问题
I have to fetch the data from xml feed and display on android application.
my xml feed is looking like:
<root>
<Categories>
<Category name="Books">
<Articles>
<article articleid="4537" title="Android" />
<article articleid="4560" title="Java" />
<article articleid="4585" title="PHP" />
<article articleid="4731" title="MySql" />
</Articles>
</Category>
<Category name="Names">
<Articles>
<article articleid="266" title="Dita" />
<article articleid="268" title="Frieda" />
<article articleid="269" title="Demi" />
<article articleid="271" title="Shyamalan" />
<article articleid="269" title="Krish" /></Articles>
</Category>
</Categories></root>
Here i have to display category name.also have to display the article title for belonging category.i wish to display the output is:
Books
Android Java PHP MySql
Names
Dita Frieda Demi Shyamalan Krish
I have using below code:
static final String KEY_TITLE = "Category";
static final String KEY_ARTICLE = "article";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();
XMLParser parser = new XMLParser();
String xml = parser.getXmlFromUrl(URL); // getting XML from URL
Document doc = parser.getDomElement(xml); // getting DOM element
NodeList nl = doc.getElementsByTagName(KEY_TITLE);
NodeList nl1 = doc.getElementsByTagName(KEY_ARTICLE);
System.out.println(nl.getLength());
// looping through all song nodes <song>
for (int i = 0; i < nl.getLength(); i++) {
// creating new HashMap
System.out.println(nl.getLength());
HashMap<String, String> map = new HashMap<String, String> ();
map.put( KEY_TITLE,((Element)nl.item(i)).getAttribute("name"));
for (int j = 0; j < nl1.getLength(); j++) {
map.put( KEY_ARTICLE,((Element)nl1.item(j)).getAttribute("title"));
}
songsList.add(map);
}
Here i have to run the app means the article title is displayed.but the article title is didn't display correctly.my current o/p is looking like below:
Books
Krish Krish
Names
Krish Krish
The last article title is dispalyed on all categories.Why these error is occurring ??? please help me...how can i resolve these error ??? please provide me some ideas ???
EDIT:
I have changed my code like below:
public class MainActivity extends Activity {
static final String URL = "xxx";
static final String KEY_TITLE = "Category";
static final String KEY_ARTICLE = "article";
static final String KEY_IMAGE = "image";
LazyAdapter adapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ArrayList<HashMap<String, List<String>>> songsList = new ArrayList<HashMap<String, List<String>>>();
XMLParser parser = new XMLParser();
String xml = parser.getXmlFromUrl(URL); // getting XML from URL
Document doc = parser.getDomElement(xml); // getting DOM element
NodeList nl = doc.getElementsByTagName(KEY_TITLE);
NodeList nl1 = doc.getElementsByTagName(KEY_ARTICLE);
NodeList nl2 = doc.getElementsByTagName(KEY_IMAGE);
System.out.println(nl.getLength());
HashMap<String, List<String>> map = new HashMap<String, List<String>>();
for(int i = 0; i < nl.getLength(); i++) {
String name = ((Element) nl.item(i)).getAttribute("name");
populateMap(map, name, KEY_TITLE);
for(int j = 0; j < nl1.getLength(); j++) {
String title=((Element) nl1.item(j)).getAttribute("title");
populateMap(map, title, KEY_ARTICLE);
String url=((Element) nl2.item(j)).getAttribute("url");
populateMap(map, url, KEY_IMAGE);
}
songsList.add(map);
}
GridView list = (GridView) findViewById(R.id.listView1);
adapter = new LazyAdapter(this, songsList);
list.setAdapter(adapter);
private void populateMap(HashMap<String, List<String>> map, String value,
String key) {
// TODO Auto-generated method stub
List<String> myList;
if(!map.containsKey(key)) {
myList = new ArrayList<String>();
myList.add(value);
map.put(key, myList);
} else {
myList = map.get(key);
myList.add(value);
}
Now i have to run the app means am getting the o/p like below:
[Books,Names]
[Android,Java,PHP,Mysql,Dita,Frieda,Demi,Shyamalan,Krish] [Android,Java,PHP,Mysql,Dita,Frieda,Demi,Shyamalan,Krish]
[Books,Names]
[Android,Java,PHP,Mysql,Dita,Frieda,Demi,Shyamalan,Krish] [Android,Java,PHP,Mysql,Dita,Frieda,Demi,Shyamalan,Krish]
pls provide me some idea to get the correct o/p(my needed design).
This is my LazyAdpter file :
public class LazyAdapter extends BaseAdapter {
private Activity activity;
private ArrayList<HashMap<String, List<String>>> data;
private static LayoutInflater inflater = null;
public ImageLoader imageLoader;
ListAdapter listViewAdapter;
public LazyAdapter(Activity a, ArrayList<HashMap<String, List<String>>> songsList) {
activity = a;
data = songsList;
inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader = new ImageLoader(activity.getApplicationContext());
}
public int getCount() {
return data.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi = convertView;
vi = inflater.inflate(R.layout.list_row,parent, false);
TextView title = (TextView) vi.findViewById(R.id.title);
Gallery listview = (Gallery) vi .findViewById(R.id.model);
HashMap<String, List<String>> item = new HashMap<String, List<String>>();
item = data.get(position);
title.setText(item.get(MainActivity.KEY_TITLE).toString());
listViewAdapter = new ListAdapter(activity, data);
listview.setAdapter(listViewAdapter);
return vi;
}
This is ListAdapter class:
public View getView(int position, View convertView, ViewGroup parent) {
View vi = convertView;
vi = inflater.inflate(R.layout.listrow,parent, false);
TextView title = (TextView) vi.findViewById(R.id.textView1);
HashMap<String, List<String>> item = new HashMap<String, List<String>>();
item = data.get(position);
title.setText(item.get(MainActivity.KEY_ARTICLE).toString());
return vi;
}
回答1:
Map<String,List<String>> categoryToArticlesMap = new HashMap<String,List<String>>();
NodeList categoryNd = doc.getElementsByTagName("Category");
for (int i = 0; i < categoryNd.getLength(); i++)
{
Element e = (Element) categoryNd.item(i);
String categoryName = e.getAttribute("name");
NodeList articlesNd = e.getElementsByTagName("Articles");
Element e1 = (Element) articlesNd.item(0);
NodeList articleNd = e1.getElementsByTagName("article");
List<String> articles = new ArrayList<String>();
for (int j = 0; j < articleNd.getLength(); j++) {
Element articleNode = (Element) articleNd.item(j);
String articleName = articleNode.getAttribute("title");
articles.add(articleName);
}
categoryToArticlesMap.put(categoryName, articles);
}
This will give you the required output.
回答2:
Here in this line map.put( KEY_ARTICLE,((Element)nl1.item(j)).getAttribute("title")); you are over writing the previous value present in the map. Change ArrayList<HashMap<String, String>> songsList to ArrayList<HashMap<String, List<String>>> songsList and add each value to list and put it to the map.
Even if you do this you will get output as,
Books
Android Java PHP MySQL Dita Frieda Demi Shyamalan Krish
Names
Android Java PHP MySQL Dita Frieda Demi Shyamalan Krish
To get the desired output, you should consider the nodelist for article under each Category instead of getting all the article tags in the document.
来源：https://stackoverflow.com/questions/15737756/hashmap-in-android-xml-parsing