我有一个 xml 解析器，它在模拟器中的 Android api 8 和 10 上运行良好（我的设备上有 api 10 并且运行良好）但尝试模拟更高的 api 并在 http 请求上给我错误。这是 Parser.class：
package com.muc.horoscop;
import java.io.IOException;
import java.io.StringReader;
import java.io.UnsupportedEncodingException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.auth.BasicScheme;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import android.util.Log;
public class XMLParser {
public XMLParser() {
}
/**
* Getting XML from URL making HTTP request
* @param url string
* */
public String getXmlFromUrl(String url) {
String xml = new String();
try {
// defaultHttpClient
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
// httpPost.addHeader(BasicScheme.authenticate(
// new UsernamePasswordCredentials("client_ro", "+_lklklkl*/544pF"),"UTF-8", false));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
xml = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// return XML
return xml;
}
/**
* Getting XML DOM element
* @param XML string
* */
public Document getDomElement(String xml){
Document doc = null;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xml));
doc = db.parse(is);
} catch (ParserConfigurationException e) {
Log.e("Error: ", e.getMessage());
return null;
} catch (SAXException e) {
Log.e("Error: ", e.getMessage());
return null;
} catch (IOException e) {
Log.e("Error: ", e.getMessage());
return null;
}
return doc;
}
/** Getting node value
* @param elem element
*/
public final String getElementValue( Node elem ) {
Node child;
if( elem != null){
if (elem.hasChildNodes()){
for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
if( child.getNodeType() == Node.TEXT_NODE ){
return child.getNodeValue();
}
}
}
}
return "";
}
/**
* Getting node value
* @param Element node
* @param key string
* */
public String getValue(Element item, String str) {
NodeList n = item.getElementsByTagName(str);
return this.getElementValue(n.item(0));
}
}
这是 LogCat
12-31 11:23:31.223: D/AndroidRuntime(442): Shutting down VM
12-31 11:23:31.223: W/dalvikvm(442): threadid=1: thread exiting with uncaught exception (group=0x40014760)
12-31 11:23:31.243: E/AndroidRuntime(442): FATAL EXCEPTION: main
12-31 11:23:31.243: E/AndroidRuntime(442): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.muc.horoscop/com.muc.horoscop.AfisareHoroscop}: android.os.NetworkOnMainThreadException
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1815)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1831)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread.access$500(ActivityThread.java:122)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1024)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.os.Handler.dispatchMessage(Handler.java:99)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.os.Looper.loop(Looper.java:132)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread.main(ActivityThread.java:4123)
12-31 11:23:31.243: E/AndroidRuntime(442): at java.lang.reflect.Method.invokeNative(Native Method)
12-31 11:23:31.243: E/AndroidRuntime(442): at java.lang.reflect.Method.invoke(Method.java:491)
12-31 11:23:31.243: E/AndroidRuntime(442): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
12-31 11:23:31.243: E/AndroidRuntime(442): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
12-31 11:23:31.243: E/AndroidRuntime(442): at dalvik.system.NativeStart.main(Native Method)
12-31 11:23:31.243: E/AndroidRuntime(442): Caused by: android.os.NetworkOnMainThreadException
12-31 11:23:31.243: E/AndroidRuntime(442): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1077)
12-31 11:23:31.243: E/AndroidRuntime(442): at java.net.InetAddress.lookupHostByName(InetAddress.java:477)
12-31 11:23:31.243: E/AndroidRuntime(442): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:277)
12-31 11:23:31.243: E/AndroidRuntime(442): at java.net.InetAddress.getAllByName(InetAddress.java:249)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:136)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
12-31 11:23:31.243: E/AndroidRuntime(442): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
12-31 11:23:31.243: E/AndroidRuntime(442): at com.muc.horoscop.XMLParser.getXmlFromUrl(XMLParser.java:52)
12-31 11:23:31.243: E/AndroidRuntime(442): at com.muc.horoscop.AfisareHoroscop.onCreate(AfisareHoroscop.java:111)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.Activity.performCreate(Activity.java:4397)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1048)
12-31 11:23:31.243: E/AndroidRuntime(442): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1779)
12-31 11:23:31.243: E/AndroidRuntime(442): ... 11 more
以及创建列表的活动类：
public class AfisareHoroscop extends ListActivity {
static final String KEY_ITEM = "item"; // parent node
static final String KEY_ID = "id";
static final String KEY_DATA = "data";
static final String KEY_SCURT = "scurt";
static final String KEY_DESC = "descriere";
