Java Android-在一个选项卡部分下有连接的活动

我正在研究下面的代码，但是我能够成功地编译它，我的问题是使用代码，我希望在一个选项卡部分中有一系列连接的活动。请给出你的建议和想法。整个消息来源于林克。非常感谢您的帮助和解释。谢谢

表1 -活动A->活动B->活动C

在这里：

MainActivity.java

public class MainActivity extends FragmentActivity implements ActionBar.TabListener {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide fragments for each of the
     * three primary sections of the app. We use a {@link android.support.v4.app.FragmentPagerAdapter}
     * derivative, which will keep every loaded fragment in memory. If this becomes too memory
     * intensive, it may be best to switch to a {@link android.support.v4.app.FragmentStatePagerAdapter}.
     */
    AppSectionsPagerAdapter mAppSectionsPagerAdapter;

    /**
     * The {@link ViewPager} that will display the three primary sections of the app, one at a
     * time.
     */
    ViewPager mViewPager;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Create the adapter that will return a fragment for each of the three primary sections
        // of the app.
        mAppSectionsPagerAdapter = new AppSectionsPagerAdapter(getSupportFragmentManager());

        // Set up the action bar.
        final ActionBar actionBar = getActionBar();

        // Specify that the Home/Up button should not be enabled, since there is no hierarchical
        // parent.
        actionBar.setHomeButtonEnabled(false);

        // Specify that we will be displaying tabs in the action bar.
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        // Set up the ViewPager, attaching the adapter and setting up a listener for when the
        // user swipes between sections.
        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mAppSectionsPagerAdapter);
        mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                // When swiping between different app sections, select the corresponding tab.
                // We can also use ActionBar.Tab#select() to do this if we have a reference to the
                // Tab.
                actionBar.setSelectedNavigationItem(position);
            }
        });

        // For each of the sections in the app, add a tab to the action bar.
        for (int i = 0; i < mAppSectionsPagerAdapter.getCount(); i++) {
            // Create a tab with text corresponding to the page title defined by the adapter.
            // Also specify this Activity object, which implements the TabListener interface, as the
            // listener for when this tab is selected.
            actionBar.addTab(
                    actionBar.newTab()
                            .setText(mAppSectionsPagerAdapter.getPageTitle(i))
                            .setTabListener(this));
        }
    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
        // When the given tab is selected, switch to the corresponding page in the ViewPager.
        mViewPager.setCurrentItem(tab.getPosition());
    }

    @Override
    public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to one of the primary
     * sections of the app.
     */
    public static class AppSectionsPagerAdapter extends FragmentPagerAdapter {

        public AppSectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int i) {
            switch (i) {
                case 0:
                    // The first section of the app is the most interesting -- it offers
                    // a launchpad into the other demonstrations in this example application.
                    return new LaunchpadSectionFragment();

                default:
                    // The other sections of the app are dummy placeholders.
                    Fragment fragment = new DummySectionFragment();
                    Bundle args = new Bundle();
                    args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, i + 1);
                    fragment.setArguments(args);
                    return fragment;
            }
        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return "Section " + (position + 1);
        }
    }

    /**
     * A fragment that launches other parts of the demo application.
     */
    public static class LaunchpadSectionFragment extends Fragment {

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_section_launchpad, container, false);

            // Demonstration of a collection-browsing activity.
            rootView.findViewById(R.id.demo_collection_button)
                    .setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View view) {
                            Intent intent = new Intent(getActivity(), CollectionDemoActivity.class);
                            startActivity(intent);
                        }
                    });

            // Demonstration of navigating to external activities.
            rootView.findViewById(R.id.demo_external_activity)
                    .setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View view) {
                            // Create an intent that asks the user to pick a photo, but using
                            // FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET, ensures that relaunching
                            // the application from the device home screen does not return
                            // to the external activity.
                            Intent externalActivityIntent = new Intent(Intent.ACTION_PICK);
                            externalActivityIntent.setType("image/*");
                            externalActivityIntent.addFlags(
                                    Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
                            startActivity(externalActivityIntent);
                        }
                    });

            return rootView;
        }
    }

    /**
     * A dummy fragment representing a section of the app, but that simply displays dummy text.
     */
    public static class DummySectionFragment extends Fragment {

        public static final String ARG_SECTION_NUMBER = "section_number";

