Question

我需要将图像发送到服务，预执行方法的工作方式与后台工作方式不同。代码如下：

    private class SendImageAsync extends AsyncTask<String, String, String> {
        private Context context;
        private String serverUrl;
        private String path;

        public SendImageAsync(Context context, String serverUrl,
                 String path) {
            this.context = context;
            this.serverUrl = serverUrl;
            this.path = path;
        }

        @Override
        protected void onPreExecute() {
            LogWrite.i(TAG, "onPreExecute method enters!!");

            super.onPreExecute();
        }

        @Override
        protected String doInBackground(String... params) {
            LogWrite.i(TAG, "doInBackground method enters!!");
            byte[] imageBytes = getFileBytes(path);
            ImageToSend sendImage = new ImageToSend();
            boolean responseStatus = sendImage.send(context, serverUrl,
                    imageBytes );
            String responseString = responseStatus ? "Success!" : "Fail!";
            LogWrite.e(TAG, "Response " + responseString);
            return "";
        }

        @Override
        protected void onPostExecute(String result) {
            LogWrite.i(TAG, "onPostExecute method enters!!");
            super.onPostExecute(result);
        }
    }

请帮助我，为什么它不起作用？

更新代码：我创建了一个界面，它将在图像点击时通知我并提供文件路径：

@Override
public void onImageCapture(File file) {
    if (file != null) {
        LogWrite.d(TAG, "File Path ::: " + file.getAbsolutePath());
        if (isFromCommand) {
            LogWrite.d(TAG, "Is from command : "+ isFromCommand);
            try {
                SendImageAsync async = new SendImageAsync (activity,
                        serverUrl, file.getAbsolutePath());
                async.execute("");
            } catch (Exception e) {
                LogWrite.e(TAG, "SendImageAsync Exception : " + e.toString());
            }

        }
        Bitmap myBitmap = showBitmapFromFile(file.getAbsolutePath());
        myBitmap = RotateBitmap(myBitmap, 90);

        Drawable ob = new BitmapDrawable(getResources(), myBitmap);
        saveImageView.setBackgroundDrawable(ob);
    } 
    // saveImageView.setImageBitmap(myBitmap);
}

Answer 1

我不确定，但您可能想发送请求而不是回复...

Answer 2

我找到了解决方案，我在另一个AsyncTask上使用了这个AsyncTask，所以它不起作用，即使它没有给出任何例外。

Answer 3

以下是您可以参考的基本示例代码，希望此帮助

/**
 * Async task to post file to remote web api
 */
public class PostFileToWebAPI extends AsyncTask<String, Integer, Object> {    

   ...

    @Override
    protected Object doInBackground(String... params) {
        String filePath = params[1];
        try {                               
            return postFile(mAPI_URL, filePath);
        } catch (Exception e) {
            return e.getMessage();
        }
    }

    @Override
    protected void onPostExecute(Object o) {
        super.onPostExecute(o);            
    }      
}


private String postFile(String apiUrl, String filePath) throws Exception {
    // init httpClient, httpPost...
    ...

    MultipartEntityBuilder builder = MultipartEntityBuilder.create();
    builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
    File file = new File(filePath);
    FileBody fileBody = new FileBody(file);
    final long totalSize = fileBody.getContentLength();
    builder.addPart("file", fileBody);        
    httpEntity = builder.build();      
    httpPost.setEntity(httpEntity);
    httpResponse = httpClient.execute(httpPost);
    statusCode = httpResponse.getStatusLine().getStatusCode();

    if ((statusCode != HttpStatus.SC_OK) && (statusCode != HttpStatus.SC_INTERNAL_SERVER_ERROR)) {
        return httpResponse.getStatusLine().toString();
    } else {
        return getStringContent(httpResponse);
    }
}

将图像发送到服务器时异步不起作用？

3 个答案: