我想在另一个方法中使用方法的返回？

Question

我想在其他方法中使用请求http“result”（方法获取数据）的返回来创建包含在文件名中的结果的文件名。 谢谢你的帮助

first method
 public void getData(){
        class GetDataJSON extends AsyncTask<String, Void, String> {

            @Override
            protected String doInBackground(String... params) {
                DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
                HttpPost httppost = new HttpPost("http://192.168.x.x/x/id1.php");

                // Depends on your web service


                InputStream inputStream = null;
               String result = null;
                try {
                    HttpResponse response = httpclient.execute(httppost);
                    HttpEntity entity = response.getEntity();

                    inputStream = entity.getContent();
                    // json is UTF-8 by default
                    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
                    StringBuilder sb = new StringBuilder();

                    String line = null;
                    while ((line = reader.readLine()) != null)
                    {
                        sb.append(line + "\n");

                    }
                    result = sb.toString();
                } catch (Exception e) {
                    // Oops
                }
                finally {
                    try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
                }
                return result;
            }

            @Override
            protected void onPostExecute(String  result){
                 myJSON =result;

            }
        }
        GetDataJSON g = new GetDataJSON();
        g.execute();
    }

第二种方法

  private static File getOutputMediaFile(int type) {

            // External sdcard location
            File mediaStorageDir = new File(
                    Environment
                            .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
                    Config.IMAGE_DIRECTORY_NAME);

            // Create the storage directory if it does not exist
            if (!mediaStorageDir.exists()) {
                if (!mediaStorageDir.mkdirs()) {
                    Log.d(TAG, "Oops! Failed create "
                            + Config.IMAGE_DIRECTORY_NAME + " directory");
                    return null;
                }
            }

            // Create a media file name  
            String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
                    Locale.getDefault()).format(new Date());
            File mediaFile
    //i want to use it here like "IMG_VG"+result+...
            if (type == MEDIA_TYPE_IMAGE) {

                mediaFile = new File(mediaStorageDir.getPath() + File.separator
                        + "IMG_VG" + timeStamp + ".jpg");
            } else if (type == MEDIA_TYPE_VIDEO) {
                mediaFile = new File(mediaStorageDir.getPath() + File.separator
                        + "VID_VG" + timeStamp + ".mp4");
            } else {
                return null;
            }

            return mediaFile;
        }

Answer 1

为什么不在AsyncTask中使用第二种方法？它不是返回下载的数据，而是返回一个从'doInBackground'方法中的数据创建的文件。然后将文件返回到'onPostExecute'中的Activity。

 public void getData(){
    class GetDataJSON extends AsyncTask<String, Void, File> {

        @Override
        protected File doInBackground(String... params) {
            DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
            HttpPost httppost = new HttpPost("http://192.168.x.x/x/id1.php");

            // Depends on your web service


            InputStream inputStream = null;
            File outputFile = getOutputMediaFile(0);
           String result = null;
            try {
                HttpResponse response = httpclient.execute(httppost);
                HttpEntity entity = response.getEntity();
                //TODO check if result is 200 OK or you'll write the error in the file.

                inputStream = entity.getContent();

                // json is UTF-8 by default
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
                StringBuilder sb = new StringBuilder();

                String line = null;
                while ((line = reader.readLine()) != null)
                {
                    sb.append(line + "\n");

                }
                result = sb.toString();

                FileWriter writer = new FileWriter(outputFile);
                writer.write(result);
                writer.close();
                return outputFile;
            } catch (Exception e) {
                // Oops
            }
            finally {
                try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
            }
            return outputFile;
        }

        @Override
        protected void onPostExecute(File  result){
             myFile =result;

        }
    }
    GetDataJSON g = new GetDataJSON();
    g.execute();
}