storageDefinition = EXTERNAL_STORAGE
                } else {
                    storageDefinition = SECONDARY_STORAGE
                }
                return System.getenv(storageDefinition) + FORWARD_SLASH + split[1]
            }
        } else if (isDownloadsDocument(uri)) {
            //val id = DocumentsContract.getDocumentId(uri) //MAY HAVE TO USE FOR OLDER PHONES, HAVE TO TEST WITH REGRESSION MODELS
            //val contentUri = ContentUris.withAppendedId(Uri.parse(PUBLIC_DOWNLOAD_PATH), id.toLong()) //SAME NOTE AS ABOVE
            val fileName = getDataColumn(context, uri, null, null)
            var uriToReturn: String? = null
            if(fileName != null){
                uriToReturn = Uri.withAppendedPath(Uri.parse(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).absolutePath), fileName).toString()
            }
            return uriToReturn
        } else if (isMediaDocument(uri)) {
            val docId = DocumentsContract.getDocumentId(uri)
            val split = docId.split(COLON.toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
            val type = split[0]
            var contentUri: Uri? = null
            if (IMAGE_PATH == type) {
                contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
            } else if (VIDEO_PATH == type) {
                contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI
            } else if (AUDIO_PATH == type) {
                contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI
            }
            val selection = "_id=?"
            val selectionArgs = arrayOf(split[1])
            return getDataColumn(context, contentUri!!, selection, selectionArgs)
        }
    } else if (CONTENT.equals(uri.scheme, ignoreCase = true)) {
        return if (isGooglePhotosUri(uri)) uri.lastPathSegment else getDataColumn(context, uri, null, null)
    } else if (FILE.equals(uri.scheme, ignoreCase = true)) {
        return uri.path
    }
    return null
}




    private fun getDataColumn(context: Context, uri: Uri, selection: String?, selectionArgs: Array<String>?): String? {
        var cursor: Cursor? = null
        //val column = "_data" REMOVED IN FAVOR OF NULL FOR ALL   
        //val projection = arrayOf(column) REMOVED IN FAVOR OF PROJECTION FOR ALL 
        try {
            cursor = context.contentResolver.query(uri, null, selection, selectionArgs, null)
            if (cursor != null && cursor.moveToFirst()) {
                val columnIndex = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_DISPLAY_NAME) //_display_name
                return cursor.getString(columnIndex) //returns file name
            }
        }catch (ex: Exception){
            A35Log.e(SSGlobals.SEARCH_STRING + "PathUtils", "Error getting uri for cursor to read file: ${ex.message}")
        } finally {
            if (cursor != null)
                cursor.close()
        }
        return null
    }

我的解决方案不同 我正在尝试获取路径,以便可以将文件复制到我的应用程序文件夹。 在没有找到答案之后,我尝试了以下方法。

           // DownloadsProvider
            else if (IsDownloadsDocument(uri))
            {
                if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
                {
                    //Hot fix for android oreo
                    bool res = MediaService.MoveAssetFromURI(uri, ctx, ref error);
                    return res ? "copied" : null;
                }
                else
                {
                    string id = DocumentsContract.GetDocumentId(uri);

                    Android.Net.Uri contentUri = ContentUris.WithAppendedId(
                                    Android.Net.Uri.Parse("content://downloads/public_downloads"), long.Parse(id));

                    //System.Diagnostics.Debug.WriteLine(contentUri.ToString());

                    return GetDataColumn(ctx, contentUri, null, null);
                }
            }

 public static bool MoveAssetFromURI(Android.Net.Uri uri, Context ctx, ref string error)
    {           
        string directory = PhotoApp.App.LastPictureFolder;

        var type = ctx.ContentResolver.GetType(uri);

        string assetName = FileName(ctx, uri);

        string extension = System.IO.Path.GetExtension(assetName);

        var filename = System.IO.Path.GetFileNameWithoutExtension(assetName);

        var finalPath = $"{directory}/{filename}{extension}";

        if (File.Exists(finalPath))
        {
            error = "File already exists at the destination";
            return false;
        }

        if (extension != ".pdf" && extension == ".jpg" && extension == ".png")
        {
            error = "File extension not suported";
            return false;
        }

        using (var input = ctx.ContentResolver.OpenInputStream(uri))
        {
            using (var fileStream = File.Create(finalPath))
            {
                //input.Seek(0, SeekOrigin.Begin);
                input.CopyTo(fileStream);
            }
        }

        if (extension == ".pdf")
        {
            var imagePDFIcon = BitmapFactory.DecodeResource(ctx.Resources, Resource.Drawable.icon_pdf);

            var imagePDFPortrait = BitmapFactory.DecodeResource(ctx.Resources, Resource.Drawable.pdf_image);

            using (var stream = new FileStream($"{directory}/{filename}", FileMode.Create))
            {
                imagePDFIcon.Compress(Bitmap.CompressFormat.Jpeg, 90, stream);
            }

            using (var stream = new FileStream($"{directory}/{filename}.jpg", FileMode.Create))
            {
                imagePDFPortrait.Compress(Bitmap.CompressFormat.Jpeg, 90, stream);
            }

            return true;
        }
        else
        {
            if (extension == ".jpg" || extension == ".png")
            {
                MoveImageFromGallery(finalPath);

                File.Delete(finalPath);

                return true;
            }
        }

        return false;

因此,我没有尝试获取路径,而是创建了一个输入流,并将该流复制到我想要的位置。