無法解碼流：java.io.FileNotFoundException：

Question

我有一個可以拍照的應用程序。我最近不得不更改所述應用程序的一部分，因爲不再能夠通過意圖傳遞URI。所以我改變了我的代碼部分來自

file_uri = Uri.fromFile(file);

到

file_uri = FileProvider.getUriForFile(PhotoActivity.this,BuildConfig.APPLICATION_ID + ".provider", file);

但是現在這似乎已經打破了我的代碼另一部分，我無法弄清楚如何解決它。

這是有關部分：

private class Encode_image extends AsyncTask<Void, Void, Void> { 
    @Override 
    protected Void doInBackground(Void... voids) { 

     bitmap = BitmapFactory.decodeFile(file_uri.getPath()); 

     ByteArrayOutputStream stream = new ByteArrayOutputStream(); 
     bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream); 
     bitmap.recycle(); 

     byte[] array = stream.toByteArray(); 
     encoded_string = Base64.encodeToString(array, 0); 
     return null; 
    } 

    @Override 
    protected void onPostExecute(Void aVoid) { 
     makeRequest(); 
    } 
} 
private void makeRequest() { 

    RequestQueue requestQueue = Volley.newRequestQueue(this); 
    StringRequest request = new StringRequest(Request.Method.POST, POST_URL, 
      new Response.Listener<String>() { 
       @Override 
       public void onResponse(String response) { 

       } 
      }, new Response.ErrorListener() { 
     @Override 
     public void onErrorResponse(VolleyError error) { 

     } 
    }) { 
     @Override 
     protected Map<String, String> getParams() throws AuthFailureError { 
      HashMap<String,String> map = new HashMap<>(); 
      map.put("encoded_string",encoded_string); 
      map.put("image_name",image_name); 

      return map; 
     } 
    }; 
    requestQueue.add(request); 
} 

private void getFileUri() { 

    String uuid = UUID.randomUUID().toString(); 
    imageName=uuid; 

    image_name = uuid + ".jpg"; 
    file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) 
      + File.separator + image_name 
    ); 

    //file_uri = Uri.fromFile(file); 
    file_uri = FileProvider.getUriForFile(PhotoActivity.this, 
      BuildConfig.APPLICATION_ID + ".provider", 
      file); 
} 

，這是錯誤我得到：

E/BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /external_files/Pictures/aba094a2-3f15-405f-9203-fdc4245dc003.jpg (No such file or directory) 
E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1 
                       Process: com.example.gabrieluliano.my_sick_app, PID: 8639 
                       java.lang.RuntimeException: An error occurred while executing doInBackground() 
                        at android.os.AsyncTask$3.done(AsyncTask.java:318) 
                        at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354) 
                        at java.util.concurrent.FutureTask.setException(FutureTask.java:223) 
                        at java.util.concurrent.FutureTask.run(FutureTask.java:242) 
                        at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243) 
                        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133) 
                        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607) 
                        at java.lang.Thread.run(Thread.java:762) 
                        Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.compress(android.graphics.Bitmap$CompressFormat, int, java.io.OutputStream)' on a null object reference 
                        at com.example.gabrieluliano.my_sick_app.PhotoActivity$Encode_image.doInBackground(PhotoActivity.java:347) 
                        at com.example.gabrieluliano.my_sick_app.PhotoActivity$Encode_image.doInBackground(PhotoActivity.java:331) 
                        at android.os.AsyncTask$2.call(AsyncTask.java:304) 
                        at java.util.concurrent.FutureTask.run(FutureTask.java:237) 
                        at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)  
                        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)  
                        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)  
                        at java.lang.Thread.run(Thread.java:762)  

任何人都知道什麼是錯的呢？感謝

編輯： 我改變了位圖部分：

try(InputStream is = new URL(file_uri.getPath()).openStream()){ 
     bitmap = BitmapFactory.decodeStream(is); 

     ByteArrayOutputStream stream = new ByteArrayOutputStream(); 
     bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream); 
     bitmap.recycle(); 

     byte[] array = stream.toByteArray(); 
     encoded_string = Base64.encodeToString(array, 0); 
     return null; 
     } 
     catch(Exception e){ 
      return null; 
     } 

Answer 1

bitmap = BitmapFactory.decodeFile(file_uri.getPath()); 

變化

bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(file_uri)); 

但是，當然，這是不好使一個位圖出來的文件第一次。

您當然應該上傳文件'原樣'，而不要搞亂Bitmaps和BitmapFactory。

Answer 2

嘗試使用BitmapFactory.decodeStream而非BitmapFactory.decodeFile。

Here是如何使用它的一個例子。