@Override
public void onBackPressed() {
finish();
}
public boolean isOnline() {
ConnectivityManager cm =
(ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
if (netInfo != null && netInfo.isConnectedOrConnecting()) {
return true;
}
return false;
}
@Override
public void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
final String lala = getSharedPreferences("zodialui", MODE_PRIVATE).getString("zodia_consumator", "");
final String url = "http://calina.mucomputers.eu/"+lala+".xml";
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_afisare_horoscop);
//afisare titlu
getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.window_title);
final String tit_gen = getApplicationContext().getResources().getString(R.string.titlu_gen);
final TextView myTitleText = (TextView) findViewById(R.id.titlu);
String titlul = new String(tit_gen+" "+lala);
SpannableString spanString = new SpannableString(titlul);
spanString.setSpan(new StyleSpan(Typeface.BOLD), 0, spanString.length(), 0);
myTitleText.setText(spanString);
ImageView semn_titlu = (ImageView) findViewById(R.id.imageView2);
if (lala.equals("Balanta")) {
semn_titlu.setImageResource(R.drawable.balanta);
}else if (lala.equals("Berbec")){
semn_titlu.setImageResource(R.drawable.berbec);
}else if (lala.equals("Capricorn")){
semn_titlu.setImageResource(R.drawable.capricorn);
}else if (lala.equals("Fecioara")){
semn_titlu.setImageResource(R.drawable.fecioara);
}else if (lala.equals("Gemeni")){
semn_titlu.setImageResource(R.drawable.gemeni);
}else if (lala.equals("Leu")){
semn_titlu.setImageResource(R.drawable.leu);
}else if (lala.equals("Pesti")){
semn_titlu.setImageResource(R.drawable.pesti);
}else if (lala.equals("Rac")){
semn_titlu.setImageResource(R.drawable.rac);
}else if (lala.equals("Sagetator")){
semn_titlu.setImageResource(R.drawable.sagetator);
}else if (lala.equals("Scorpion")){
semn_titlu.setImageResource(R.drawable.scorpion);
}else if (lala.equals("Taur")){
semn_titlu.setImageResource(R.drawable.taur);
}else if (lala.equals("Varsator")){
semn_titlu.setImageResource(R.drawable.varsator);
}
//afisare titlu
if (isOnline() == true) {
ArrayList<HashMap<String, String>> menuItems = new ArrayList<HashMap<String, String>>();
XMLParser parser = new XMLParser();
String xml = parser.getXmlFromUrl(url); // getting XML
Document doc = parser.getDomElement(xml); // getting DOM element
NodeList nl = doc.getElementsByTagName(KEY_ITEM);
// looping through all item nodes <item>
for (int i = 0; i < nl.getLength(); i++) {
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
Element e = (Element) nl.item(i);
// adding each child node to HashMap key => value
map.put(KEY_DATA, parser.getValue(e, KEY_DATA));
map.put(KEY_SCURT, parser.getValue(e, KEY_SCURT));
map.put(KEY_DESC, parser.getValue(e, KEY_DESC));
// adding HashList to ArrayList
menuItems.add(map);
}
// Adding menuItems to ListView
ListAdapter adapter = new SimpleAdapter(this, menuItems,
R.layout.list_item,
new String[] { KEY_SCURT, KEY_DATA, KEY_DESC }, new int[] {
R.id.scurt, R.id.data, R.id.descriere });
setListAdapter(adapter);
Collections.reverse(menuItems);
// selecting single ListView item
ListView lv = getListView();
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String scurt = ((TextView) view.findViewById(R.id.scurt)).getText().toString();
String data = ((TextView) view.findViewById(R.id.data)).getText().toString();
String descriere = ((TextView) view.findViewById(R.id.descriere)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
in.putExtra(KEY_SCURT, scurt);
in.putExtra(KEY_DATA, data);
in.putExtra(KEY_DESC, descriere);
startActivity(in);
}
});
} else {
Button btn = new Button(this);
View.OnClickListener myhandler = new View.OnClickListener() {
public void onClick(View v) {
Intent i = new Intent(AfisareHoroscop.this, AfisareHoroscop.class); //your class
startActivity(i);
finish();
}
};
btn.setOnClickListener(myhandler);
btn.setText("Refresh");
RelativeLayout.LayoutParams paramsd = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT ,LayoutParams.WRAP_CONTENT);
paramsd.addRule(RelativeLayout.CENTER_IN_PARENT);
paramsd.height = 60;
paramsd.width = 60;
btn.setLayoutParams(paramsd);
addContentView(btn,paramsd);
Context context = getApplicationContext();
String no_con = getResources().getString(R.string.no_connection);
CharSequence text = no_con;
int duration = Toast.LENGTH_SHORT;
Toast toast = Toast.makeText(context, text, duration);
toast.show();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_afisare_horoscop, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_settings:
Intent menu_set = new Intent (this, MainActivity.class);
finish();
startActivity(menu_set);
return true;
case R.id.menu_despre:
startActivity(new Intent(this, DespreActivity.class));
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
我花了 2 天的时间来了解发生了什么，这可能是因为我是初学者。谢谢！