title: webview and listview in same activity
body: <p>i'm trying to make a webview and listview in a same activity. 
  here's my layout file :</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical"
  android:background="@android:color/white" &gt;
  
  &lt;com.markupartist.android.widget.ActionBar
      android:id="@+id/actionbar"
      style="@style/ActionBar" /&gt;
  
  &lt;WebView
      android:id="@+id/webView1"
      android:layout_width="match_parent"
      android:layout_height="210dp" /&gt;
  
  &lt;ListView
      android:id="@+id/listtest"
      android:layout_width="match_parent"
      android:layout_height="wrap_content" &gt;
  &lt;/ListView&gt;
  
  &lt;TextView 
      android:id="@+id/tv_test2"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:padding="10dp"
      android:textSize="16sp"/&gt;
  </code></pre>
  
  <p></p>
  
  <p>and here's my row layout :</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="@android:color/white"
  android:orientation="vertical" &gt;
  
  &lt;com.markupartist.android.widget.ActionBar
      android:id="@+id/actionbar"
      style="@style/ActionBar" /&gt;
  
  &lt;TextView
      android:id="@+id/tv_test"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:padding="10dp"
      android:textSize="16sp" &gt;
  &lt;/TextView&gt;
  </code></pre>
  
  <p></p>
  
  <p>and here's my activity :</p>
  
  <pre><code>public class Tab_Bike_Information_Activity extends Activity {
  WebView mWebView;
  TextView tv;
  private ListView mainListView;
  private ArrayAdapter&lt;String&gt; listAdapter;
  
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.tessss);
  
      final ActionBar actionBar = (ActionBar) findViewById(R.id.actionbar);
      actionBar.setTitle(getString(R.string.app_name));
  
      int index = getIntent().getIntExtra("text", 0);
  
      mWebView = (WebView) findViewById(R.id.webView1);
  
      String temp = "&lt;html&gt;&lt;body&gt;" + "&lt;p align=\"justify\"&gt;"
              + getString(R.string.xc_info + index) + "&lt;/p&gt; "
              + "&lt;/body&gt;&lt;/html&gt;";
      mWebView.loadData(temp, "text/html", "utf-8");
  
  
      mainListView = (ListView) findViewById(android.R.id.list );  
  
      // Create and populate a List of planet names.  
      String[] planets = new String[] { "Mercury", "Venus", "Earth", "Mars",  
                                        "Jupiter", "Saturn", "Uranus", "Neptune"};    
      ArrayList&lt;String&gt; planetList = new ArrayList&lt;String&gt;();  
      planetList.addAll( Arrays.asList(planets) );  
  
      // Create ArrayAdapter using the planet list.  
      listAdapter = new ArrayAdapter&lt;String&gt;(this, R.layout.tessss_row, planetList);  
  
      // Add more planets. If you passed a String[] instead of a List&lt;String&gt;   
      // into the ArrayAdapter constructor, you must not add more items.   
      // Otherwise an exception will occur.  
      listAdapter.add( "Ceres" );  
      listAdapter.add( "Pluto" );  
      listAdapter.add( "Haumea" );  
      listAdapter.add( "Makemake" );  
      listAdapter.add( "Eris" );  
  
  
      tv = (TextView) findViewById(R.id.tv_test);
  
  }
  </code></pre>
  
  <p>and here's the logcat :</p>
  
  <pre><code>09-19 20:04:04.659: E/AndroidRuntime(13951): FATAL EXCEPTION: main
  09-19 20:04:04.659: E/AndroidRuntime(13951): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.wilis.hellotabwidget/com.wilis.hellotabwidget.Tab_Bike_Information_Activity}: java.lang.NullPointerException
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.os.Handler.dispatchMessage(Handler.java:99)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.os.Looper.loop(Looper.java:130)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread.main(ActivityThread.java:3687)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at java.lang.reflect.Method.invokeNative(Native Method)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at java.lang.reflect.Method.invoke(Method.java:507)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at dalvik.system.NativeStart.main(Native Method)
  09-19 20:04:04.659: E/AndroidRuntime(13951): Caused by: java.lang.NullPointerException
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at com.wilis.hellotabwidget.Tab_Bike_Information_Activity.onCreate(Tab_Bike_Information_Activity.java:75)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
  09-19 20:04:04.659: E/AndroidRuntime(13951):    ... 11 more
  </code></pre>
  
  <p>can anybody help with this? thanks</p>