//此代码适用于2.2上的图像，不确定是否有任何其他媒体类型

   //Your file path - Example here is "/sdcard/cats.jpg"
   final String filePathThis = imagePaths.get(position).toString();

   MediaScannerConnectionClient mediaScannerClient = new
   MediaScannerConnectionClient() {
    private MediaScannerConnection msc = null;
    {
        msc = new MediaScannerConnection(getApplicationContext(), this);
        msc.connect();
    }

    public void onMediaScannerConnected(){
        msc.scanFile(filePathThis, null);
    }


    public void onScanCompleted(String path, Uri uri) {
        //This is where you get your content uri
            Log.d(TAG, uri.toString());
        msc.disconnect();
    }
   };

//此代码适用于2.2上的图像，不确定是否有任何其他媒体类型

   //Your file path - Example here is "/sdcard/cats.jpg"
   final String filePathThis = imagePaths.get(position).toString();

   MediaScannerConnectionClient mediaScannerClient = new
   MediaScannerConnectionClient() {
    private MediaScannerConnection msc = null;
    {
        msc = new MediaScannerConnection(getApplicationContext(), this);
        msc.connect();
    }

    public void onMediaScannerConnected(){
        msc.scanFile(filePathThis, null);
    }


    public void onScanCompleted(String path, Uri uri) {
        //This is where you get your content uri
            Log.d(TAG, uri.toString());
        msc.disconnect();
    }
   };

对于你的目的，公认的解决方案可能是最好的选择，但实际上要在主题行中回答问题:

在我的应用程序中，我必须从URI中获取路径，从路径中获取URI。前:

/**
 * Gets the corresponding path to a file from the given content:// URI
 * @param selectedVideoUri The content:// URI to find the file path from
 * @param contentResolver The content resolver to use to perform the query.
 * @return the file path as a string
 */
private String getFilePathFromContentUri(Uri selectedVideoUri,
        ContentResolver contentResolver) {
    String filePath;
    String[] filePathColumn = {MediaColumns.DATA};

    Cursor cursor = contentResolver.query(selectedVideoUri, filePathColumn, null, null, null);
    cursor.moveToFirst();

    int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
    filePath = cursor.getString(columnIndex);
    cursor.close();
    return filePath;
}

后者(我用于视频，但也可以用于音频或文件或其他类型的存储内容，通过替换MediaStore。音频(等)MediaStore.Video):

/**
 * Gets the MediaStore video ID of a given file on external storage
 * @param filePath The path (on external storage) of the file to resolve the ID of
 * @param contentResolver The content resolver to use to perform the query.
 * @return the video ID as a long
 */
private long getVideoIdFromFilePath(String filePath,
        ContentResolver contentResolver) {


    long videoId;
    Log.d(TAG,"Loading file " + filePath);

            // This returns us content://media/external/videos/media (or something like that)
            // I pass in "external" because that's the MediaStore's name for the external
            // storage on my device (the other possibility is "internal")
    Uri videosUri = MediaStore.Video.Media.getContentUri("external");

    Log.d(TAG,"videosUri = " + videosUri.toString());

    String[] projection = {MediaStore.Video.VideoColumns._ID};

    // TODO This will break if we have no matching item in the MediaStore.
    Cursor cursor = contentResolver.query(videosUri, projection, MediaStore.Video.VideoColumns.DATA + " LIKE ?", new String[] { filePath }, null);
    cursor.moveToFirst();

    int columnIndex = cursor.getColumnIndex(projection[0]);
    videoId = cursor.getLong(columnIndex);

