MainActivity.DownloadWebpageTask不是抽象的，不覆盖AsyncTask的抽象方法doInBackground（字符串...）

问题描述

 公共类MainActivity延伸活动{    TextView的电视;    @覆盖
    保护无效的onCreate（捆绑savedInstanceState）{
        super.onCreate（savedInstanceState）;
        的setContentView（R.layout.activity_main）;        电视=（的TextView）findViewById（R.id.data）;        串的serviceUrl = - ; //我不能表现出来
        串的serviceKey = - ; //我不能表现出来
        的serviceKey = URLEn coder.en code（的serviceKey）;
        字符串strSrch =406;
        字符串strUrl =的serviceUrl + + +的serviceKey与＆amp; strSrch =的serviceKey =？+ strSrch;        新DownloadWebpageTask（）执行（strUrl）;
    }    私有类DownloadWebpageTask扩展的AsyncTask＆LT;弦乐，太虚，字符串＆GT; {        @覆盖
        保护字符串doInBackgroud（字符串的URL ...）{
            尝试{
                返回（字符串）downloadUrl（（字符串）网址[0]）;
            }赶上（IOException异常五）{
                返回下载失败;
            }
        }        保护无效onPostExecute（字符串结果）{
            tv.append（结果+\\ n）;
            tv.append（=======解析结果========= \\ n）;            尝试{
                XmlPullParserFactory工厂= XmlPullParserFactory.newInstance（）;
                factory.setNamespaceAware（真）;
                XmlPullParser XPP = factory.newPullParser（）;                xpp.setInput（新StringReader（结果））;
                INT EVENTTYPE = xpp.getEventType（）;
                布尔BSET = FALSE;
                而（EVENTTYPE！= XmlPullParser.END_DOCUMENT）{
                    如果（EVENTTYPE == XmlPullParser.START_DOCUMENT）{
                        ;
                    }否则如果（EVENTTYPE == XmlPullParser.START_TAG）{
                        字符串TAG_NAME = xpp.getName（）;
                        如果（tag_name.equals（busRouteNm）|| tag_name.equals（busRouteId））
                            BSET =真;
                    }否则如果（EVENTTYPE == XmlPullParser.TEXT）{
                        如果（BSET）{
                            字符串内容= xpp.getText（）;
                            tv.append（内容+\\ n）;
                            BSET = FALSE;
                        }
                    }否则如果（EVENTTYPE == XmlPullParser.END_TAG）{
                        ;
                    }
                    EVENTTYPE = xpp.next（）;
                }
            }赶上（例外五）{
                tv.setText（e.getMessage（））;
            }
        }        私人字符串downloadUrl（字符串myurl）抛出IOException            HttpURLConnection的康恩= NULL;
            尝试{
                网址URL =新的URL（myurl）;
                康恩=（HttpURLConnection类）url.openConnection（）;
                BUF的BufferedInputStream =新的BufferedInputStream（conn.getInputStream（））;
                的BufferedReader bufreader =新的BufferedReader（新的InputStreamReader（BUF，UTF-8））;
                串线= NULL;
                字符串页=;
                而（（行= bufreader.readLine（））！= NULL）{
                    网页+ =行;
                }
                返回页面;
            } {最后
                conn.disconnect（）;
            }
        }
    }}
 

私有类DownloadWebpageTask扩展的AsyncTask
此行有错误：

解决方案

Typo in method name. Change

protected String doInBackgroud

to

protected String doInBackground

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