title: FragmentActivity cannot be resolved to a type
body: <p>I'm trying the application from <a href="http://android-developers.blogspot.com/2011/02/android-30-fragments-api.html" rel="nofollow noreferrer">this blog</a>. While extending the <code>FragmentActivity</code>, I'm getting the following error:</p>
  
  <pre><code>`FragmentActivity` was not able to resolve.
  </code></pre>
  
  <p>Am I missing any library or anything else?</p>
  
  <p>My code:</p>
  
  <pre><code>public class Testing_newActivity extends FragmentActivity { // here the FragmentActivity getting error package not found for import
      /** Called when the activity is first created. */
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          //setContentView(R.layout.main);
          if (getResources().getConfiguration().orientation
                  == Configuration.ORIENTATION_LANDSCAPE) {
              // If the screen is now in landscape mode, we can show the
              // dialog in-line so we don't need this activity.
              finish();
              return;
          }
  
          if (savedInstanceState == null) {
              // During initial setup, plug in the details fragment.
              DetailsFragment details = new DetailsFragment();
              details.setArguments(getIntent().getExtras());
  
              getSupportFragmentManager().beginTransaction().add(
                      android.R.id.content, details).commit();
          }       
      }
  }
  </code></pre>
  
  <p>android manifest file</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.searce.testingnew"
      android:versionCode="1"
      android:versionName="1.0" &gt;
  
      &lt;uses-sdk android:minSdkVersion="11" /&gt;
  
      &lt;application android:icon="@drawable/ic_launcher" android:label="@string/app_name" &gt;
          &lt;activity android:label="@string/app_name" android:name=".Testing_newActivity" &gt;
              &lt;intent-filter &gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
      &lt;/application&gt;
  
  &lt;/manifest&gt;
  </code></pre>