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_section_dummy, container, false);
            Bundle args = getArguments();
            ((TextView) rootView.findViewById(android.R.id.text1)).setText(
                    getString(R.string.dummy_section_text, args.getInt(ARG_SECTION_NUMBER)));
            return rootView;
        }
    }
}

public class CollectionDemoActivity extends FragmentActivity {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide fragments representing
     * each object in a collection. We use a {@link android.support.v4.app.FragmentStatePagerAdapter}
     * derivative, which will destroy and re-create fragments as needed, saving and restoring their
     * state in the process. This is important to conserve memory and is a best practice when
     * allowing navigation between objects in a potentially large collection.
     */
    DemoCollectionPagerAdapter mDemoCollectionPagerAdapter;

    /**
     * The {@link android.support.v4.view.ViewPager} that will display the object collection.
     */
    ViewPager mViewPager;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_collection_demo);

        // Create an adapter that when requested, will return a fragment representing an object in
        // the collection.
        // 
        // ViewPager and its adapters use support library fragments, so we must use
        // getSupportFragmentManager.
        mDemoCollectionPagerAdapter = new DemoCollectionPagerAdapter(getSupportFragmentManager());

        // Set up action bar.
        final ActionBar actionBar = getActionBar();

        // Specify that the Home button should show an "Up" caret, indicating that touching the
        // button will take the user one step up in the application's hierarchy.
        actionBar.setDisplayHomeAsUpEnabled(true);

        // Set up the ViewPager, attaching the adapter.
        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mDemoCollectionPagerAdapter);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                // This is called when the Home (Up) button is pressed in the action bar.
                // Create a simple intent that starts the hierarchical parent activity and
                // use NavUtils in the Support Package to ensure proper handling of Up.
                Intent upIntent = new Intent(this, MainActivity.class);
                if (NavUtils.shouldUpRecreateTask(this, upIntent)) {
                    // This activity is not part of the application's task, so create a new task
                    // with a synthesized back stack.
                    TaskStackBuilder.from(this)
                            // If there are ancestor activities, they should be added here.
                            .addNextIntent(upIntent)
                            .startActivities();
                    finish();
                } else {
                    // This activity is part of the application's task, so simply
                    // navigate up to the hierarchical parent activity.
                    NavUtils.navigateUpTo(this, upIntent);
                }
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A {@link android.support.v4.app.FragmentStatePagerAdapter} that returns a fragment
     * representing an object in the collection.
     */
    public static class DemoCollectionPagerAdapter extends FragmentStatePagerAdapter {

        public DemoCollectionPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int i) {
            Fragment fragment = new DemoObjectFragment();
            Bundle args = new Bundle();
            args.putInt(DemoObjectFragment.ARG_OBJECT, i + 1); // Our object is just an integer :-P
            fragment.setArguments(args);
            return fragment;
        }

        @Override
        public int getCount() {
            // For this contrived example, we have a 100-object collection.
            return 100;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return "OBJECT " + (position + 1);
        }
    }

    /**
     * A dummy fragment representing a section of the app, but that simply displays dummy text.
     */
    public static class DemoObjectFragment extends Fragment {

        public static final String ARG_OBJECT = "object";

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_collection_object, container, false);
            Bundle args = getArguments();
            ((TextView) rootView.findViewById(android.R.id.text1)).setText(
                    Integer.toString(args.getInt(ARG_OBJECT)));
            return rootView;
        }
    }
}

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我了解到连接活动是不推荐的，只需使用嵌套片段即可

来自Docu：

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-片段像活动一样有自己的生命周期。

嗨！你们否决投票的理由应该有助于我编辑和构建更有效的问题。请提供信息反馈，以便我可以编辑我的问题。谢谢你，希望向你学习。