Question

我创建了一个FragmentActivity，用Eclipse显示带有Tabs的ActionBar。在第一个选项卡中，我显示带有列表的片段，并在下一个选项卡中显示带有文本的片段。然后我想要，当我选择第一个选项卡的一个项目时，更改另一个列表片段的第二个片段。这是我的代码：

Eclipse和我创建的TabActivity：

public class TabActivity extends FragmentActivity implements ActionBar.TabListener {

static final int NUM_TABS = MyTab.values().length;

public enum MyTab{
    Categorias(0), Productos(1);

    private final int index;

    MyTab(int i) {
        this.index = i;
    }
}


SectionsPagerAdapter mSectionsPagerAdapter;

ViewPager mViewPager;

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

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

    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 (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
        actionBar.addTab(actionBar.newTab()
                .setText(mSectionsPagerAdapter.getPageTitle(i))
                .setTabListener(this));
    }

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.pedido, menu);
    return true;
}

@Override
public void onTabSelected(ActionBar.Tab tab,
        FragmentTransaction fragmentTransaction) {
    mViewPager.setCurrentItem(position);
}

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

}

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

}

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

    private FragmentManager mFragmentManager;
    private TextoFragment mTextoFragment;

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

    @Override
    public Fragment getItem(int position) {
        return TabFragment.nuevoFragment(position);
    }

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

    @Override
    public CharSequence getPageTitle(int position) {
        Locale l = Locale.getDefault();
        switch (MyTab.values()[position]) {
        case Categorias:
            return getString(R.string.title_categorias).toUpperCase(l);
        case Productos:
            return getString(R.string.title_productos).toUpperCase(l);
        }
        return "";
    }
}

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

    static Fragment nuevoFragment(int position) {

        Fragment f;
        Bundle args = new Bundle();
        switch (Pestaña.values()[position]) {
        case Categorias:
            f = new ListaFragment();
            args.putInt("tipoObjeto", TipoObjeto.Categoria.ordinal());
            break;
        case Productos:
            if (EstadoHT.categoriaActual == null) {
                f = new TextoFragment();
                args.putString(TextoFragment.ARG_MENSAJE,
                        "Elija primero una categoría");
            } else {
                f = new ListaFragment();
                args.putInt(ListaFragment.ARG_TIPO_OBJETO,
                        TipoObjeto.Producto.ordinal());
            }
            break;
        default:
            f = new TabFragment();
            args = new Bundle();
            args.putInt(TabFragment.ARG_SECTION_NUMBER, position);
        }
        f.setArguments(args);
        return f;
    }

    private View lanzarEstadoPedido(LayoutInflater inflater,
            ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.tab_estado_pedido,
                container, false); // Muestra el layout

        TextView lblMesa = (TextView) rootView.findViewById(R.id.lblMesa);
        lblMesa.setText("Nada");
        return rootView;
    }

    public TabFragment() {

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        int valorPestaña = getArguments().getInt(ARG_SECTION_NUMBER, 0);
        switch (MyTab.values()[valorPestaña]) {

        case Pedido:
            return lanzarEstadoPedido(inflater, container,
                    savedInstanceState);

        default:
            return null;
        }
                  }

    }
}

在ListaFragment中：

public void onItemClick(AdapterView<?> arg0, View arg1,
                int position, long arg3) {
            Intent dato = new Intent();
            IObjetoHT o = (IObjetoHT) lvlista.getItemAtPosition(position);
            switch (tipo) {
            case Categoria:
                App.categoriaActual = (Categoria) o;
                TabActivity actPedido = (TabActivity) getActivity();
                ActionBar actionBar = actPedido.getActionBar();
                                              actPedido.mViewPager.setCurrentItem(TabActivity.MyTab.Productos.ordinal());

                break;
            case Producto:

                break;
            default:
                dato.putExtra(ARG_OBJETO_A_DEVOLVER, o);
                act.setResult(act.RESULT_OK, dato);
                act.finish();
            }

然后从ListaFragment我想上传第二个标签片段..是否可能？

Answer 1

您可以使用片段管理器跟踪正在添加到TabPagerAdapter的片段。

public class MainActivity extends FragmentActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TabAdapter = new TabPagerAdapter(getSupportFragmentManager(), context);
        Tab = (ViewPager)findViewById(R.id.pager);
        Tab.setOnPageChangeListener(
              new ViewPager.SimpleOnPageChangeListener() {
                   @Override
                   public void onPageSelected(int position) {
                        actionBar = getActionBar();
                        actionBar.setSelectedNavigationItem(position);
                        if(position == 1)
                        {
                            android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();

                            **MYACTIVITY fragment = (MYACTIVITY) fragmentManager.findFragmentByTag("YOUR TAG 1");**
                            fragment.get_recent();
                            Toast.makeText(context, "im visible", Toast.LENGTH_LONG).show();
                         }
                     }
              });

        Tab.setAdapter(TabAdapter);
        actionBar = getActionBar();
        //Enable Tabs on Action Bar
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        actionBar.addTab(actionBar.newTab().setText("TAB NAME 1").setTabListener(tabListener));
        actionBar.addTab(actionBar.newTab().setText("TAB NAME 2").setTabListener(tabListener));
        actionBar.addTab(actionBar.newTab().setText("TAB NAME 3").setTabListener(tabListener)); 


        android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager.beginTransaction().add(TabAdapter.getItem(0), "YOUR TAG 1").commit();
        fragmentManager.beginTransaction().add(TabAdapter.getItem(1), "YOUR TAG 2").commit();
        fragmentManager.beginTransaction().add(TabAdapter.getItem(2), "YOUR TAG 3").commit();
    }

public class TabPagerAdapter extends FragmentStatePagerAdapter {

    private Context context; 

    public TabPagerAdapter(FragmentManager fm, Context context) {
        super(fm);
        this.context = context;
        // TODO Auto-generated constructor stub
    }

    @Override
    public Fragment getItem(int i) {
        switch (i) {
        case 0:
            return new YOURACTIVITY1();
        case 1:
            return new YOURACTIVITY2();
        case 2:
             return new YOURACTIVITY3();
        }

        return null;
    }
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return 3; //No of Tabs
    }

}

如果您正在使用ActionBarSherlock，请小心，因为您需要明确声明使用android.support.v4.app.FragmentManager。

如何在viewpager选项卡中更新片段？

1 个答案: