执行JSON查询时出现AndroidLockGuardPolicy错误

我在尝试执行JSON查询时遇到AndroidLockGuardPolicy错误。看看其他的例子，我想使用AsyncTask，我想我已经这么做了，但是我得到了一个错误。。。我只是没看到什么吗

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.pm_article);
    context = this;

    StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
    .detectAll()
    .penaltyLog()
    .penaltyDialog()
    .build());


    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setHomeButtonEnabled(true);
    // getting product details from intent
     Intent i = getIntent();

        // getting product id -section id (sid) from intent

        //Receive the section id (SID) from th intent
        String id = i.getStringExtra(PM_section.INTENT_ID);
        id_pub = id;
        new GetProductDetails().execute();

}

异步任务

   class GetProductDetails extends AsyncTask<String, String, String> {


        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(PM_article.this);
            pDialog.setMessage("Loading product details. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Getting product details in background thread
         * */

        protected String doInBackground(String... args) {
            runOnUiThread(new Runnable() {
                public void run () {
                    SharedPreferences sharedPrefs = PreferenceManager
                            .getDefaultSharedPreferences(context);
                    int success;
                    try {
                        //sid2.setText("ID: " + id_pub); 
                        // Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("id", id_pub));
                        System.out.println("Loading stories into the activity!");
                        // getting product details by making HTTP request
                        // Note that product details url will use GET request
                        JSONObject json = jParser.makeHttpRequest(url_load_article, "GET", params);
                        System.out.println("Loading stories into the actisadfsafdsafvity!");
                        // check your log for json response
                        Log.d("Single Product Details", json.toString());

                        // json success tag
                        success = json.getInt(TAG_SUCCESS);
                        if (success == 1) {
                            // successfully received product details
                            JSONArray contentObj = json
                                    .getJSONArray(TAG_PRODUCT); // JSON Array

                            // get first product object from JSON Array
                            JSONObject product = contentObj.getJSONObject(0);

                            // product with this pid found
                            // Edit Text
                            art_title = (TextView) findViewById(R.id.display_title);
                            art_author = (TextView) findViewById(R.id.display_author);
                            art_publishtime = (TextView) findViewById(R.id.display_date);
                            art_content = (TextView) findViewById(R.id.display_content);

                            // display product data in TextView
                            int text_size = Integer.parseInt(sharedPrefs.getString("prefFontSize", "1"));

                            art_title.setText(product.getString(TAG_TITLE));
                                art_title.setTextSize(TypedValue.COMPLEX_UNIT_SP, text_size+20);
                            art_author.setText(product.getString(TAG_AUTHOR));
                                art_author.setTextSize(TypedValue.COMPLEX_UNIT_SP, text_size+14);    
                                      art_publishtime.setText(product.getString(TAG_PUBLISHTIME));
                                art_publishtime.setTextSize(TypedValue.COMPLEX_UNIT_SP, text_size+14);
                            art_content.setText(product.getString(TAG_CONTENT));
                                art_content.setTextSize(TypedValue.COMPLEX_UNIT_SP, text_size+18);

                        }else{
                            // product with pid not found
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            });


            return null;
        }
        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once got all details
            pDialog.dismiss();
        }

    }   

---

当前，您正在尝试访问Ui元素并从AsyncTask的

doInBackground

运行

runOnUiThread

，这是不可能的

您需要在

onPreExecute

中移动所有UI元素初始化，并在doInBackground执行完成时使用

onPostExecute

更新UI元素。将您的

AsyncTask

类创建为：

class GetProductDetails extends AsyncTask<String, String, String> {

// Declare UI elemnts here

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
              // show ProgressDialog and initilize Ui elemnts
        }

        protected String doInBackground(String... args) {

             // add your code here from makeing JSON request 
             // 
            return null;
        }
        protected void onPostExecute(String file_url) {
            // Update UI when doInBackground exection completes
        }

    }   

类GetProductDetails扩展异步任务{
//在此声明UI元素
@凌驾
受保护的void onPreExecute（）{
super.onPreExecute（）；
//显示ProgressDialog并初始化Ui元素
}
受保护的字符串doInBackground（字符串…args）{
//通过生成JSON请求在此处添加代码
// 
返回null；
}
受保护的void onPostExecute（字符串文件\u url）{
//doInBackground执行完成时更新UI
}
}   

有关如何在应用程序中使用AsyncTask的更多信息，请参阅：

---

我将错误日志张贴在主帖子上。它太长了，无法放在评论中。你应该用ρцσѕρєK的答案。您无法从后台线程更新UI。因此，在受保护的字符串doInBackground（String…args）{}中，我删除了runOnUiThread（new Runnable（）？哇，对不起。非常感谢您的帮助！

class GetProductDetails extends AsyncTask<String, String, String> {

// Declare UI elemnts here

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
              // show ProgressDialog and initilize Ui elemnts
        }

        protected String doInBackground(String... args) {

             // add your code here from makeing JSON request 
             // 
            return null;
        }
        protected void onPostExecute(String file_url) {
            // Update UI when doInBackground exection completes
        }

    }