Question

我有一个拍照的应用程序。由于不再能够在意图中传递URI，我最近不得不更改部分应用程序。所以我将部分代码从
file_uri = Uri.fromFile(file);

改为了
file_uri = FileProvider.getUriForFile(PhotoActivity.this,BuildConfig.APPLICATION_ID + ".provider", file);
但是现在这似乎打破了我的代码的另一部分，我无法弄清楚如何解决它。

这是相关部分：

   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);
}

这是我得到的错误：

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)

任何人都知道它有什么问题吗？感谢

编辑：我将位图部分更改为：

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

尝试使用BitmapFactory.decodeStream而不是BitmapFactory.decodeFile。

Here是如何使用它的一个示例。

Answer 2

create table practice_table
AS SELECT  table1.column1, table2.column2, count(table3.column3) ColumnAlias
FROM practice1 table1
JOIN practice2 table2 ON table1.table1ID = table2.table2ID
JOIN practice3 table3 ON table1.table1ID = table3.table3ID
where  table2.column2 in ('filter1','filter2')
GROUP BY table1.column1, t2.column2;

更改为

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

但是当然首先从文件中创建一个Bitmap并不好。

您当然应该“按原样”上传文件，而不要乱用Bitmaps和BitmapFactory。

无法解码流：java.io.FileNotFoundException：

2 个答案: