スレッド非同期例外、AyncTask＃2致命的なエラーで終了する

Question

RSSニュースリーダーアプリケーションを作成しようとしていて、RSSフィードリストに新しいWebサイトを追加するためにスレッドを使用するAsyncTaskを使用しています。しかし、新しいURLを入力して「追加」を押すと、アプリがクラッシュします。 LogCat氏は述べています -

は12スレッドID：スレッドがキャッチされない例外で終了」、 "AsyncTask＃2致命的な例外" とjava.Lang.RuntimeException：エラーdoInBackgroundの実行中に（）

助けてください！ （私はADTを使用していますPS。）

package com.rssnews; 

import android.app.Activity; 
import android.app.ProgressDialog; 
import android.content.Intent; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
import java.lang.Exception; 

public class AddNewFeed extends Activity { 
Button btnSubmit; 
Button btnCancel; 
EditText txtUrl; 
TextView textViewMessage; 

RSSParser rssParser = new RSSParser(); 
RSSFeed rssFeed; 

private ProgressDialog pDialog; 

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

    btnSubmit = (Button) findViewById(R.id.btnSubmit); 
    btnCancel = (Button) findViewById(R.id.btnCancel); 
    txtUrl = (EditText) findViewById(R.id.txtUrl); 
    textViewMessage = (TextView) findViewById(R.id.textViewMessage); 

    btnSubmit.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      try{ 
      String url = txtUrl.getText().toString(); 
      Log.d("URL Length", "" + url.length()); 
      if (url.length() > 0) { 
       textViewMessage.setText(""); 
       String urlPattern = "^http(s{0,1})://[a-zA-Z0-9_/\\-\\.]+\\.([A-Za-z/]{2,5})[a-zA-Z0-9_/\\&\\?\\=\\-\\.\\~\\%]*"; 
       if (url.matches(urlPattern)) { 
        new loadRSSFeed().execute(url); 
       } else { 
        textViewMessage.setText("Please enter a valid url"); 
       } 
      } else { 
       textViewMessage.setText("Please enter website url"); 
      }} 
      catch(Exception e){ 
       finish(); 
      } 
     } 
    }); 

    btnCancel.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      finish(); 
     } 
    }); 
} 

/** 
* Background Async Task to get RSS data from URL 
* */ 
class loadRSSFeed extends AsyncTask<String, String, String> { 

    /** 
    * Before starting background thread Show Progress Dialog 
    * */ 
    @Override 
    protected void onPreExecute() { 
     super.onPreExecute(); 
     pDialog = new ProgressDialog(AddNewFeed.this); 
     pDialog.setMessage("Fetching RSS Information ..."); 
     pDialog.setIndeterminate(false); 
     pDialog.setCancelable(false); 
     pDialog.show(); 

    } 

    /** 
    * getting 
    * */ 
    @Override 
    protected String doInBackground(String... args) { 
     String url = args[0]; 
     rssFeed = rssParser.getRSSFeed(url); 
     Log.d("rssFeed", " " + rssFeed); 
     if (rssFeed != null) { 
      Log.e("RSS URL", 
        rssFeed.getTitle() + "" + rssFeed.getLink() + "" 
          + rssFeed.getDescription() + "" 
          + rssFeed.getLanguage()); 
      RSSDatabaseHandler rssDb = new RSSDatabaseHandler(
        getApplicationContext()); 
      WebSite site = new WebSite(rssFeed.getTitle(), 
        rssFeed.getLink(), rssFeed.getRSSLink(), 
        rssFeed.getDescription()); 
      rssDb.addSite(site); 
      Intent i = new Intent(getApplicationContext(), 
        RSSNewsReaderPBActivity.class); 
      // send result code 100 to notify about product update 
      setResult(100, i); 
      startActivity(i); 
      return null; 
     } else { 
      runOnUiThread(new Runnable() { 
       public void run() { 
        textViewMessage 
          .setText("Rss url not found. Please check the url or try again"); 
       } 
      }); 
     } 
     return null; 
    } 

    /** 
    * After completing background task Dismiss the progress dialog 
    * **/ 
    protected void onPostExecute(String args) { 
     pDialog.dismiss(); 
     runOnUiThread(new Runnable() { 
      public void run() { 
       if (rssFeed != null) { 
       } 
      } 
     }); 
    } 
} 

@Override 
protected void onPause() { 
    super.onPause(); 
    //pDialog.dismiss(); 
    finish(); 
} 

@Override 
public void onBackPressed() { 
    finish(); 
} 

}

04-10 13:28:50.250: W/dalvikvm(1853): threadid=12: thread exiting with uncaught exception (group=0xb1a1bb90) 
04-10 13:28:50.350: E/AndroidRuntime(1853): FATAL EXCEPTION: AsyncTask #2 
04-10 13:28:50.350: E/AndroidRuntime(1853): Process: com.rssnews, PID: 1853 
04-10 13:28:50.350: E/AndroidRuntime(1853): java.lang.RuntimeException: An error occured while executing doInBackground() 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at android.os.AsyncTask$3.done(AsyncTask.java:300) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.FutureTask.run(FutureTask.java:242) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.lang.Thread.run(Thread.java:841) 
04-10 13:28:50.350: E/AndroidRuntime(1853): Caused by: java.lang.NoClassDefFoundError: org.jsoup.Jsoup 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at com.rssnews.RSSParser.getRSSLinkFromURL(RSSParser.java:129) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at com.rssnews.RSSParser.getRSSFeed(RSSParser.java:52) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at com.rssnews.AddNewFeed$loadRSSFeed.doInBackground(AddNewFeed.java:90) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at com.rssnews.AddNewFeed$loadRSSFeed.doInBackground(AddNewFeed.java:1) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at android.os.AsyncTask$2.call(AsyncTask.java:288) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  at java.util.concurrent.FutureTask.run(FutureTask.java:237) 
04-10 13:28:50.350: E/AndroidRuntime(1853):  ... 3 more 
04-10 13:28:50.700: I/Choreographer(1853): Skipped 38 frames! The application may be doing too much work on its main thread. 
04-10 13:28:51.880: I/Choreographer(1853): Skipped 95 frames! The application may be doing too much work on its main thread. 
04-10 13:28:55.320: I/Choreographer(1853): Skipped 49 frames! The application may be doing too much work on its main thread. 
04-10 13:28:56.280: I/Choreographer(1853): Skipped 96 frames! The application may be doing too much work on its main thread. 
04-10 13:28:57.920: E/WindowManager(1853): android.view.WindowLeaked: Activity com.rssnews.AddNewFeed has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b2524248 V.E..... R.....I. 0,0-563,230} that was originally added here 
04-10 13:28:57.920: E/WindowManager(1853): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:346) 
04-10 13:28:57.920: E/WindowManager(1853): at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248) 
04-10 13:28:57.920: E/WindowManager(1853): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69) 
04-10 13:28:57.920: E/WindowManager(1853): at android.app.Dialog.show(Dialog.java:286) 
04-10 13:28:57.920: E/WindowManager(1853): at com.rssnews.AddNewFeed$loadRSSFeed.onPreExecute(AddNewFeed.java:80) 
04-10 13:28:57.920: E/WindowManager(1853): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587) 
04-10 13:28:57.920: E/WindowManager(1853): at android.os.AsyncTask.execute(AsyncTask.java:535) 
04-10 13:28:57.920: E/WindowManager(1853): at com.rssnews.AddNewFeed$1.onClick(AddNewFeed.java:45) 
04-10 13:28:57.920: E/WindowManager(1853): at android.view.View.performClick(View.java:4424) 
04-10 13:28:57.920: E/WindowManager(1853): at android.view.View$PerformClick.run(View.java:18383) 
04-10 13:28:57.920: E/WindowManager(1853): at android.os.Handler.handleCallback(Handler.java:733) 
04-10 13:28:57.920: E/WindowManager(1853): at android.os.Handler.dispatchMessage(Handler.java:95) 
04-10 13:28:57.920: E/WindowManager(1853): at android.os.Looper.loop(Looper.java:137) 
04-10 13:28:57.920: E/WindowManager(1853): at android.app.ActivityThread.main(ActivityThread.java:4998) 
04-10 13:28:57.920: E/WindowManager(1853): at java.lang.reflect.Method.invokeNative(Native Method) 
04-10 13:28:57.920: E/WindowManager(1853): at java.lang.reflect.Method.invoke(Method.java:515) 
04-10 13:28:57.920: E/WindowManager(1853): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777) 
04-10 13:28:57.920: E/WindowManager(1853): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593) 
04-10 13:28:57.920: E/WindowManager(1853): at dalvik.system.NativeStart.main(Native Method) 
04-10 13:28:57.980: I/Choreographer(1853): Skipped 62 frames! The application may be doing too much work on its main thread. 
04-10 13:29:00.400: I/Process(1853): Sending signal. PID: 1853 SIG: 9 

Answer 1

バックグラウンドスレッド（doInBackgroundメソッド内）からアクティビティを開始しようとしています。これが、アプリがクラッシュする理由です。そのコードをonPostExecuteに追加する必要があります。

protected void onPostExecute(String args) { 
    pDialog.dismiss(); 
    Intent i = new Intent(getApplicationContext(), RSSNewsReaderPBActivity.class); 
    setResult(100, i); 
    startActivity(i); 
}