如何获取json数组的子节点的值 [英] How to get the value of a child node of a json array

问题描述

请我在解析此链接中的数据列表时遇到一些问题(https://gnews.io/api/v3/top-news?&token=dd21eb88599ccb3411eaad9b314cde23) 我能够从 json 数组中获取数据(文章)但是我如何获取数据来自 josn 数组(来源)

please i am having some issues parsing a list of data form the this link(https://gnews.io/api/v3/top-news?&token=dd21eb88599ccb3411eaad9b314cde23) i am able to get the data from the json array(articles) but how can i get the data from the josn array(sources)

    private void getWebApiData() {
        String WebDataUrl = "https://gnews.io/api/v3/top-news?&token=dd21eb88599ccb3411eaad9b314cde23";
        new AsyncHttpTask.execute(WebDataUrl);
    }

    @SuppressLint("StaticFieldLeak")
    public class AsyncHttpTask extends AsyncTask<String, Void, String> {

        @Override
        protected String doInBackground(String... urls) {
            String result = "";

            URL url;
            HttpsURLConnection urlConnection = null;
            try {
                url = new URL(urls[0]);
                urlConnection = (HttpsURLConnection) url.openConnection();
                if (result != null) {
                    String response = streamToString(urlConnection.getInputStream());
                    parseResult(response);
                    return result;
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String result) {
            if (result != null) {
                newsAdapter = new NewsAdapter(getActivity(), newsClassList);
                listView.setAdapter(newsAdapter);
                Toast.makeText(getContext(), "Data Loaded Successfully", Toast.LENGTH_SHORT).show();

            } else {
                Toast.makeText(getContext(), "Failed to load data!", Toast.LENGTH_SHORT).show();
            }
            progressBar.setVisibility(View.GONE);
        }
    }

    private String streamToString(InputStream stream) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(stream));
        String line;
        String result = "";
        while ((line = bufferedReader.readLine()) != null) {
            result += line;
        }

        // Close stream
        if (null != stream) {
            stream.close();
        }
        return result;
    }


    private void parseResult(String result) {
        try {
            JSONObject response = new JSONObject(result);
            JSONObject response2 = response.getJSONObject("articles");
            NewsClass newsClass;
            for (int i = 0; i < newsClass.length(); i++) {
                JSONObject post = newsClass.optJSONObject(i);
                String name = post.optString("name");
                newsClass = new newsClass();
                newsClass.setNews_Name(name);
                artistClassList.add(newsClass);
            }

        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

这是我用来获取文章数据的代码.获取我尝试过的来源

This is code I am using the get the data of the articles. To get the sources I have tried

    private void parseResult(String result) {
        try {
            JSONObject response = new JSONObject(result);
            JSONObject response2 = response.getJSONArray("articles");
            JSONObject response3 = response2.getJSONObject("sources");
            NewsClass newsClass;
            for (int i = 0; i < newsClass.length(); i++) {
                JSONObject post = newsClass.optJSONObject(i);
                String name = post.optString("name");
                newsClass = new newsClass();
                newsClass.setNews_Name(name);
                artistClassList.add(newsClass);
            }

        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

但我想我没有正确获取代码

But I think I am not getting the code correctly

这是我尝试过的第二个选项

Here is the second option I have tried

    private void parseResult(String result) {
        try {
            JSONObject response = new JSONObject(result);

            JSONObject response = response2.getJSONObject("sources");
            NewsClass newsClass;
            for (int i = 0; i < newsClass.length(); i++) {
                JSONObject post = newsClass.optJSONObject(i);
                String name = post.optString("name");
                newsClass = new newsClass();
                newsClass.setNews_Name(name);
                artistClassList.add(newsClass);
            }

        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

但这只会给我空文本字段填充数据的空格但它是空白的请任何帮助将不胜感激

But this only gives me empty text Fields the spaces for the data is populated but it is blank Please any help will be greatly appreciated

推荐答案

我不知道你的代码是如何工作的.您尝试将 JSONObject 作为 articles 获取，实际上是 JSONArray.除此之外，我在您的 json 中没有找到任何 key 像 sources 而是我找到了 source.要解析源，请尝试以下方式:

I don't know how your code works. You have tried to get JSONObject as articles which is actually JSONArray. Besides this I don't find any key in your json like sources instead I have found source. To parse source try below way:

try {
    JSONObject jsonObject = new JSONObject(result);
    JSONArray jsonArray = jsonObject.getJSONArray("articles");

    for(int i = 0; i < jsonArray.length(); i++) {
        JSONObject articleObject = jsonArray.getJSONObject(i);
        JSONObject sourceObject = articleObject.getJSONObject("source");

        String name = sourceObject.optString("name");
        String url = sourceObject.optString("url");
    }
} catch (JSONException e) {
    e.printStackTrace();
}

这篇关于如何获取json数组的子节点的值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！