利用Actionbar同样可以很轻松的实现下拉式的导航方式，相比与tab的方式下拉式的导航方式更类型于html中的标签。若想实现这种效果：1)actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST) 2)setListNavigationCallbacks(SpinnerAdapter adapter,ActionBar.OnNavigationListener callback). 首先是创建一个Fragment类：

01 packageccom.app.main; 02 03 importandroid.annotation.SuppressLint; 04 importandroid.app.Fragment; 05 importandroid.content.Context; 06 importandroid.os.Bundle; 07 importandroid.view.LayoutInflater; 08 importandroid.view.View; 09 importandroid.view.ViewGroup; 10 importandroid.view.ViewGroup.LayoutParams; 11 importandroid.widget.TextView; 12 13 @SuppressLint("NewApi") 14 publicclassMyFragmentextendsFragment { 15 16 @Override 17 publicView onCreateView(LayoutInflater inflater, ViewGroup container, 18 Bundle savedInstanceState) { 19 20 Context context =this.getActivity(); 21 22 TextView tv =newTextView(context); 23 24 Bundle arc =this.getArguments(); 25 26 inttabs=arc.getInt("key"); 27 28 tv.setLayoutParams(newLayoutParams(LayoutParams.FILL_PARENT, 29 LayoutParams.WRAP_CONTENT)); 30 31 tv.setText("hello actionbar "+tabs); 32 33 returntv; 34 35 } 36 37 }

main.xml:

01 <RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android" 02 xmlns:tools="http://schemas.android.com/tools" 03 android:layout_width="match_parent" 04 android:layout_height="match_parent" 05 tools:context=".Main"> 06 07 <LinearLayout 08 android:id="@+id/content" 09 android:layout_width="match_parent" 10 android:layout_height="match_parent" 11 android:orientation="vertical"/> 12

13 </RelativeLayout>

自定义的用于显示textview的mytextview.xml:

01 <?xmlversion="1.0"encoding="utf-8"?> 02 <TextViewxmlns:android="http://schemas.android.com/apk/res/android" 03 android:id="@+id/text1" 04 android:textColor="#fff" 05 android:background="#696969" 06 android:layout_width="60sp" 07 android:layout_height="match_parent" 08 android:textAppearance="?android:attr/textAppearanceListItemSmall" 09 android:gravity="center_vertical" 10 android:paddingStart="?android:attr/listPreferredItemPaddingStart" 11 android:minHeight="?android:attr/listPreferredItemHeightSmall" 12 />

Main.java

01 packageccom.app.main; 02 03 importandroid.annotation.SuppressLint; 04 importandroid.app.ActionBar; 05 importandroid.app.Activity; 06 importandroid.app.FragmentTransaction; 07 importandroid.os.Bundle; 08 importandroid.widget.ArrayAdapter; 09 10 @SuppressLint("NewApi") 11 publicclassMainextendsActivityimplementsActionBar.OnNavigationListener { 12 13 ActionBar actionBar =null; 14 15 @Override 16 protectedvoidonCreate(Bundle savedInstanceState) { 17 super.onCreate(savedInstanceState); 18 setContentView(R.layout.main); 19 20 actionBar =this.getActionBar(); 21 22 actionBar.setDisplayShowTitleEnabled(true); 23 24 actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST); 25 26 actionBar.setListNavigationCallbacks(newArrayAdapter(Main.this, 27 R.layout.mytextview, R.id.text1,newString[] {"tab1","tab2", 28 "tab3"}),this); 29 30 } 31 32 @Override 33 publicbooleanonNavigationItemSelected(intitemPosition,longitemId) { 34 35 MyFragment mf =newMyFragment(); 36 Bundle bundle =newBundle(); 37 bundle.putInt("key", itemPosition +1); 38 mf.setArguments(bundle); 39 40 FragmentTransaction action =this.getFragmentManager() 41 .beginTransaction(); 42 action.replace(R.id.content, mf); 43 action.commit(); 44 returntrue; 45 } 46 47 }

实现的效果如图：