来自URL的XML解析在Android

Question

我想从XML Parsing实施url。下面是使用xml解析的代码，但它不起作用。任何人都可以帮助我相应地获得response。

    public class MainActivity extends AppCompatActivity {

    // Declare variables
    TextView textview;
    NodeList nodelist;
    ProgressDialog pDialog;

    // Insert image URL
//    String URL = "http://www.androidbegin.com/tutorial/XMLParseTutorial.xml";
    String URL = "my private url";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        new DownloadXML().execute(URL);

        textview = (TextView) findViewById(R.id.text);
    }


    // DownloadXML AsyncTask
    private class DownloadXML extends AsyncTask<String, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            // Create a progressbar
            pDialog = new ProgressDialog(MainActivity.this);
            // Set progressbar title
            pDialog.setTitle("Android Simple XML Parsing using DOM Tutorial");
            // Set progressbar message
            pDialog.setMessage("Loading...");
            pDialog.setIndeterminate(false);
            // Show progressbar
            pDialog.show();
        }

        @Override
        protected Void doInBackground(String... Url) {
            try {
                URL url = new URL(Url[0]);
                DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

                DocumentBuilder db = dbf.newDocumentBuilder();
                // Download the XML file
                Document doc = db.parse(new InputSource(url.openStream()));
                doc.getDocumentElement().normalize();

                Log.e("testing "," ==>");


                // Locate the Tag Name
//                nodelist = doc.getElementsByTagName("item");
                nodelist = doc.getElementsByTagName("ApiResponseOfTwiliosZ_PlQ1mzg");

            } catch (Exception e) {
                Log.e("Error", e.getMessage());
                e.printStackTrace();
            }
            return null;

        }

        @Override
        protected void onPostExecute(Void args) {

            for (int temp = 0; temp < nodelist.getLength(); temp++) {
                Node nNode = nodelist.item(temp);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                    Element eElement = (Element) nNode;
                    // Set the texts into TextViews from item nodes
                    // Get the title


                    Log.e("Message checking "," ===> "+getNode("ResponseStatus", eElement));



                }
            }
            // Close progressbar
            pDialog.dismiss();
        }
    }

    // getNode function
    private static String getNode(String sTag, Element eElement) {
        NodeList nlList = eElement.getElementsByTagName(sTag).item(0)
                .getChildNodes();
        Node nValue = (Node) nlList.item(0);
        return nValue.getNodeValue();
    }
}

并且错误如下所示。

java.lang.NullPointerException: Attempt to invoke interface method 'int org.w3c.dom.NodeList.getLength()' on a null object reference

我希望从此回复中获得token。

以下是我的api response

    <ApiResponseOfTwiliosZ_PlQ1mzg xmlns:i="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns="http://schemas.datacontract.org/2004/07/Healthcare4Free.WebApi.Models">
<Data i:nil="true"/>
<ResponseStatus>
<Message>Success</Message>
<StatusCode>200</StatusCode>
<TwilioToken>
<Token>
eyJjdHkiOiJ0d2lsaW8tZnBhO3Y9MSIsInR5cCI6IkpXVCIsImFsZyI6IkhTMjU2In0.eyJpc3MiOiJTSzMxZDVjM2NiNDVmMjQ2ZjI5NDY4MTFlOGQxYWZlYjM4IiwiZXhwIjoxNTA4Njc4NzYzLCJqdGkiOiJTSzMxZDVjM2NiNDVmMjQ2ZjI5NDY4MTFlOGQxYWZlYjM4LTE1MDg2NzUxNjMiLCJzdWIiOiJBQzdlNDBhZjY1YTYwMGYyYmQ3Yjg2Zjk1OTFkZjM4ZTFiIiwiZ3JhbnRzIjp7ImlkZW50aXR5IjoiaWRlbnRpdHkiLCJ2aWRlbyI6eyJyb29tIjoicm9vbUlkIn19fQ.yHKcOOiUrVZKYsQ3110YzgprRpODd9fp1dQLQFNw7Gw
</Token>
</TwilioToken>
</ResponseStatus>
</ApiResponseOfTwiliosZ_PlQ1mzg>

Answer 1

要让令牌更新您的代码：

在doInBackground（）

中

Log.e("Message checking ", " ===> " + getNode("Token", eElement));

在你的onPostExecute（）

中

TextView textview;

    NodeList nodelist;
    ProgressDialog pDialog;
    String URL = "http://json-gen.com/rest/service/get/uCSFzJgDKrjq7DKCNiQtm";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        new DownloadXML().execute(URL);

        textview = (TextView) findViewById(R.id.text);
    }


    // DownloadXML AsyncTask
    private class DownloadXML extends AsyncTask<String, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            // Create a progressbar
            pDialog = new ProgressDialog(MainActivity.this);
            // Set progressbar title
            pDialog.setTitle("Android Simple XML Parsing using DOM Tutorial");
            // Set progressbar message
            pDialog.setMessage("Loading...");
            pDialog.setIndeterminate(false);
            // Show progressbar
            pDialog.show();
        }

        @Override
        protected Void doInBackground(String... Url) {
            try {
                URL url = new URL(Url[0]);
                DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

                DocumentBuilder db = dbf.newDocumentBuilder();
                // Download the XML file
                Document doc = db.parse(new InputSource(url.openStream()));
                doc.getDocumentElement().normalize();

                Log.e("testing ", " ==>");


                // Locate the Tag Name
//                nodelist = doc.getElementsByTagName("item");
                nodelist = doc.getElementsByTagName("TwilioToken");

            } catch (Exception e) {
                Log.e("Error", e.getMessage());
                e.printStackTrace();
            }
            return null;

        }

        @Override
        protected void onPostExecute(Void args) {

            Node nNode = nodelist.item(0);
            if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                Element eElement = (Element) nNode;
                // Set the texts into TextViews from item nodes
                // Get the title


                Log.e("Message checking ", " ===> " + getNode("Token", eElement));
                textview.setText(getNode("Token", eElement));

            }
            // Close progressbar
            pDialog.dismiss();
        }
    }

    // getNode function
    private static String getNode(String sTag, Element eElement) {
        NodeList nlList = eElement.getElementsByTagName(sTag).item(0)
                .getChildNodes();
        Node nValue = (Node) nlList.item(0);
        return nValue.getNodeValue();
    }

以下是完整的代码：

library(relsurv)
library(survminer)

fit.hist <- rs.surv(Surv(time,cens)~ordered(Hist)+
ratetable(age = age, sex = sex, year = year), 
ratetable = poptab, method="pohar-perme")