Question

我已经阅读了很多教学内容，并且努力尝试但不知何故，仍然无法让我的InputStream正常工作。所以我转向你。预先感谢您的帮助！

我的目标是从空白HTML网页获取数据并将其显示在我的Android应用中的TextView上。我在清单中包含了所有互联网权限，而我的XML文件只是线性布局中的文本视图。该应用程序只有一个名为＆＃34; scorereader＆＃34;那是关于它的。当我运行它时，它只显示带有textview的空白XML。它不显示来自HttpClient的文本。

JAVA：scorereader.java

public class scorereader extends Activity {

    public void onCreate(Bundle savedInstanceState) {
    try
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mainactivity); 

        TextView tv = (TextView)findViewById(R.id.resultbox);
        try{
            HttpClient httpclient = new DefaultHttpClient(); 
            HttpPost httppost = new HttpPost("http://greentapcore.tumblr.com/");
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            InputStream webs = entity.getContent();
            try{

                BufferedReader reader = new BufferedReader(new InputStreamReader(webs,"iso-8859-1"),8);
                tv.setText(reader.readLine()); 
                webs.close();

            }catch(Exception e){
                Log.e("log_tag", "Error converting result "+e.toString()); 
            }
        }catch(Exception e){
            Log.e("log_tag", "Error in HTTP connection "+e.toString());

        }

    }
    catch (Exception e)
    { 
        Log.e("ERROR", "ERROR IN CODE: " + e.toString()); 
        e.printStackTrace();

    }

} 

}

来自Tumblr网站的HTML： - 带有＆＃34; hi＆＃34;的完整空白页面在顶部。

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>scoretrack</title>
    <link rel="stylesheet" href="style.css">
    <script src="script.js"></script>
  </head>
  <body>
    hi
  </body>
</html>

提前非常感谢！非常感谢。

Answer 1

使用HttpGet代替HttpPost。 HttpGet将执行GET请求而不是POST请求，这应该正确下载网页。

Answer 2

注意日志中的消息

Error in HTTP connection android.os.NetworkOnMainThreadException

在另一个线程中跟随对服务器的请求

private TextView tv;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mainactivity);
        tv = (TextView)findViewById(R.id.resultbox);
        new Task().execute();

    }

    class Task extends AsyncTask<Void, Void, String>{
        @Override
        protected String doInBackground(Void... params) {
            try{
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost("http://greentapcore.tumblr.com/");
                HttpResponse response = httpclient.execute(httppost);
                HttpEntity entity = response.getEntity();
                InputStream webs = entity.getContent();
                try{
                    StringBuilder result = new StringBuilder();
                    BufferedReader reader = new BufferedReader(new InputStreamReader(webs,"iso-8859-1"),8);
                    String line;
                    while( (line = reader.readLine()) != null) {
                        result.append(line);
                    }
                    webs.close();
                    return result.toString();

                }catch(Exception e){
                    Log.e("log_tag", "Error converting result "+e.toString());
                }
            }catch(Exception e){
                Log.e("log_tag", "Error in HTTP connection "+e.toString());

            }
            return null;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            if(s != null){
                tv.setText(s);
            }
        }
    }

使用InputStream从WebPage获取数据？

2 个答案: