Android低连接取消异步http任务

Question

我有一个前台服务，可以从服务器运行我所有的上传/下载媒体文件（音频、视频、图片）。对于纯文本消息，我使用 AsyncTask 将消息发送到服务器。 在上传或下载消息时，我会在消息旁边显示一个进度条。

有人告诉我，在使用该应用程序时，有时短信很长时间没有通过，并且进度条一直在旋转。 这就是我为所有 http 请求获取默认 httpclient 的方式。

private static DefaultHttpClient httpclient;  // my static httpclient

 public synchronized static DefaultHttpClient getNewHttpClient() {
    if(httpclient!=null){
        Log.d(TAG, "returning existing httpclient");
        return httpclient;      
    }

    try {
        Log.d(TAG, "creating new httpclient");

        KeyStore trustStore = KeyStore.getInstance(KeyStore
                .getDefaultType());
        trustStore.load(null, null);

        SSLSocketFactory sf = new SixDegreeSSLSocketFactory(trustStore);
        sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);

        HttpParams params = new BasicHttpParams();
        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
        HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);


        SchemeRegistry registry = new SchemeRegistry();
        registry.register(new Scheme("http", PlainSocketFactory
                .getSocketFactory(), 80));
        registry.register(new Scheme("https", sf, 443));

        HttpConnectionParams.setConnectionTimeout(params, 6 * 1000);
        ClientConnectionManager ccm = new ThreadSafeClientConnManager(
                params, registry);
        ConnManagerParams.setTimeout(params, 6000);
        httpclient=new DefaultHttpClient(ccm,params);
        return httpclient;
    } catch (Exception e) {
        Log.d(TAG, "Exception creating defaultClient");
        e.printStackTrace();
        return new DefaultHttpClient();
    } 
}

我已经使用了连接超时。我在 AsyncTask 的 doInBackground 方法中执行 http post

@Override      
protected Boolean doInBackground(Object... argList) {       
try {           
HttpResponse response;   

if (this.requestMethod.equals(GET)) {

            HttpGet httpGet = new HttpGet(url);

            response = client.execute(httpGet);

        } else {

            HttpPost httpPost = new HttpPost(url);
            Log.d(TAG, "http post ");
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();

            if (values != null) {
                for (Map.Entry<String, String> entry : values.entrySet()) {
                    nameValuePairs.add(new BasicNameValuePair(entry
                            .getKey(), entry.getValue()));
                }
                httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs, "UTF-8"));
            }

            response = client.execute(httpPost);
            Log.d(TAG, "client execute");
        }

        /* setting a response code. */
        this.responseCode = response.getStatusLine().getStatusCode();

        returnflag = (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK);

        // Get the response
        StringBuilder str = new StringBuilder();
        try{
            if (returnflag) {
                BufferedReader rd = new BufferedReader(new InputStreamReader(
                    response.getEntity().getContent()));
                String line = "";               
                while ((line = rd.readLine()) != null) {
                str.append(line);
                }
                rd.close();
            }
        } finally{
            try{
                if(response.getEntity()!=null)
                    response.getEntity().consumeContent();  // consume the entity content
            } catch(IOException e){
                e.printStackTrace();
            }

        }

        this.responseString = str.toString();

    } catch (UnknownHostException ex) {
        System.out.println(TAG + " UnknownHostException ");
        ex.printStackTrace();
    } catch (IOException e) {
        System.out.println(TAG + " responseCode " + responseCode);
        e.printStackTrace();
        returnflag = false;
    }
    catch (NullPointerException ex){
        ex.printStackTrace();
        returnflag = false;
    }
    catch (IndexOutOfBoundsException ex)
    {   ex.printStackTrace();
        returnflag = false;
    } catch(Exception e){
        e.printStackTrace();
    }
    finally {

    }

    return returnflag;
    }

基于布尔返回标志，我在 postExecute 中处理结果，其中 extendedHandler 是我在活动中实现的接口的一个实例

protected void onPostExecute(Boolean result) {
if(result) {
        iRequester.onRequestSuccess(responseString, requestCode);
        if(extendedHandler != null) extendedHandler.onRequestSuccessExtended(responseString,    requestCode, this.tagData);
    }
    else {
        iRequester.onRequestFailure(responseCode, requestCode);
        if(extendedHandler != null) extendedHandler.onRequestFailureExtended(responseCode, requestCode, this.tagData);
    }

}

在这个实现下，如果连接不好，我应该如何处理或者在一定时间后取消tast。我不确定仅使用 HttpConnectionParams.setSoTimeout 是否可行。在取消任务之前，有什么方法可以知道消息是否已传递到服务器并且它只是在等待响应。 如果需要进一步澄清，请告诉我。

谢谢

Answer 1

为什么不从服务器发回 ACK 以确认文本已成功接收？

JSON格式的确认结果：

{status: "ok")