Question

我正在尝试获取文件的路径以便阅读它。

这是我点击按钮时的代码我用当前视图启动OnBrowse()：

public void onBrowse(View view) {
        Intent chooseFile;
        Intent intent;
        chooseFile = new Intent(Intent.ACTION_GET_CONTENT);
        chooseFile.addCategory(Intent.CATEGORY_OPENABLE);
        chooseFile.setType("*/*");
        intent = Intent.createChooser(chooseFile, "Choose a file");
        startActivityForResult(intent, ACTIVITY_CHOOSE_FILE);
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != RESULT_OK) return;
        String path     = "";
        if(requestCode == ACTIVITY_CHOOSE_FILE)
        {
            Uri uri = data.getData();
            Log.d("Path", ""+uri);
            File myFile = new File(uri.getPath());
            myFile.getAbsolutePath();
            loadFile(myFile.getAbsolutePath());
        }
    }

    public String getRealPathFromURI(Uri contentUri) {
        String [] proj      = {MediaStore.Images.Media.DATA};
        Cursor cursor       = getContentResolver().query( contentUri, proj, null, null,null);
        if (cursor == null) return null;
        int column_index    = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
    }

Noe一切正常，但myFile.getAbsolutePath()给了我以下路径：

/document/raw:/storage/emulated/0/Download/File.txt

当我认为它应该只返回storage/emulated/0/Download/File.txt

时

因此，当我尝试阅读该文件时，它会引发异常。

由于

Answer 1

你应该将URI转换为字符串路径，尝试下面的代码

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

    final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;

    // DocumentProvider
    if (isKitKat && 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 getDataColumn(context, uri, null, null);
    }
    // File
    else if ("file".equalsIgnoreCase(uri.getScheme())) {
        return uri.getPath();
    }

    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());
}

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 column_index = cursor.getColumnIndexOrThrow(column);
            return cursor.getString(column_index);
        }
    } finally {
        if (cursor != null)
            cursor.close();
    }
    return null;
}

Answer 2

如果您只想阅读uri的内容，则使用Inputstream而不是文件会容易得多。无需翻译成文件。这也适用于http和ftp uri-s

InputStream in = getContentResolver().openInputStream(uri);
loadFromInputStream(in);

有关详细信息，请参阅sdk ContentResolver#openInputStream(uri)

Uri得到错误的文件路径

2 个答案: