java - Android Studio，java公共(public)类中的线程

Question

我创建了一个学生类，它调用一个需要用学生填充链接列表的线程。

class Students{
private LinkedList<Student> students = new LinkedList<Student>();
android.os.Handler handler = new android.os.Handler();

public String Fill() throws MalformedURLException {

    String msg = "++";
    new Thread(){
        public void run(){
                HttpURLConnection htcon=null;
                try {
           URL my_url = new URL("http://www.whatever.net/fill.php");
          htcon = (HttpURLConnection) my_url.openConnection();          
            htcon.setDoOutput(true);
            htcon.setUseCaches(false);

                    htcon.connect();                
            int responseCode = htcon.getResponseCode();
            if(responseCode ==HttpURLConnection.HTTP_OK){
                InputStream stream = htcon.getInputStream();
            BufferedReader bfr = new BufferedReader(new InputStreamReader(stream,"UTF-8"));
            String line = "";
           StringBuilder strbld = new StringBuilder();
            while ((line = bfr.readLine()) != null) {
                strbld.append(line);
            }
                if (bfr!=null)
                {
                bfr.close();
                }
            String[] ary = strbld.toString().split("\n");
            for (int i = 0; i < ary.length; i++) {
      final Student temp = new Student(ary[i].toString().split(":")[0], "1210",Integer.parseInt(ary[i].toString().split(":")[1]), 0);

                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        students.push(new Student("jjj","k",9,9));
                    }
                });
              }//for
                if (htcon!=null)
                htcon.disconnect();
            }

        } catch (MalformedURLException e) {
            e.printStackTrace();               
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                }
            }
         }

    }.start();
     return toBinaryString(students.size());
}

问题是，当处理程序运行时，它不会更改列表。大小仍然是 0

这是我的 UI 类的样子(主要 Activity )

TextView txtv = (TextView) findViewById(R.id.textv);
        Students students1 = new Students();
        try {
            msg = students1.Fill();
        } catch (MalformedURLException e) {
            e.printStackTrace();
            Toast.makeText(this, e.toString(), Toast.LENGTH_LONG);
        }

Answer 1

您的线程正在异步运行。所以，它会立即执行:

return toBinaryString(students.size());

当线程仍在进行中时。 AsyncTask确实足以解决你的问题。希望对您有所帮助。