    Log.d(TAG,"Video ID is " + videoId);
    cursor.close();
    return videoId;
}

基本上，MediaStore的DATA列(或您正在查询的任何子部分)存储文件路径，因此您可以使用该信息来查找它。

更新

这里假设您的媒体(图像/视频)已经添加到内容媒体提供商。如果没有，那么你将无法得到 内容URL确切地说，你想要的。取而代之的是文件Uri。

我对我的文件资源管理器活动也有同样的问题。您应该知道，文件的contenturi只支持图像、音频和视频等介质存储数据。我给你的代码获取图像内容uri从选择一个图像从sdcard。试试这个代码，也许它会为你工作…

public static Uri getImageContentUri(Context context, File imageFile) {
  String filePath = imageFile.getAbsolutePath();
  Cursor cursor = context.getContentResolver().query(
      MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
      new String[] { MediaStore.Images.Media._ID },
      MediaStore.Images.Media.DATA + "=? ",
      new String[] { filePath }, null);
  if (cursor != null && cursor.moveToFirst()) {
    int id = cursor.getInt(cursor.getColumnIndex(MediaStore.MediaColumns._ID));
    cursor.close();
    return Uri.withAppendedPath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "" + id);
  } else {
    if (imageFile.exists()) {
      ContentValues values = new ContentValues();
      values.put(MediaStore.Images.Media.DATA, filePath);
      return context.getContentResolver().insert(
          MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
    } else {
      return null;
    }
  }
}

支持android Q

public static Uri getImageContentUri(Context context, File imageFile) {
String filePath = imageFile.getAbsolutePath();
Cursor cursor = context.getContentResolver().query(
        MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
        new String[]{MediaStore.Images.Media._ID},
        MediaStore.Images.Media.DATA + "=? ",
        new String[]{filePath}, null);
if (cursor != null && cursor.moveToFirst()) {
    int id = cursor.getInt(cursor.getColumnIndex(MediaStore.MediaColumns._ID));
    cursor.close();
    return Uri.withAppendedPath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "" + id);
} else {
    if (imageFile.exists()) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            ContentResolver resolver = context.getContentResolver();
            Uri picCollection = MediaStore.Images.Media
                    .getContentUri(MediaStore.VOLUME_EXTERNAL_PRIMARY);
            ContentValues picDetail = new ContentValues();
            picDetail.put(MediaStore.Images.Media.DISPLAY_NAME, imageFile.getName());
            picDetail.put(MediaStore.Images.Media.MIME_TYPE, "image/jpg");
            picDetail.put(MediaStore.Images.Media.RELATIVE_PATH,"DCIM/" + UUID.randomUUID().toString());
            picDetail.put(MediaStore.Images.Media.IS_PENDING,1);
            Uri finaluri = resolver.insert(picCollection, picDetail);
            picDetail.clear();
            picDetail.put(MediaStore.Images.Media.IS_PENDING, 0);
            resolver.update(picCollection, picDetail, null, null);
            return finaluri;
        }else {
            ContentValues values = new ContentValues();
            values.put(MediaStore.Images.Media.DATA, filePath);
            return context.getContentResolver().insert(
                    MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
        }

    } else {
        return null;
    }
  }
}

从文件创建Content Uri内容://最简单、最健壮的方法是使用FileProvider。FileProvider提供的Uri也可以用于与其他应用程序共享文件。要从File的绝对路径获取File Uri，你可以使用DocumentFile.fromFile(new File(path, name))，它是在Api 22中添加的，对于以下版本返回null。

File imagePath = new File(Context.getFilesDir(), "images");
File newFile = new File(imagePath, "default_image.jpg");
Uri contentUri = FileProvider.getUriForFile(getContext(), "com.mydomain.fileprovider", newFile);

最好使用验证来支持Android N之前的版本，例如:

  if (Build.VERSION.SDK_INT >=  Build.VERSION_CODES.N) {
     imageUri = Uri.parse(filepath);
  } else{
     imageUri = Uri.fromFile(new File(filepath));
  }

  if (Build.VERSION.SDK_INT >=  Build.VERSION_CODES.N) {
     ImageView.setImageURI(Uri.parse(new File("/sdcard/cats.jpg").toString()));         
  } else{
     ImageView.setImageURI(Uri.fromFile(new File("/sdcard/cats.jpg")));
  }

https://es.stackoverflow.com/questions/71443/reporte-crash-android-os-fileuriexposedexception-en-android-n