Android using HttpClient method and error-prone problem

HttpClient provides Android developers with a simple way to operate HTTP network connections, there are two ways to connect, get and post, first look at how to implement the

The default is Get mode

//first put parameters into list  , and then URL-encode the parameter list<basicnamevaluepair> params = new linkedlist<basicnamevaluepair> ();  Params.add (New Basicnamevaluepair ("param1", "China"));  Params.add (New Basicnamevaluepair ("param2", "value2"));    BASEURL String baseUrl = "http://www.baidu.com";                Stitching the URL and parameters httpget GetMethod = new HttpGet (BaseUrl + "?" + param);    HttpClient HttpClient = new Defaulthttpclient (); try {httpresponse response = Httpclient.execute (GetMethod);//Initiate GET request LOG.I (TAG, "Rescode =" + response.gets Tatusline (). Getstatuscode ()); Get the response code LOG.I (TAG, "result =" + entityutils.tostring (response.getentity (), "Utf-8"));//Get server response content} catch (Clientpro  Tocolexception e) {//TODO auto-generated catch block E.printstacktrace ();  } catch (IOException e) {//TODO auto-generated catch block E.printstacktrace (); }  

Post mode

In the same way as GET, the parameter is first placed in the list params = new linkedlist<basicnamevaluepair> ();  Params.add (New Basicnamevaluepair ("param1", "POST Method"));                Params.add (New Basicnamevaluepair ("Param2", "second parameter"));      try {httppost Postmethod = new HttpPost (BASEURL); Postmethod.setentity (New urlencodedformentity (params, "utf-8")); Fill in the parameters into post entity httpresponse response = Httpclient.execute (Postmethod); Execute the Post method log.i (TAG, "Rescode =" + Response.getstatusline (). Getstatuscode ()); Get the response code LOG.I (TAG, "result =" + entityutils.tostring (response.getentity (), "Utf-8")); Get response content} catch (Unsupportedencodingexception e) {//TODO auto-generated catch block E.prin  Tstacktrace ();  } catch (Clientprotocolexception e) {//TODO auto-generated catch block E.printstacktrace ();  } catch (IOException e) {//TODO auto-generated catch block E.printstacktrace (); }

If you need to update the UI after you get the network resources, you need to use async, otherwise an error will occur

Handler Handler = new Handler () {@Override public void Handlemessage (Message msg) {if (msg.what            = = 0x123) {tv.settext (result);    }        }    };        @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);        Setcontentview (R.layout.activity_main);        TV = (TextView) Findviewbyid (r.id.tv);        result = "";        Final HttpClient HttpClient = new Defaulthttpclient (); New Thread () {public void run () {HttpGet HttpRequest = new HttpGet ("HT                Tp://www.baidu.com ");                    try {HttpResponse HttpResponse = Httpclient.execute (HttpRequest);                        if (Httpresponse.getstatusline (). Getstatuscode () = = HTTPSTATUS.SC_OK) {//Get the returned string                                              result = Entityutils.tostring (httpresponse.getentity ()); Tv.settext(result);//If you use it here you will get an error message msg = new Message ();                       Msg.what = 0x123;                    Handler.sendmessage (msg);                    }} catch (Clientprotocolexception e) {//TODO auto-generated catch block                E.printstacktrace ();                } catch (IOException e) {//TODO auto-generated catch block E.printstacktrace ();        }}}.start (); }