title: actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS) deprecated
body: <p>I'm following the tutorial <a href="https://www.youtube.com/watch?v=VVahIc8yENk" rel="noreferrer">https://www.youtube.com/watch?v=VVahIc8yENk</a> and I'm getting the error </p>
  
  <blockquote>
    <p>java.lang.NullPointerException: Attempt to invoke virtual method 'void
    android.app.ActionBar.setNavigationMode(int)' on a null object
    reference</p>
  </blockquote>
  
  <p>I'm using Android Studio to write this program and I have tried from API 11 to 21 and none of them work.  </p>
  
  <pre><code>public class Tabtest extends FragmentActivity implements ActionBar.TabListener {
  
      ActionBar actionBar;
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_tab_test);
  
          actionBar=getActionBar();
          actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
  
          ActionBar.Tab tab1=actionBar.newTab();
          tab1.setText("tab1");
          tab1.setTabListener(this);
  
          ActionBar.Tab tab2=actionBar.newTab();
          tab2.setText("tab2");
          tab2.setTabListener(this);
  
          ActionBar.Tab tab3=actionBar.newTab();
          tab3.setText("tab3");
          tab3.setTabListener(this);
  
          ActionBar.Tab tab4=actionBar.newTab();
          tab4.setText("tab4");
          tab4.setTabListener(this);
  
          actionBar.addTab(tab1);
          actionBar.addTab(tab2);
          actionBar.addTab(tab3);
          actionBar.addTab(tab4);
      }
  
      @Override
      public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
          Log.d("VIVZ", "onTabReselected at "+" position "+tab.getPosition()+" name "+tab.getText());
      }
  
      @Override
      public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction ft) {
          Log.d("VIVZ", "onTabReselected at "+" position "+tab.getPosition()+" name "+tab.getText());
      }
  
      @Override
      public void onTabReselected(ActionBar.Tab tab, FragmentTransaction ft) {
          Log.d("VIVZ", "onTabReselected at "+" position "+tab.getPosition()+" name "+tab.getText());
      }
  }
  </code></pre>