作为一个附加组件，如果在尝试打开输入流之前需要查看文件是否存在，可以使用DocumentsContract。

(Kotlin代码)

var iStream = null
if(DocumentsContract.isDocumentUri(context,myUri)) {
   val pfd: ParcelFileDescriptor? = context.contentResolver.openFileDescriptor(
            myUri, "r") ?: return null
   iStream = ParcelFileDescriptor.AutoCloseInputStream(pfd)
}

我用一行代码做到这一点:

val bitmap = MediaStore.Images.Media。getBitmap (contentResolver uri)

在onActivityResult中看起来是这样的:

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    if (resultCode == Activity.RESULT_OK && requestCode == REQUEST_CODE_IMAGE_PICKER ) {
        data?.data?.let { imgUri: Uri ->
            val bitmap = MediaStore.Images.Media.getBitmap(contentResolver, imgUri)
        }
    }
}

如果你的系统版本在19以上，这对我来说是完美的，希望这能帮助你。

  @TargetApi(Build.VERSION_CODES.KITKAT)
    public static String getPath(final Context context, final Uri uri) {
        final boolean isOverKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
        // DocumentProvider
        if (isOverKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            // ExternalStorageProvider
            if (isExternalStorageDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/"
                            + split[1];
                }
            }
            // DownloadsProvider
            else if (isDownloadsDocument(uri)) {
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(
                        Uri.parse("content://downloads/public_downloads"),
                        Long.valueOf(id));
                return getDataColumn(context, contentUri, null, null);
            }
            // MediaProvider
            else if (isMediaDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }
                final String selection = "_id=?";
                final String[] selectionArgs = new String[]{split[1]};
                return getDataColumn(context, contentUri, selection,
                        selectionArgs);
            }
        }
        // MediaStore (and general)
        else if ("content".equalsIgnoreCase(uri.getScheme())) {
            // Return the remote address
            if (isGooglePhotosUri(uri))
                return uri.getLastPathSegment();
            return getDataColumn(context, uri, null, null);
        }
        // File
        else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }
        return null;
    }

由于managedQuery已弃用，您可以尝试:

CursorLoader cursorLoader = new CursorLoader(context, uri, proj, null, null, null);
Cursor cursor = cursorLoader.loadInBackground();

对于那些搬到奇巧后有问题的人:

这将从MediaProvider, DownloadsProvider和ExternalStorageProvider获取文件路径，同时回落到非官方的ContentProvider方法https://stackoverflow.com/a/20559175/690777

我是这样做的:

    Uri queryUri = MediaStore.Files.getContentUri("external");
    String columnData = MediaStore.Files.FileColumns.DATA;
    String columnSize = MediaStore.Files.FileColumns.SIZE;

    String[] projectionData = {MediaStore.Files.FileColumns.DATA};


    String name = null;
    String size = null;

    Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
    if ((cursor != null)&&(cursor.getCount()>0)) {
        int nameIndex = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
        int sizeIndex = cursor.getColumnIndex(OpenableColumns.SIZE);

        cursor.moveToFirst();

        name = cursor.getString(nameIndex);
        size = cursor.getString(sizeIndex);

        cursor.close();
    }

    if ((name!=null)&&(size!=null)){
        String selectionNS = columnData + " LIKE '%" + name + "' AND " +columnSize + "='" + size +"'";

        Cursor cursorLike = getContentResolver().query(queryUri, projectionData, selectionNS, null, null);

        if ((cursorLike != null)&&(cursorLike.getCount()>0)) {
            cursorLike.moveToFirst();
            int indexData = cursorLike.getColumnIndex(columnData);
            if (cursorLike.getString(indexData) != null) {
                result = cursorLike.getString(indexData);
            }
            cursorLike.close();
        }
    }

    return result;