<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/menu_search"
          android:title="@string/menu_search"
          android:icon="@drawable/ic_menu_search"
          android:showAsAction="ifRoom|collapseActionView"//表明需要嵌入一个button中，当用户点击该按钮，view展开。
          android:actionViewClass="android.widget.SearchView" />
</menu>

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.options, menu);
    SearchView searchView = (SearchView) menu.findItem(R.id.menu_search).getActionView();
    // Configure the search info and add any event listeners
    ...
    return super.onCreateOptionsMenu(menu);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.options, menu);
    MenuItem menuItem = menu.findItem(R.id.actionItem);
    ...
 
    menuItem.setOnActionExpandListener(new OnActionExpandListener() {
        @Override
        public boolean onMenuItemActionCollapse(MenuItem item) {
            // Do something when collapsed
            return true;  // Return true to collapse action view
        }
 
        @Override
        public boolean onMenuItemActionExpand(MenuItem item) {
            // Do something when expanded
            return true;  // Return true to expand action view
        }
    });
}

public static class TabListener<T extends Fragment> implements ActionBar.TabListener {
    private Fragment mFragment;
    private final Activity mActivity;
    private final String mTag;
    private final Class<T> mClass;
 
    /** Constructor used each time a new tab is created.
      * @param activity  The host Activity, used to instantiate the fragment
      * @param tag  The identifier tag for the fragment
      * @param clz  The fragment‘s Class, used to instantiate the fragment
      */
    public TabListener(Activity activity, String tag, Class<T> clz) {
        mActivity = activity;
        mTag = tag;
        mClass = clz;
    }
 
    /* The following are each of the ActionBar.TabListener callbacks */
 
    public void onTabSelected(Tab tab, FragmentTransaction ft) {
        // Check if the fragment is already initialized
        if (mFragment == null) {
            // If not, instantiate and add it to the activity
            mFragment = Fragment.instantiate(mActivity, mClass.getName());
            ft.add(android.R.id.content, mFragment, mTag);
        } else {
            // If it exists, simply attach it in order to show it
            ft.attach(mFragment);
        }
    }
 
    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        if (mFragment != null) {
            // Detach the fragment, because another one is being attached
            ft.detach(mFragment);
        }
    }
 
    public void onTabReselected(Tab tab, FragmentTransaction ft) {
        // User selected the already selected tab. Usually do nothing.
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Notice that setContentView() is not used, because we use the root
    // android.R.id.content as the container for each fragment
 
    // setup action bar for tabs
    ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
    actionBar.setDisplayShowTitleEnabled(false);
 
    Tab tab = actionBar.newTab()
            .setText(R.string.artist)
            .setTabListener(new TabListener<ArtistFragment>(
                    this, "artist", ArtistFragment.class));
    actionBar.addTab(tab);
 
    tab = actionBar.newTab()
        .setText(R.string.album)
        .setTabListener(new TabListener<AlbumFragment>(
                this, "album", AlbumFragment.class));
    actionBar.addTab(tab);
}

SpinnerAdapter mSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.action_list,
          android.R.layout.simple_spinner_dropdown_item);

mOnNavigationListener = new OnNavigationListener() {
  // Get the same strings provided for the drop-down‘s ArrayAdapter
  String[] strings = getResources().getStringArray(R.array.action_list);
 
  @Override
  public boolean onNavigationItemSelected(int position, long itemId) {
    // Create new fragment from our own Fragment class
    ListContentFragment newFragment = new ListContentFragment();
    FragmentTransaction ft = openFragmentTransaction();
    // Replace whatever is in the fragment container with this fragment
    //  and give the fragment a tag name equal to the string at the position selected
    ft.replace(R.id.fragment_container, newFragment, strings[position]);
    // Apply changes
    ft.commit();
    return true;
  }
};

action bar的样式

<SomeView
    ...
    android:layout_marginTop="?android:attr/actionBarSize" />