从 Android 发送 JSON

Question

我尝试使用以下代码将 JSON 对象从我的 android 应用程序发送到 Django。但是有一些错误，我的应用程序退出时说不幸停止了。

代码：

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
EditText uname, upass;
Button submit;
String name,pass;
public static final String wurl = "http://172.21.1.59:8000/polls/";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);

    uname=(EditText)findViewById(R.id.editusername);
    upass=(EditText)findViewById(R.id.editpwd);
    submit=(Button)findViewById(R.id.btnSubmit);

    submit.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            name=uname.getText().toString();
            pass=upass.getText().toString(); 
            JSONObject obj = new JSONObject();
            try 
            {
                obj.put("Name", name);
                obj.put("Password", pass);
            } catch (JSONException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }

            HttpParams myParams = new BasicHttpParams();
            HttpConnectionParams.setConnectionTimeout(myParams, 10000);
            HttpConnectionParams.setSoTimeout(myParams, 10000);
            HttpClient httpclient = new DefaultHttpClient(myParams );


            try {

                HttpPost httppost = new HttpPost(wurl.toString());
                httppost.setHeader("Content-type", "application/json");

                StringEntity se = new StringEntity(obj.toString()); 
                se.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
                httppost.setEntity(se); 

                HttpResponse response = httpclient.execute(httppost);
                String temp = EntityUtils.toString(response.getEntity());
                Log.i("tag", temp);


            } catch (ClientProtocolException e) {

            } catch (IOException e) {
            }
            catch (Exception e) {
                Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
            }

        }
    });


    if (savedInstanceState == null) {
        getFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment())
                .commit();
    }
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {

    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.login, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

/**
 * A placeholder fragment containing a simple view.
 */
public static class PlaceholderFragment extends Fragment {

    public PlaceholderFragment() {
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_login, container, false);
        return rootView;
    }
} 

}

应用程序在运行“HttpResponse response = httpclient.execute(httppost);”行时退出。

请有人帮我解决这个问题。谢谢。

Answer 1

在 Android 中，您不能在主线程上运行网络任务。您应该改用 AsyncTask。

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