在Android中，如何在一个选项卡中显示文本视图，而在其他选项卡中不显示？

Question

I want to be able to display a button and after that button is clicked for the string typed to appear in a listview. I have that done, but i dont want that to apply to every tab. I just want it to display the send button and text box in a certain tab. I did some research and found that I may have to create a different fragment class for every tab, but I dont know how I am suppose to do that.

Java Code

SectionsPagerAdapter mSectionsPagerAdapter;

/**
 * The {@link ViewPager} that will host the section contents.
 */
ViewPager mViewPager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    ListView list = (ListView)findViewById(R.id.messageList);
    adapter = new MyAdapter(this);
    list.setAdapter(adapter);
    // Set up the action bar.
    final ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

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

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    // When swiping between different sections, select the corresponding
    // tab. We can also use ActionBar.Tab#select() to do this if we have
    // a reference to the Tab.
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
        @Override
        public void onPageSelected(int position) {
            actionBar.setSelectedNavigationItem(position);
        }
    });

    // For each of the sections in the app, add a tab to the action bar.
    for (int i = 0; i < mSectionsPagerAdapter.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 callback (listener) for when
        // this tab is selected.
        actionBar.addTab(
                actionBar.newTab()
                        .setText(mSectionsPagerAdapter.getPageTitle(i))
                        .setTabListener(this));
    }
}






private void newGame() {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Developed by");
    builder.setMessage("Shirwa Mohamed @Team_Shirwa");
    builder.setPositiveButton( "ok", null);
    builder.create().show();

}

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

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

/**
 * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
 * one of the sections/tabs/pages.
 */
public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

    @Override
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page.
        // Return a DummySectionFragment (defined as a static inner class
        // below) with the page number as its lone argument.
        Fragment fragment = new DummySectionFragment();
        Bundle args = new Bundle();
        args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1);
        fragment.setArguments(args);
        return fragment;
    }



    @Override
    public CharSequence getPageTitle(int position) {
        Locale l = Locale.getDefault();
        switch (position) {
            case 0:
                return getString(R.string.title_section1).toUpperCase(l);
            case 1:
                return getString(R.string.title_section2).toUpperCase(l);
            case 2:
                return getString(R.string.title_section3).toUpperCase(l);
        }
        return null;
    }
}

/**
 * A dummy fragment representing a section of the app, but that simply
 * displays dummy text.
 */
public static class DummySectionFragment extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public DummySectionFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_main_dummy, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }
}

}

Activity XML :

    <TabHost
        android1:id="@android:id/tabhost"
        android1:layout_width="match_parent"
        android1:layout_height="match_parent"
        android1:layout_alignParentLeft="true"
        android1:layout_alignParentTop="true" >

        <LinearLayout
            android1:layout_width="match_parent"
            android1:layout_height="match_parent"
            android1:orientation="vertical" >

            <TabWidget
                android1:id="@android:id/tabs"
                android1:layout_width="match_parent"
                android1:layout_height="wrap_content" >
            </TabWidget>

            <FrameLayout
                android1:id="@android:id/tabcontent"
                android1:layout_width="match_parent"
                android1:layout_height="match_parent" >

                <LinearLayout
                    android1:id="@+id/tab1"
                    android1:layout_width="match_parent"
                    android1:layout_height="match_parent" >
                </LinearLayout>

                <LinearLayout
                    android1:id="@+id/tab2"
                    android1:layout_width="match_parent"
                    android1:layout_height="match_parent"
                     >

                </LinearLayout>

                <LinearLayout
                    android1:id="@+id/tab3"
                    android1:layout_width="match_parent"
                    android1:layout_height="match_parent" >
                </LinearLayout>
            </FrameLayout>
        </LinearLayout>
    </TabHost>

</RelativeLayout> 

Fragment Class?

    <TextView
        android:id="@+id/section_label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" 
        />

</RelativeLayout>

Answer 1

You are right, you need to create a fragment for each tab. Look at this link http://developer.android.com/guide/topics/ui/actionbar.html#Tabs it will help you understand how it works and how to implement it.