由DocumentsUI 得到文件path

uriForCapture = content://com.android.PRoviders.media.documents/document/video%3A98

uriForCapture = content://media/external/video/media/98

针对这2中uri第二种通过查多媒体数据库很容易得到文件path，类似：uriString = /storage/emulated/0/DCIM/Camera/***.mp4

但是第一种不能直接查询到。

可以尝试以下方法：

      private String getPathFromDocmentsUri(Context ctx,Uri docUri) {       String imagePath = null;

       if (DocumentsContract.isDocumentUri(ctx, docUri)) {            String docId = DocumentsContract.getDocumentId(docUri);            if ("com.android.providers.media.documents".equals(docUri.getAuthority())) {                String id = docId.split(":")[1];                //String selection = MediaStore.Video.Media._ID + "=" + id;                imagePath = getPathFromDoc(MediaStore.Video.Media.EXTERNAL_CONTENT_URI.toString()+"/"+id);            } else if ("com.android.providers.downloads.documents".equals(docUri.getAuthority())) {                Uri contentUri = ContentUris.withAppendedId(                        Uri.parse("content://downloads/public_downloads"),                        Long.valueOf(docId));                imagePath = getPathFromDoc(contentUri.toString());            }        }       return imagePath;    }

    private String getPathFromDoc(String docUri) {        String imagePath = null;        Log.d(TAG, "getPathFromDoc ,imageUrl= " + docUri);        Uri uri = Uri.parse(docUri);        String[] proj = { MediaStore.Images.Media.DATA };        Cursor imageCursor = mContext.getContentResolver().query(uri, proj, null, null, null);

        if (imageCursor != null) {            if (imageCursor.moveToFirst()) {                int image_column_index = imageCursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);                imagePath = imageCursor.getString(image_column_index);            }            imageCursor.close();        }        return imagePath;    }