我目前正在使用已从那里下载并解析的 xml。我想直接从 url 本身做。我怎样才能做到这一点？
我在下面添加了我正在使用的代码段。请帮助提供一个片段或示例。谢谢。
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
File file = new File(this.getFilesDir(), FILE_EXTRACTED);
Document dom = builder.parse(file);
Element root = dom.getDocumentElement();
root.normalize();
使用以下代码从 android 中的 url 解析 xml
public class XMLParsingDOMExample extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
/** Create a new layout to display the view */
LinearLayout layout = new LinearLayout(this);
layout.setOrientation(1);
/** Create a new textview array to display the results */
TextView name[];
TextView website[];
TextView category[];
try {
URL url = new URL("http://www.androidpeople.com/wp-content/uploads/2010/06/example.xml");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(url.openStream()));
doc.getDocumentElement().normalize();
NodeList nodeList = doc.getElementsByTagName("item");
/** Assign textview array lenght by arraylist size */
name = new TextView[nodeList.getLength()];
website = new TextView[nodeList.getLength()];
category = new TextView[nodeList.getLength()];
for (int i = 0; i < nodeList.getLength(); i++) {
Node node = nodeList.item(i);
name[i] = new TextView(this);
website[i] = new TextView(this);
category[i] = new TextView(this);
Element fstElmnt = (Element) node;
NodeList nameList = fstElmnt.getElementsByTagName("name");
Element nameElement = (Element) nameList.item(0);
nameList = nameElement.getChildNodes();
name[i].setText("Name = " + ((Node) nameList.item(0)).getNodeValue());
NodeList websiteList = fstElmnt.getElementsByTagName("website");
Element websiteElement = (Element) websiteList.item(0);
websiteList = websiteElement.getChildNodes();
website[i].setText("Website = " + ((Node) websiteList.item(0)).getNodeValue());
category[i].setText("Website Category = " + websiteElement.getAttribute("category"));
layout.addView(name[i]);
layout.addView(website[i]);
layout.addView(category[i]);
}
} catch (Exception e) {
System.out.println("XML Pasing Excpetion = " + e);
}
/** Set the layout view to display */
setContentView(layout);
}
}
我的解决方案使用已接受答案中的代码，但是我发现如果不使用 AsyncTask 它将无法工作
这是我的代码，首先我检索 XML 并在使用 AsyncTask 的方法中解析它
public class RetrieveFeed extends AsyncTask {
URL url;
ArrayList<String> headlines = new ArrayList();
ArrayList<String> links = new ArrayList();
@Override
protected Object doInBackground(Object[] objects) {
// Initializing instance variables
try {
url = new URL("http://feeds.bbci.co.uk/news/rss.xml?edition=uk");
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xpp = factory.newPullParser();
// We will get the XML from an input stream
xpp.setInput(getInputStream(url), "UTF_8");
/* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
* However, we should take in consideration that the rss feed name also is enclosed in a "<title>" tag.
* As we know, every feed begins with these lines: "<channel><title>Feed_Name</title>...."
* so we should skip the "<title>" tag which is a child of "<channel>" tag,
* and take in consideration only "<title>" tag which is a child of "<item>"
*
* In order to achieve this, we will make use of a boolean variable.
*/
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, etc..
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_TAG) {
if (xpp.getName().equalsIgnoreCase("item")) {
insideItem = true;
} else if (xpp.getName().equalsIgnoreCase("title")) {
if (insideItem)
headlines.add(xpp.nextText()); //extract the headline
} else if (xpp.getName().equalsIgnoreCase("link")) {
if (insideItem)
links.add(xpp.nextText()); //extract the link of article
}
} else if (eventType == XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")) {
insideItem = false;
}
eventType = xpp.next(); //move to next element
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return headlines;
}
public InputStream getInputStream(URL url) {
try {
return url.openConnection().getInputStream();
} catch (IOException e) {
return null;
}
}
public ArrayList<String> heads()
{
return headlines;
}
}
然后在主要活动中：
public class MainActivity extends ListActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ArrayList<String> headlines = new ArrayList<>();
RetrieveFeed getXML = new RetrieveFeed();
getXML.execute();
headlines = getXML.heads();
// Binding data
ArrayAdapter adapter = new ArrayAdapter(this,
android.R.layout.simple_list_item_1, headlines);
setListAdapter(adapter);
}
}
确保您在清单中具有正确的使用权限，将其放在应用程序标签内但在任何活动标签之外
<uses-permission android:name="android.permission.INTERNET"/>
最后，在扩展 ListActivity 时，您需要确保在主布局 xml 中有一个 ListView，其 id 为：
android:id="@android:id/list"
使用此代码。
public class XMLResourceDemo extends ListActivity {
private final static String TAG = XMLResourceDemo.class.getSimpleName();
TextView selection;
ArrayList<String> items = new ArrayList<String>();
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
selection = (TextView) findViewById(R.id.selection);
try {
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(true);
XmlPullParser xpp = factory.newPullParser();
xpp.setInput(new InputStreamReader(
getUrlData("url")));
while (xpp.getEventType() != XmlPullParser.END_DOCUMENT) {
Log.i(TAG, "doc started");
if (xpp.getEventType() == XmlPullParser.START_TAG) {
if (xpp.getName().equals("entry")) {
items.add(xpp.getAttributeValue(0));
}
}
xpp.next();
}
} catch (Throwable t) {
Toast.makeText(this, "Request failed: " + t.toString(),
Toast.LENGTH_LONG).show();
}
setListAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, items));
}
public InputStream getUrlData(String url) throws URISyntaxException, ClientProtocolException, IOException {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet method = new HttpGet(new URI(url));
HttpResponse res = client.execute(method);
return res.getEntity().getContent();
}