将字符串路径转换为输入流

Question

我正在使用Quickblox聊天API开发一个聊天应用程序，目前已完成用户注册、身份验证以及基本的点对点聊天和群聊。现在正在实现视频、图像和文件发送，但某些部分遇到了困难。

1. Selecting image from sd card. returns picture path in string and its not converting to inputStream. Have tried for about 10-15 answers on SOF. My code is as follows:

       Intent i = new Intent(Intent.ACTION_PICK,
               android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
   
       startActivityForResult(i, RESULT_LOAD_IMAGE);
   

   protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data);

   if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
   
   
       Uri selectedImage = data.getData();
       String[] filePathColumn = { MediaStore.Images.Media.DATA };
   
       Cursor cursor = getContentResolver().query(selectedImage,
               filePathColumn, null, null, null);
       cursor.moveToFirst();
   
       int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
       String picturePath = cursor.getString(columnIndex);
       cursor.close();
   
       Bitmap imagebitmap=BitmapFactory.decodeFile(picturePath);
   
       byte[] b=picturePath.getBytes(Charset.forName("UTF-8"));
   
       InputStream is = new ByteArrayInputStream(b);
   
       File newFile = FileHelper.getFileInputStream(is, "sample.jpg", "myFile");
   
       Boolean fileIsPublic = false;
   
       QBContent.uploadFileTask(newFile, fileIsPublic, null, new QBEntityCallbackImpl<QBFile>()
               {
           public void onSuccess(QBFile file, Bundle params) {
   
               //creating message
   
               QBChatMessage chatmessage=new QBChatMessage();
               chatmessage.setProperty("save_to_history", "1");    //saves messsage to history
   
               QBAttachment qbAttachment=new QBAttachment("photo");
               qbAttachment.setId(file.getId().toString());
   
               chatmessage.addAttachment(qbAttachment);
   
               try
               {
                   chat.sendMessage(chatmessage);
   
                   Toast.makeText(getApplicationContext(), "Image Uploaded Successfully", Toast.LENGTH_SHORT).show();
   
               } catch (XMPPException e) {
                   Log.e(TAG, "failed to send a image", e);
               } catch (SmackException sme){
                   Log.e(TAG, "failed to send a image", sme);
               }
   
           }
   
           public void onError(java.util.List<String> errors) {
   
               AlertDialog.Builder dialog = new AlertDialog.Builder(ChatActivity.this);
               dialog.setMessage("error when sending image: " + errors.toString()).create().show();
   
   
           };});}
   

我尝试了以下代码以生成InputStream：

1. InputStream is = new ByteArrayInputStream(picturePath.toString().getBytes(Charset.defaultCharset()));

2. try { is = IOUtils.toInputStream(picturePath, "UTF-8"); } catch (IOException e1) { // TODO Auto-generated catch block e1.printStackTrace(); }

这段代码会在myfile文件夹中生成新的sample.jpg文件，但实际上并没有创建成功，反而出现了错误。但如果我选择静态图片，则代码能够完美地工作。

非常感谢您提前的帮助，我不知道我哪里做错了...非常感激任何形式的帮助。

- SK16

---

你的目标版本是什么？ - vojta

这可能是你的问题：https://dev59.com/Gl8d5IYBdhLWcg3wgya4 - vojta

@vojta...所以新文件系统限制了我进行修改？我会看一下的... - SK16

请参考此答案 https://dev59.com/tIjca4cB1Zd3GeqPsSf1#28739568 - Amrut Bidri

Answer 1

经过大量的努力和代码更改，我完成了我所需要的。我使用ByteArrayInputStream而不是inputstream。首先将我的字符串picturepath转换为位图（不知道为什么要这样做...但做了），然后使用以下代码将该位图转换为ByteArrayInputStream：

ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
        imagebitmap.compress(CompressFormat.PNG, 0 /*ignored for PNG*/, bos); 
        byte[] bitmapdata = bos.toByteArray();
        ByteArrayInputStream bs = new ByteArrayInputStream(bitmapdata);

并将结果发送到我的函数……成功了！！！

- SK16