Android：在活动之间保持远程服务器上的会话活动

我有另一个内置iOS的应用程序，当用户登录到该应用程序时，服务器会将他们登录到该会话中。在iOS应用程序中，会话与正常会话一样保持活动状态，并且来自应用程序的所有请求都可以看到仍然登录的用户

我认为这与Android应用程序相同，但在登录后，我切换到下一个活动，然后向服务器发送请求以填充页面。我得到的结果是用户没有登录

这里是否有一个我不理解的区别，那就是不能使我在服务器上的会话保持活动状态

我有一个所有活动都扩展的基类，在基类中我有一个受保护的类。我用它来发送所有的请求

protected class API extends AsyncTask <Void, Void, String>
{
    public String RequestName;
    public String RequestType;
    public String RequestUrl;
    public List<NameValuePair> RequestParameters;

    public API(String Name, String Type, String Url, List<NameValuePair> params)
    {
        RequestName = Name;
        RequestType = Type;
        RequestUrl = Url;
        RequestParameters = params;
    }

    protected String getASCIIContentFromEntity(HttpEntity entity) throws IllegalStateException, IOException 
    {
        InputStream in = entity.getContent();
        StringBuffer out = new StringBuffer();
        int n = 1;
        while (n>0) 
        {
            byte[] b = new byte[4096];
            n =  in.read(b);
            if (n>0) 
                out.append(new String(b, 0, n));
        }
        return out.toString();
    }

    @Override
    protected String doInBackground(Void... params) 
    {


        HttpClient httpClient = new DefaultHttpClient();
        HttpContext localContext = new BasicHttpContext();

        String text = null;

        if(RequestType == "post")
        {
            HttpPost p = new HttpPost("http://www.ehrx.com/api/" + RequestUrl);

            try 
            {
                p.setEntity(new UrlEncodedFormEntity(RequestParameters));
                HttpResponse response = httpClient.execute(p, localContext);
                HttpEntity entity = response.getEntity();
                text = getASCIIContentFromEntity(entity);
            } 
            catch (Exception e) 
            {
                return e.getLocalizedMessage();
            }
        }
        else
        {
            HttpGet httpGet = new HttpGet("http://www.ehrx.com/api/" + RequestUrl);

            try 
            {
                HttpResponse response = httpClient.execute(httpGet, localContext);
                HttpEntity entity = response.getEntity();
                text = getASCIIContentFromEntity(entity);
            } 
            catch (Exception e) 
            {
                return e.getLocalizedMessage();
            }
        }



        return text;
    }

    protected void onPostExecute(String results) 
    {
        HandleResult(results, RequestName);

    }
}

---

我猜会话在服务器上仍然是活动的，但是您在android应用程序中丢失了会话cookie。看起来您正在为每个请求创建一个新的客户端和一个新的上下文。您需要为上下文设置cookie存储，以便它可以使用您之前已验证的请求中的会话cookie。的答案应该会给您提供更多信息。

我猜会话在服务器上仍然有效，但您在android应用程序中丢失了会话cookie。看起来您正在为每个请求创建一个新的客户端和一个新的上下文。您需要为上下文设置cookie存储，以便它可以使用您之前已验证的请求中的会话cookie。的答案应该会给您提供更多信息。

使用单例类可以轻松解决此问题。您应该在所有HTTP请求中使用相同的HTTP客户端。

使用单例类可以轻松解决此问题。您应该在所有HTTP请求中使用相同的HTTP客户端

protected class API extends AsyncTask <Void, Void, String>
{
    public String RequestName;
    public String RequestType;
    public String RequestUrl;
    public List<NameValuePair> RequestParameters;

    public API(String Name, String Type, String Url, List<NameValuePair> params)
    {
        RequestName = Name;
        RequestType = Type;
        RequestUrl = Url;
        RequestParameters = params;
    }

    protected String getASCIIContentFromEntity(HttpEntity entity) throws IllegalStateException, IOException 
    {
        InputStream in = entity.getContent();
        StringBuffer out = new StringBuffer();
        int n = 1;
        while (n>0) 
        {
            byte[] b = new byte[4096];
            n =  in.read(b);
            if (n>0) 
                out.append(new String(b, 0, n));
        }
        return out.toString();
    }

    @Override
    protected String doInBackground(Void... params) 
    {


        HttpClient httpClient = new DefaultHttpClient();
        HttpContext localContext = new BasicHttpContext();

        String text = null;

        if(RequestType == "post")
        {
            HttpPost p = new HttpPost("http://www.ehrx.com/api/" + RequestUrl);

            try 
            {
                p.setEntity(new UrlEncodedFormEntity(RequestParameters));
                HttpResponse response = httpClient.execute(p, localContext);
                HttpEntity entity = response.getEntity();
                text = getASCIIContentFromEntity(entity);
            } 
            catch (Exception e) 
            {
                return e.getLocalizedMessage();
            }
        }
        else
        {
            HttpGet httpGet = new HttpGet("http://www.ehrx.com/api/" + RequestUrl);

            try 
            {
                HttpResponse response = httpClient.execute(httpGet, localContext);
                HttpEntity entity = response.getEntity();
                text = getASCIIContentFromEntity(entity);
            } 
            catch (Exception e) 
            {
                return e.getLocalizedMessage();
            }
        }



        return text;
    }

    protected void onPostExecute(String results) 
    {
        HandleResult(results, RequestName);

    }
}