连接webservice时出错

Question

我在main.java

中编写了这段代码

ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
        try{
             HttpClient httpclient = new DefaultHttpClient();
             HttpPost httppost = new HttpPost("http://way2tutorial.com/json/index.php");
             httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
             HttpResponse response = httpclient.execute(httppost);
             HttpEntity entity = response.getEntity();
             InputStream is = entity.getContent();
             }catch(Exception e){
                 Log.e("log_tag", "Error in http connection"+e.toString());
            }

还包括

<uses-permission android:name="android.permission.INTERNET"/>

清单文件中的

但在http

中运行android应用程序错误时出错

  

connectionandroid.os.NetworkOnMainThreadException

Answer 1

您无法通过应用程序主线程上的网络执行任何操作。您必须在新线程中运行它，我建议在AsyncTask中执行它。在这里查看示例 - http://developer.android.com/reference/android/os/AsyncTask.html

Answer 2

此错误，因为您正在事件线程中执行网络任务。新的Sdk版本迫使开发人员将网络任务执行到除事件线程之外的其他线程。要解决此问题，请为此创建一个单独的线程，

Handler和AsyncTask是在EventThread以外的其他线程中处理这些类型任务的方法，

请参阅以下链接以了解事件线程和网络任务实现：

http://developer.android.com/reference/android/os/AsyncTask.html

http://www.vogella.de/articles/AndroidPerformance/article.html

Answer 3

从Honeycomb（v 3.0）开始，不允许在主线程上执行网络任务。尝试在AsyncTask上执行此操作，或者如果您确实在执行一些简单的任务，请尝试将清单中的minsdkversion更改为低于11。

http://developer.android.com/reference/android/os/NetworkOnMainThreadException.html

Answer 4

从Honeycomb开始，即3.0 you are no longer allowed to do network operations in application's main thread。您应该创建一个单独的线程来执行网络操作。请尝试使用以下代码：

ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
new Thread()
{
    public void run()
    {
        try
        {
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost("http://way2tutorial.com/json/index.php");
            httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            InputStream is = entity.getContent();
        }
        catch(Exception e)
        {
            Log.e("log_tag", "Error in http connection"+e.toString());
        }
    }
}.start();