我的错误信息是：
>02-12 10:15:34.625: E/AndroidRuntime(1018): FATAL EXCEPTION: AsyncTask
> 1 02-12 10:15:34.625: E/AndroidRuntime(1018): java.lang.RuntimeException: An error occured while executing
> doInBackground() 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> android.os.AsyncTask$3.done(AsyncTask.java:200) 02-12 10:15:34.625:
> E/AndroidRuntime(1018): at
> java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> java.util.concurrent.FutureTask.setException(FutureTask.java:124)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> java.util.concurrent.FutureTask.run(FutureTask.java:137) 02-12
> 10:15:34.625: E/AndroidRuntime(1018): at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> java.lang.Thread.run(Thread.java:1096) 02-12 10:15:34.625:
> E/AndroidRuntime(1018): Caused by: java.lang.NullPointerException
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> se.gibk.gibk.MainActivity$PostTask.GetList(MainActivity.java:88) 02-12
> 10:15:34.625: E/AndroidRuntime(1018): at
> se.gibk.gibk.MainActivity$PostTask.doInBackground(MainActivity.java:143)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> se.gibk.gibk.MainActivity$PostTask.doInBackground(MainActivity.java:1)
> 02-12 10:15:34.625: E/AndroidRuntime(1018): at
> android.os.AsyncTask$2.call(AsyncTask.java:185) 02-12 10:15:34.625:
> E/AndroidRuntime(1018): at
> java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
我的代码是：
public class MainActivity extends Activity {
private static final String TAG = "Debugging";
private ListView list;
ArrayList<String> links;
Sermons sermons;
protected void onCreate(Bundle savedInstanceState) {
Log.d(TAG, "MainActivity - OnCreate()");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new PostTask(this).execute("http://gibk.se/sample-page/predikningar/?podcast");
Log.d(TAG, "execute");
}
公共类 PostTask 扩展 AsyncTask> {
private Context context;
public PostTask(Context context) {
this.context = context;
}
private ArrayList<Sermons> GetList(String url) {
Log.d(TAG, "GetList");
ArrayList<Sermons> results = new ArrayList<Sermons>();
try {
URL urls = new URL(url);
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xmlParser = factory.newPullParser();
xmlParser.setInput(this.getInputStream(urls), "UTF_8");
boolean insideItem = false;
int eventType = xmlParser.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_TAG) {
if (xmlParser.getName().equalsIgnoreCase("item")) {
sermons = new Sermons();
insideItem = true;
} else if (xmlParser.getName().equalsIgnoreCase("title")) {
if (insideItem)
sermons.setSermon(xmlParser.nextText());
} else if (xmlParser.getName().equalsIgnoreCase("itunes:author")) {
if (insideItem)
sermons.setPreacher(xmlParser.nextText());
} else if (xmlParser.getName().equalsIgnoreCase("guid")) {
if (insideItem)
links.add(xmlParser.nextText());
}
results.add(sermons);
}
else if(eventType==XmlPullParser.END_TAG && xmlParser.getName().equalsIgnoreCase("item")){
insideItem=false;
}
eventType = xmlParser.next();
}
}
catch (MalformedURLException e) {
e.printStackTrace();
}
catch (XmlPullParserException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
return results;
}
private InputStream getInputStream(URL url) {
try {
return url.openConnection().getInputStream();
} catch (IOException e) {
return null;
}
}
@Override
protected ArrayList<Sermons> doInBackground(String... params) {
Log.d(TAG, "doInBackGround");
String url = params[0];
ArrayList<Sermons> sermon = this.GetList(url);
return sermon;
}
@Override
protected void onPostExecute(ArrayList<Sermons> result) {
super.onPostExecute(result);
Log.d(TAG, "onPostExecute");
links = new ArrayList<String>();
list = (ListView) findViewById(R.id.list);
list.setAdapter(new Adapter(MainActivity.this, (ArrayList<Sermons>) result));
list.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View v, int position,
long arg3) {
Uri uri = Uri.parse(links.get(position));
String url = uri.toString();
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(url));
startActivity(intent);
}
});
}
} }