The file containing the source code shown below is located in the corresponding directory in <sdk>/samples/android-<version>/...
/* * Copyright (C) 2011 The Android开源工程 * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.supportv13.app; import java.util.ArrayList; import com.example.android.supportv13.R; import android.app.ActionBar; import android.app.ActionBar.Tab; import android.app.Activity; import android.app.Fragment; import android.app.FragmentTransaction; import android.content.Context; import android.os.Bundle; import android.support.v13.app.FragmentPagerAdapter; import android.support.v4.view.ViewPager; /** * This demonstrates the use of action bar tabs and how they interact * with other action bar features. */ public class ActionBarTabsPager extends Activity { ViewPager mViewPager; TabsAdapter mTabsAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mViewPager = new ViewPager(this); mViewPager.setId(R.id.pager); setContentView(mViewPager); final ActionBar bar = getActionBar(); bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS); bar.setDisplayOptions(0, ActionBar.DISPLAY_SHOW_TITLE); mTabsAdapter = new TabsAdapter(this, mViewPager); mTabsAdapter.addTab(bar.newTab().setText("Simple"), CountingFragment.class, null); mTabsAdapter.addTab(bar.newTab().setText("List"), FragmentPagerSupport.ArrayListFragment.class, null); mTabsAdapter.addTab(bar.newTab().setText("Cursor"), CursorFragment.class, null); if (savedInstanceState != null) { bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0)); } } @Override protected void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putInt("tab", getActionBar().getSelectedNavigationIndex()); } /** * This is a helper class that implements the management of tabs and all * details of connecting a ViewPager with associated TabHost. It relies on a * trick. Normally a tab host has a simple API for supplying a View or * Intent that each tab will show. This is not sufficient for switching * between pages. So instead we make the content part of the tab host * 0dp high (it is not shown) and the TabsAdapter supplies its own dummy * view to show as the tab content. It listens to changes in tabs, and takes * care of switch to the correct paged in the ViewPager whenever the selected * tab changes. */ public static class TabsAdapter extends FragmentPagerAdapter implements ActionBar.TabListener, ViewPager.OnPageChangeListener { private final Context mContext; private final ActionBar mActionBar; private final ViewPager mViewPager; private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>(); static final class TabInfo { private final Class<?> clss; private final Bundle args; TabInfo(Class<?> _class, Bundle _args) { clss = _class; args = _args; } } public TabsAdapter(Activity activity, ViewPager pager) { super(activity.getFragmentManager()); mContext = activity; mActionBar = activity.getActionBar(); mViewPager = pager; mViewPager.setAdapter(this); mViewPager.setOnPageChangeListener(this); } public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) { TabInfo info = new TabInfo(clss, args); tab.setTag(info); tab.setTabListener(this); mTabs.add(info); mActionBar.addTab(tab); notifyDataSetChanged(); } @Override public int getCount() { return mTabs.size(); } @Override public Fragment getItem(int position) { TabInfo info = mTabs.get(position); return Fragment.instantiate(mContext, info.clss.getName(), info.args); } @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageSelected(int position) { mActionBar.setSelectedNavigationItem(position); } @Override public void onPageScrollStateChanged(int state) { } @Override public void onTabSelected(Tab tab, FragmentTransaction ft) { Object tag = tab.getTag(); for (int i=0; i<mTabs.size(); i++) { if (mTabs.get(i) == tag) { mViewPager.setCurrentItem(i); } } } @Override public void onTabUnselected(Tab tab, FragmentTransaction ft) { } @Override public void onTabReselected(Tab tab, FragmentTransaction ft) { } } }