Question

我有一个使用AsyncTask的应用程序，每当我决定在它仍在运行时关闭它时，结束时会有轻微的延迟。有什么办法可以解决吗？

这是我的代码：

private class GetAPI extends AsyncTask<String, Void, ArrayList<Question>> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        Log.i("QA", "Begin GETAPI");
    }

    @Override
    protected ArrayList<Question> doInBackground(String... urls) {
        InputStream inputStream;
        try {

            // create HttpClient
            HttpClient httpclient = new DefaultHttpClient();

            // make GET request to the given URL
            HttpResponse httpResponse = httpclient.execute(new HttpGet(urls[0]));

            // receive response as inputStream
            inputStream = httpResponse.getEntity().getContent();

            questions = new ArrayList<>();

            // convert inputstream to string
            if (inputStream != null) {
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
                String line;
                while ((line = reader.readLine()) != null) {
                    JSONArray ja = new JSONArray(line);

                    for (int i = 0; i < ja.length(); i++) {
                        JSONObject jo = (JSONObject) ja.get(i);
                        Log.i("QA", "Retrieved question " + i);
                        questions.add(new Question(jo.getString("questionText"), jo.getInt
                                ("magnetid"), "", jo.getInt("personid"), jo.getInt("id")));
                        questions.get(i).setId(jo.getInt("id"));
                    }
                }
            } else
                throw new InputMismatchException("Didn't work");
        } catch (JSONException | IOException e) {
            e.printStackTrace();
        }

        return questions;
    }

    // onPostExecute displays the results of the AsyncTask.
    @Override
    protected void onPostExecute(ArrayList<Question> strings) {
        super.onPostExecute(strings);
        Log.i("QA", "End GETAPI");
        QuestionAdapter questionAdapter = new QuestionAdapter(questions);
        recyclerView.setAdapter(questionAdapter);
        refreshContent(false);
    }
}

我不太明白为什么在最近的应用程序屏幕中运行AsyncTask并关闭此应用程序时，它会导致手机延迟。是因为我没有覆盖onCancel()方法吗？

Answer 1

您可以（并且应该）使用提供的方法关闭AsyncTask。您可以将取消调用绑定到Activity的特定生命周期方法。

How to stop asynctask thread in android?

在AsyncTask期间关闭应用程序

1 个答案: