title: Error inflating class fragment - duplicate id/illegalargumentexception?
body: <p>I'm trying make an app that I'm building take a search term from the main activity, return results, and then have the results be clickable such that a detail could be viewed from each results.  I'm doing this by using a MainActivity, a ResultsActivity, and PlaceActivity and then a ListFragmentClickable (which extends ListFragment).  If the handset is oriented in portrait mode, the results list should be viewable, with the details being viewed only if a result is clicked.  If the handset is landscape, a detail window should pop up to the right of the list when an item is selected.</p>
  
  <p>At runtime, I get an error that reads "error inflating class fragment".  I have no idea what is causing it, and I'd love help in getting rid of it.</p>
  
  <p>My ListFragmentClickables are called by my ResultsActivity, which is here:</p>
  
  <pre><code>public class ResultsActivity extends FragmentActivity implements ListFragmentClickable.OnItemSelectedListener{
  
  private ArrayAdapter&lt;String&gt; mAdapter;
  
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_results_view);
  
      //Receive searchTerm from MainActivity
      Intent intent = getIntent();
      String searchTerm = intent.getStringExtra(MainActivity.SEARCH_TERM);
  
      mAdapter = new ArrayAdapter&lt;String&gt;(this, R.layout.item_label_list);
  
      FragmentManager     fm = getSupportFragmentManager();
      FragmentTransaction ft = fm.beginTransaction();
  
      FactualResponderFragment responder = (FactualResponderFragment) fm.findFragmentByTag("RESTResponder");
      if (responder == null) {
          responder = new FactualResponderFragment();
          ft.add(responder, "RESTResponder");
      }
  
      Bundle bundle = new Bundle();
      bundle.putString("search_term", searchTerm);
      responder.setArguments(bundle);
  
      ft.commit();
  }
  
  public ArrayAdapter&lt;String&gt; getArrayAdapter() {
      return mAdapter;
  }
  
  @Override //creates a DetailFragment when a list item is selected
  public void onItemSelected(String link) {
      DetailFragment fragment = (DetailFragment) getSupportFragmentManager().findFragmentById(R.id.detailFragment);
      if (fragment != null &amp;&amp; fragment.isInLayout()) {
            fragment.setText(link);
      } else {
        Intent intent = new Intent(getApplicationContext(), PlaceActivity.class);
            intent.putExtra(PlaceActivity.EXTRA_URL, link);
        startActivity(intent);
      }
  }
  </code></pre>
  
  <p>}</p>
  
  <p>Here's the ListFragmentClickable class:</p>
  
  <pre><code>public class ListFragmentClickable extends ListFragment{
  
    private OnItemSelectedListener listener;
  
  
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
        View view = inflater.inflate(R.layout.activity_results_view, container, false);
        return view;
    }
  
    @Override
        public void onListItemClick(ListView l, View v, int position, long id) {
            updateDetail(); //see bottom
        }
  
    public interface OnItemSelectedListener {
        public void onItemSelected(String link);
    }
  
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        if (activity instanceof OnItemSelectedListener) {
            listener = (OnItemSelectedListener) activity;
        } else {
            throw new ClassCastException(activity.toString()
              + " must implemenet ListFragmentClickable.OnItemSelectedListener");
        }
    }
  
  
   public void updateDetail() {
          // Create fake data
      String newTime = String.valueOf(System.currentTimeMillis());
      // Send data to Activity
      listener.onItemSelected(newTime); //should direct PlaceActivity!!
    }
  }
  </code></pre>
  
  <p>Here's my layout file for the ResultsActivity (activity_results_activity.xml):</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:orientation="horizontal" &gt;
  
  &lt;fragment
      android:id="@+id/fragment_content"
      android:layout_width="0dp"
      android:layout_weight="1"
      android:layout_height="match_parent"
      android:layout_marginTop="?android:attr/actionBarSize"
      class="com.example.blobtag2.ListFragmentClickable" &gt;&lt;/fragment&gt;
  
  
  &lt;ListView
      android:id="@android:id/list"
      android:layout_width="fill_parent"
      android:layout_height="50dp"
      android:divider="#b5b5b5"
      android:dividerHeight="1dp"&gt;&lt;/ListView&gt;
  
  &lt;/LinearLayout&gt; 
  </code></pre>
  
  <p>And finally here's the log:</p>
  
  <pre><code>03-21 22:32:03.297: E/AndroidRuntime(764): FATAL EXCEPTION: main
  03-21 22:32:03.297: E/AndroidRuntime(764): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.blobtag2/com.example.blobtag2.ResultsActivity}: android.view.InflateException: Binary XML file line #7: Error inflating class fragment
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.os.Handler.dispatchMessage(Handler.java:99)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.os.Looper.loop(Looper.java:137)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread.main(ActivityThread.java:4745)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at java.lang.reflect.Method.invokeNative(Native Method)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at java.lang.reflect.Method.invoke(Method.java:511)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at dalvik.system.NativeStart.main(Native Method)
  03-21 22:32:03.297: E/AndroidRuntime(764): Caused by: android.view.InflateException: Binary XML file line #7: Error inflating class fragment
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at com.example.blobtag2.ListFragmentClickable.onCreateView(ListFragmentClickable.java:32)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:846)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1061)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1160)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:272)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:676)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:256)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.Activity.setContentView(Activity.java:1867)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at com.example.blobtag2.ResultsActivity.onCreate(ResultsActivity.java:37)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.Activity.performCreate(Activity.java:5008)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
  03-21 22:32:03.297: E/AndroidRuntime(764):  ... 11 more
  03-21 22:32:03.297: E/AndroidRuntime(764): Caused by: java.lang.IllegalArgumentException: Binary XML file line #7: Duplicate id 0x7f070003, tag null, or parent id 0x0 with another fragment for com.example.blobtag2.ListFragmentClickable
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:277)
  03-21 22:32:03.297: E/AndroidRuntime(764):  at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:676)
  03-21 22:32:03.297: E/AndroidRuntime(764):  ... 30 more
  </code></pre>
  
  <p>Any and all help is greatly, greatly appreciated.  Please let me know if there's anything else I can add?</p>