ActionBarSherlock, ViewPager, TabsAdapter nested Tab Fragments

问题

I implemented a ActionBarSherlock with a ViewPager and a TabsAdapter. It works well but now I tried to "push" from a Framework Loaded in "Tab 1" another Fragment.

The behavior should be like:

• I've 3 Tabs in my Application, When launching I see the first Tab where a Fragment with a Button is in it
• Pressing the Button on the First Tab, the Fragment on the First Tab should be replaced and another Fragment should be displayed

I tried to implement this, but I've a black Fragment when Replacing.

The Code:

FragmentDemoActivity.java

public class FragmentDemoActivity extends SherlockFragmentActivity {
    CustomViewPager  mViewPager;
    TabsAdapter mTabsAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        ActionBar bar = getSupportActionBar();
        bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        bar.setDisplayOptions(0, ActionBar.DISPLAY_SHOW_TITLE);

        mViewPager = (CustomViewPager)findViewById(R.id.pager);
        mViewPager.setSwipingEnabled(false);

        mTabsAdapter = new TabsAdapter(this, bar, mViewPager);
        mTabsAdapter.addTab(bar.newTab().setText("tab1"),
                FragmentA.class, null);
        mTabsAdapter.addTab(bar.newTab().setText("tab2"),
                FragmentB.class, null);

   setTitle(R.string.app_name);

        if (savedInstanceState != null) {
            bar.setSelectedNavigationItem(savedInstanceState.getInt("tab"));
        }
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putInt("tab", getSupportActionBar().getSelectedNavigationIndex());
    }

    public static class TabsAdapter extends FragmentPagerAdapter
            implements ViewPager.OnPageChangeListener, ActionBar.TabListener {
        private final Context mContext;
        private final ActionBar mBar;
        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(FragmentActivity activity, ActionBar bar, ViewPager pager) {
            super(activity.getSupportFragmentManager());
            mContext = activity;
            mBar = bar;
            mViewPager = pager;
            mViewPager.setAdapter(this);
            mViewPager.setOnPageChangeListener(this);
        }

        public void addTab(ActionBar.Tab tab, Class<? extends Fragment> clss, Bundle args) {
            TabInfo info = new TabInfo(clss, args);
            tab.setTag(info);
            tab.setTabListener(this);
            mTabs.add(info);
            mBar.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) {
            mBar.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,false);
                }
            }
        }

        @Override
        public void onTabUnselected(Tab tab, FragmentTransaction ft) {

        }

        @Override
        public void onTabReselected(Tab tab, FragmentTransaction ft) {

        }
    }

}

FragmentA.java

public class FragmentA extends Fragment {
    Button button;
    int num;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle saved)
    {
        return inflater.inflate(R.layout.frag_a, group, false);
    }

    @Override
    public void onActivityCreated (Bundle savedInstanceState)
    {
        super.onActivityCreated(savedInstanceState);
        num = 0;
        button = (Button) getActivity().findViewById(R.id.button1);
        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                FragmentB f1 = new FragmentB();
                FragmentTransaction ft = getActivity().getSupportFragmentManager().beginTransaction();
                ft.replace(R.id.pager, f1,"newTag");
                ft.show(f1);
                ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
                ft.addToBackStack(null);
                ft.commit();    

            }
        });
    }
}

I'm new at Android Development, so I'd be happy if someone is able to help me. I already investigated a lot of time to search a solution but the result wasn't as I expected.

My current project: http://cl.ly/3q1f2t1O2Y3j

回答1:

I gotcha!

Let me explain, you need to put an id on your Layout that you want to replace, my example:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/Framelay"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <TextView
        android:id="@+id/txtSearchTopic"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="10dp"
        android:text="TextView" />

</FrameLayout>

So I just put mine: android:id="@+id/Framelay" Then I can use this Id to replace for the new fragment, what I mean is that all the content inside this Layout will be replaced by the new Fragment, as I called DetailFragment.

FragmentManager fragmentManager = getFragmentManager();  
FragmentTransaction fragmentTransaction = fragmentManager  
        .beginTransaction();  
DetailFragment fragment3 = new DetailFragment();  
fragmentTransaction.replace(R.id.Framelay, fragment3);  
fragmentTransaction.commit(); 

来源：https://stackoverflow.com/questions/14389796/actionbarsherlock-viewpager-tabsadapter-nested-tab-fragments