Android用ACTION_GET_CONTENT打开一个文件导致不同的Uri

Question

我试图通过使用打开文件Intent.ACTION_GET_CONTENT.

根据Android版本/设备品牌,文件浏览器打开,我得到以下结果:

从Downloads以下位置选择文件:

content://com.android.providers.downloads.documents/document/446

从Fotos以下位置选择文件:

content://media/external/images/media/309

从FileCommander以下位置选择文件:

file:///storage/emulated/0/DCIM/Camera/20141027_132114.jpg

我可以打开所有这些文件除了当我尝试打开从文件Downloads,,Audio,Afbeeldingen(图片)

我可能无法处理这种Uri: content://com.android.providers.downloads.documents/document/446

我试过以下的事情:

• 尝试通过新文件(uri.getPath())打开文件.File.exists()返回false.
• 尝试通过getContext().getContentResolver().openInputStream(uri)打开/访问该文件.结果进入FileNotFoundException

• 尝试使用以下代码打开文件:

  public static String getRealPathFromURI_API19(Context context, Uri uri) {
  
  Log.i("uri", uri.getPath());
  String filePath = "";
  if (uri.getScheme().equals("file")) {
      return uri.getPath();
  } else if (DocumentsContract.isDocumentUri(context, uri)) {
      String wholeID = DocumentsContract.getDocumentId(uri);
      Log.i("wholeID", wholeID);
      // Split at colon, use second item in the array
      String[] splits = wholeID.split(":");
  if (splits.length == 2) {
      String id = splits[1];
  
          String[] column = {MediaStore.Images.Media.DATA};
      // where id is equal to
          String sel = MediaStore.Images.Media._ID + "=?";
          Cursor cursor = context.getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                  column, sel, new String[]{id}, null);
          int columnIndex = cursor.getColumnIndex(column[0]);
          if (cursor.moveToFirst()) {
              filePath = cursor.getString(columnIndex);
          }
          cursor.close();
      }
  } else {
      filePath = AttachmentUtils.getPath(context, uri);
  }
  return filePath;
  }
  

我究竟做错了什么？

更新:我注意到屏幕截图中列出的文件实际上并不存在于存储中.我使用的设备是包含垃圾数据的公司平板电脑.我的同事告诉我,此设备曾与其他Google帐户关联.这些文件可能是以前帐户中不再存在/可访问的文件.

我自己的结论是我在Android中遇到了一些错误.我的错误报告

2017年2月6日更新:

Android禁止了file://URI.请考虑考虑一下.

禁止存档:Uri Scheme到目前为止,Android 7.0最大的兼容性问题是Uri值的文件:scheme实际上是禁止的.如果你试图传递一个文件:Uri在一个转到另一个应用程序的Intent中 - 无论是通过额外的还是作为Intent的"数据"方面 - 你将崩溃并发生FileUriExposedException异常.将文件放在剪贴板中的剪贴板上的Uri值将面临类似的问题.这来自StrictMode的更新版本.StrictMode.VmPolicy.Builder有一个penaltyDeathOnFileUriExposure()方法,它触发文件的检测:Uri值和生成的FileUriExposedException异常.并且,它似乎是预先配置的,就像StrictMode预先配置为应用penaltyDeathOnNetwork()(NetworkOnMainThreadException的崩溃源)一样.

Answer 1

使用下面的代码.这将是肯定的.

public static String getPath(Context context, Uri uri) {

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
        // DocumentProvider
        if (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];
                }
                // TODO handle non-primary volumes
            }
            // 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;
}

public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
    Cursor cursor = null;
    final String column = "_data";
    final String[] projection = {column};
    try {
        cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
        if (cursor != null && cursor.moveToFirst()) {
            final int index = cursor.getColumnIndexOrThrow(column);
            return cursor.getString(index);
        }
    } finally {
        if (cursor != null)
            cursor.close();
    }
    return null;
}

public static boolean isExternalStorageDocument(Uri uri) {
    return "com.android.externalstorage.documents".equals(uri.getAuthority());
}

/**
 * @param uri The Uri to check.
 * @return Whether the Uri authority is DownloadsProvider.
 */
public static boolean isDownloadsDocument(Uri uri) {
    return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}

/**
 * @param uri The Uri to check.
 * @return Whether the Uri authority is MediaProvider.
 */
public static boolean isMediaDocument(Uri uri) {
    return "com.android.providers.media.documents".equals(uri.getAuthority());
}

/**
 * @param uri The Uri to check.
 * @return Whether the Uri authority is Google Photos.
 */
public static boolean isGooglePhotosUri(Uri uri) {
    return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}

使用以下代码以任何格式浏览文件.

public void browseClick() {

    Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
    intent.setType("*/*");
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    //intent.putExtra("browseCoa", itemToBrowse);
    //Intent chooser = Intent.createChooser(intent, "Select a File to Upload");
    try {
        //startActivityForResult(chooser, FILE_SELECT_CODE);
        startActivityForResult(Intent.createChooser(intent, "Select a File to Upload"),FILE_SELECT_CODE);
    } catch (Exception ex) {
        System.out.println("browseClick :"+ex);//android.content.ActivityNotFoundException ex
    }
}

然后在onActivityResult中获取该文件路径,如下所示.

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == FILE_SELECT_CODE) {
        if (resultCode == RESULT_OK) {
            try {
              Uri uri = data.getData();

                if (filesize >= FILE_SIZE_LIMIT) {
                    Toast.makeText(this,"The selected file is too large. Selet a new file with size less than 2mb",Toast.LENGTH_LONG).show();
                } else {
                    String mimeType = getContentResolver().getType(uri);
                    if (mimeType == null) {
                        String path = getPath(this, uri);
                        if (path == null) {
                            filename = FilenameUtils.getName(uri.toString());
                        } else {
                            File file = new File(path);
                            filename = file.getName();
                        }
                    } else {
                        Uri returnUri = data.getData();
                        Cursor returnCursor = getContentResolver().query(returnUri, null, null, null, null);
                        int nameIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
                        int sizeIndex = returnCursor.getColumnIndex(OpenableColumns.SIZE);
                        returnCursor.moveToFirst();
                        filename = returnCursor.getString(nameIndex);
                        String size = Long.toString(returnCursor.getLong(sizeIndex));
                    }
   File fileSave = getExternalFilesDir(null);
    String sourcePath = getExternalFilesDir(null).toString();
    try {
                        copyFileStream(new File(sourcePath + "/" + filename), uri,this);

                    } catch (Exception e) {
                        e.printStackTrace();
                    }
  }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
private void copyFileStream(File dest, Uri uri, Context context)
        throws IOException {
    InputStream is = null;
    OutputStream os = null;
    try {
        is = context.getContentResolver().openInputStream(uri);
        os = new FileOutputStream(dest);
        byte[] buffer = new byte[1024];
        int length;

        while ((length = is.read(buffer)) > 0) {
            os.write(buffer, 0, length);

        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        is.close();
        os.close();
    }
}

在此之后,您可以从应用程序外部存储中打开此文件,并使用适当的操作保存文件.